[Geoserver-users] gs:Heatmap problems

Hi List,

I have been trying to use the new heatmap transformation in version 2.2.3 but I think I must be doing something wrong.

I wish to display a layer defined using an SQL view. The query simply returns a Grid of points and for each point there is a temperature value, I am using the round function in the query to round the temperature value to the nearest integer.

I am using the SLD below, copied from the example and modified to (hopefully) work with my data. However, the entire map is produced in one colour (#FFFF00) but when I query the map by clicking on it in an Openlayers preview it shows correct values for the Temperatures and different locations on the map yield different values.

Any ideas?

Heatmap

Heatmap

A heatmap showing upper air temperature

<ogc:Function name=“gs:Heatmap”>

<ogc:Function name=“parameter”>

ogc:Literaldata</ogc:Literal>

</ogc:Function>

<ogc:Function name=“parameter”>

ogc:LiteralweightAttr</ogc:Literal>

ogc:Literaltemperature</ogc:Literal>

</ogc:Function>

<ogc:Function name=“parameter”>

ogc:LiteralradiusPixels</ogc:Literal>

<ogc:Function name=“env”>

ogc:Literalradius</ogc:Literal>

ogc:Literal100</ogc:Literal>

</ogc:Function>

</ogc:Function>

<ogc:Function name=“parameter”>

ogc:LiteralpixelsPerCell</ogc:Literal>

ogc:Literal10</ogc:Literal>

</ogc:Function>

<ogc:Function name=“parameter”>

ogc:LiteraloutputBBOX</ogc:Literal>

<ogc:Function name=“env”>

ogc:Literalwms_bbox</ogc:Literal>

</ogc:Function>

</ogc:Function>

<ogc:Function name=“parameter”>

ogc:LiteraloutputWidth</ogc:Literal>

<ogc:Function name=“env”>

ogc:Literalwms_width</ogc:Literal>

</ogc:Function>

</ogc:Function>

<ogc:Function name=“parameter”>

ogc:LiteraloutputHeight</ogc:Literal>

<ogc:Function name=“env”>

ogc:Literalwms_height</ogc:Literal>

</ogc:Function>

</ogc:Function>

</ogc:Function>

ogc:PropertyNamelocation</ogc:PropertyName>

0.6

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and any attachments is strictly prohibited. If you have received this
communication in error, please notify us immediately by replying to this
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On Tue, Jan 8, 2013 at 3:03 PM, Chris Haste <CHaste@anonymised.com> wrote:

Hi List,

I have been trying to use the new heatmap transformation in version 2.2.3 but I think I must be doing something wrong.

I wish to display a layer defined using an SQL view. The query simply returns a Grid of points and for each point there is a temperature value, I am using the round function in the query to round the temperature value to the nearest integer.

I am using the SLD below, copied from the example and modified to (hopefully) work with my data. However, the entire map is produced in one colour (#FFFF00) but when I query the map by clicking on it in an Openlayers preview it shows correct values for the Temperatures and different locations on the map yield different values.

Any ideas?

Heatmaps are about point density, if you want to interpolation function you should look at the Barnes surface transformation
instead

Cheers
Andrea

==
Our support, Your Success! Visit http://opensdi.geo-solutions.it for more information.

Ing. Andrea Aime
@geowolf
Technical Lead

GeoSolutions S.A.S.
Via Poggio alle Viti 1187
55054 Massarosa (LU)
Italy
phone: +39 0584 962313
fax: +39 0584 1660272
mob: +39 339 8844549

http://www.geo-solutions.it
http://twitter.com/geosolutions_it


Hi Andrea,

I’m not sure I understand. Are you saying that I don’t have a sufficient number of points in my data? I have a regular grid of points covering the entire globe at 1.25 x 1.25 degree intervals. Is this not dense enough?

From: andrea.aime@anonymised.com [mailto:andrea.aime@anonymised.com] On Behalf Of Andrea Aime
Sent: 08 January 2013 14:09
To: Chris Haste
Cc: geoserver-users@lists.sourceforge.net
Subject: Re: [Geoserver-users] gs:Heatmap problems

On Tue, Jan 8, 2013 at 3:03 PM, Chris Haste <CHaste@anonymised.com> wrote:

Hi List,

I have been trying to use the new heatmap transformation in version 2.2.3 but I think I must be doing something wrong.

I wish to display a layer defined using an SQL view. The query simply returns a Grid of points and for each point there is a temperature value, I am using the round function in the query to round the temperature value to the nearest integer.

I am using the SLD below, copied from the example and modified to (hopefully) work with my data. However, the entire map is produced in one colour (#FFFF00) but when I query the map by clicking on it in an Openlayers preview it shows correct values for the Temperatures and different locations on the map yield different values.

Any ideas?

Heatmaps are about point density, if you want to interpolation function you should look at the Barnes surface transformation

instead

Cheers

Andrea

==

Our support, Your Success! Visit http://opensdi.geo-solutions.it for more information.

==

Ing. Andrea Aime

@geowolf

Technical Lead

GeoSolutions S.A.S.

Via Poggio alle Viti 1187

55054 Massarosa (LU)

Italy

phone: +39 0584 962313

fax: +39 0584 1660272

mob: +39 339 8844549

http://www.geo-solutions.it

http://twitter.com/geosolutions_it


*** This communication has been sent from World Fuel Services
Corporation or its subsidiaries or its affiliates for the intended recipient
only and may contain proprietary, confidential or privileged information.
If you are not the intended recipient, any review, disclosure, copying,
use, or distribution of the information included in this communication
and any attachments is strictly prohibited. If you have received this
communication in error, please notify us immediately by replying to this
communication and delete the communication, including any
attachments, from your computer. Electronic communications sent to or
from World Fuel Services Corporation or its subsidiaries or its affiliates
may be monitored for quality assurance and compliance purposes.***

On Tue, Jan 8, 2013 at 3:14 PM, Chris Haste <CHaste@anonymised.com> wrote:

Hi Andrea,

I’m not sure I understand. Are you saying that I don’t have a sufficient number of points in my data? I have a regular grid of points covering the entire globe at 1.25 x 1.25 degree intervals. Is this not dense enough?

I’m saying a heatmap shows a color based on the different concentration of points, not their value, so if the grid is regular it’s normal that
you get a solid color.

If you want to interpolate a value contained in the attributes of the points instead you have to use the Barnes surface instead.
See some docs here: http://suite.opengeo.org/docs/cartography/rt/barnes.html

Cheers
Andrea

From: andrea.aime@anonymised.com [mailto:andrea.aime@anonymised.com] On Behalf Of Andrea Aime
Sent: 08 January 2013 14:09
To: Chris Haste
Cc: geoserver-users@lists.sourceforge.net
Subject: Re: [Geoserver-users] gs:Heatmap problems

On Tue, Jan 8, 2013 at 3:03 PM, Chris Haste <CHaste@anonymised.com> wrote:

Hi List,

I have been trying to use the new heatmap transformation in version 2.2.3 but I think I must be doing something wrong.

I wish to display a layer defined using an SQL view. The query simply returns a Grid of points and for each point there is a temperature value, I am using the round function in the query to round the temperature value to the nearest integer.

I am using the SLD below, copied from the example and modified to (hopefully) work with my data. However, the entire map is produced in one colour (#FFFF00) but when I query the map by clicking on it in an Openlayers preview it shows correct values for the Temperatures and different locations on the map yield different values.

Any ideas?

Heatmaps are about point density, if you want to interpolation function you should look at the Barnes surface transformation

instead

Cheers

Andrea

==

Our support, Your Success! Visit http://opensdi.geo-solutions.it for more information.

==

Ing. Andrea Aime

@geowolf

Technical Lead

GeoSolutions S.A.S.

Via Poggio alle Viti 1187

55054 Massarosa (LU)

Italy

phone: +39 0584 962313

fax: +39 0584 1660272

mob: +39 339 8844549

http://www.geo-solutions.it

http://twitter.com/geosolutions_it


*** This communication has been sent from World Fuel Services

Corporation or its subsidiaries or its affiliates for the intended recipient
only and may contain proprietary, confidential or privileged information.
If you are not the intended recipient, any review, disclosure, copying,
use, or distribution of the information included in this communication
and any attachments is strictly prohibited. If you have received this
communication in error, please notify us immediately by replying to this
communication and delete the communication, including any
attachments, from your computer. Electronic communications sent to or
from World Fuel Services Corporation or its subsidiaries or its affiliates
may be monitored for quality assurance and compliance purposes.***

==
Our support, Your Success! Visit http://opensdi.geo-solutions.it for more information.

Ing. Andrea Aime
@geowolf
Technical Lead

GeoSolutions S.A.S.
Via Poggio alle Viti 1187
55054 Massarosa (LU)
Italy
phone: +39 0584 962313
fax: +39 0584 1660272
mob: +39 339 8844549

http://www.geo-solutions.it
http://twitter.com/geosolutions_it


Ah!

Thanks Andrea, I will go and try that one!

From: andrea.aime@anonymised.com [mailto:andrea.aime@anonymised.com] On Behalf Of Andrea Aime
Sent: 08 January 2013 14:18
To: Chris Haste
Cc: geoserver-users@anonymised.comsts.sourceforge.net
Subject: Re: [Geoserver-users] gs:Heatmap problems

On Tue, Jan 8, 2013 at 3:14 PM, Chris Haste <CHaste@anonymised.com> wrote:

Hi Andrea,

I’m not sure I understand. Are you saying that I don’t have a sufficient number of points in my data? I have a regular grid of points covering the entire globe at 1.25 x 1.25 degree intervals. Is this not dense enough?

I’m saying a heatmap shows a color based on the different concentration of points, not their value, so if the grid is regular it’s normal that

you get a solid color.

If you want to interpolate a value contained in the attributes of the points instead you have to use the Barnes surface instead.

See some docs here: http://suite.opengeo.org/docs/cartography/rt/barnes.html

Cheers

Andrea

From: andrea.aime@anonymised.com [mailto:andrea.aime@anonymised.com] On Behalf Of Andrea Aime
Sent: 08 January 2013 14:09
To: Chris Haste
Cc: geoserver-users@anonymised.comt
Subject: Re: [Geoserver-users] gs:Heatmap problems

On Tue, Jan 8, 2013 at 3:03 PM, Chris Haste <CHaste@anonymised.com> wrote:

Hi List,

I have been trying to use the new heatmap transformation in version 2.2.3 but I think I must be doing something wrong.

I wish to display a layer defined using an SQL view. The query simply returns a Grid of points and for each point there is a temperature value, I am using the round function in the query to round the temperature value to the nearest integer.

I am using the SLD below, copied from the example and modified to (hopefully) work with my data. However, the entire map is produced in one colour (#FFFF00) but when I query the map by clicking on it in an Openlayers preview it shows correct values for the Temperatures and different locations on the map yield different values.

Any ideas?

Heatmaps are about point density, if you want to interpolation function you should look at the Barnes surface transformation

instead

Cheers

Andrea

==

Our support, Your Success! Visit http://opensdi.geo-solutions.it for more information.

==

Ing. Andrea Aime

@geowolf

Technical Lead

GeoSolutions S.A.S.

Via Poggio alle Viti 1187

55054 Massarosa (LU)

Italy

phone: +39 0584 962313

fax: +39 0584 1660272

mob: +39 339 8844549

http://www.geo-solutions.it

http://twitter.com/geosolutions_it


*** This communication has been sent from World Fuel Services

Corporation or its subsidiaries or its affiliates for the intended recipient
only and may contain proprietary, confidential or privileged information.
If you are not the intended recipient, any review, disclosure, copying,
use, or distribution of the information included in this communication
and any attachments is strictly prohibited. If you have received this
communication in error, please notify us immediately by replying to this
communication and delete the communication, including any
attachments, from your computer. Electronic communications sent to or
from World Fuel Services Corporation or its subsidiaries or its affiliates
may be monitored for quality assurance and compliance purposes.***

==

Our support, Your Success! Visit http://opensdi.geo-solutions.it for more information.

==

Ing. Andrea Aime

@geowolf

Technical Lead

GeoSolutions S.A.S.

Via Poggio alle Viti 1187

55054 Massarosa (LU)

Italy

phone: +39 0584 962313

fax: +39 0584 1660272

mob: +39 339 8844549

http://www.geo-solutions.it

http://twitter.com/geosolutions_it


Well my initial attempts at this are resulting in nothing being displayed, so I’d like to check whether I have some of the basics correct.

I have an SQL View Layer called TemperatureMap. The SQL in this view returns a table of two columns: location of type Point and temperature of type Float.

I have set the appropriate (I think) parts of the SLD as follows:

TemperatureMap

<ogc:Function name=“gs:BarnesSurface”>
<ogc:Function name=“parameter”>
ogc:Literaldata</ogc:Literal>
</ogc:Function>

. . .

<ogc:Function name=“parameter”>
ogc:LiteralvalueAttr</ogc:Literal>
ogc:Literaltemperature</ogc:Literal>
</ogc:Function>

Is this correct?

From: Chris Haste [mailto:CHaste@anonymised.com]
Sent: 08 January 2013 14:20
To: Andrea Aime
Cc: geoserver-users@lists.sourceforge.net
Subject: Re: [Geoserver-users] gs:Heatmap problems

Ah!

Thanks Andrea, I will go and try that one!

From: andrea.aime@anonymised.com [mailto:andrea.aime@anonymised.com…84…] On Behalf Of Andrea Aime
Sent: 08 January 2013 14:18
To: Chris Haste
Cc: geoserver-users@anonymised.comge.net
Subject: Re: [Geoserver-users] gs:Heatmap problems

On Tue, Jan 8, 2013 at 3:14 PM, Chris Haste <CHaste@anonymised.com> wrote:

Hi Andrea,

I’m not sure I understand. Are you saying that I don’t have a sufficient number of points in my data? I have a regular grid of points covering the entire globe at 1.25 x 1.25 degree intervals. Is this not dense enough?

I’m saying a heatmap shows a color based on the different concentration of points, not their value, so if the grid is regular it’s normal that

you get a solid color.

If you want to interpolate a value contained in the attributes of the points instead you have to use the Barnes surface instead.

See some docs here: http://suite.opengeo.org/docs/cartography/rt/barnes.html

Cheers

Andrea

From: andrea.aime@anonymised.com [mailto:andrea.aime@anonymised.com] On Behalf Of Andrea Aime
Sent: 08 January 2013 14:09
To: Chris Haste
Cc: geoserver-users@lists.sourceforge.net
Subject: Re: [Geoserver-users] gs:Heatmap problems

On Tue, Jan 8, 2013 at 3:03 PM, Chris Haste <CHaste@anonymised.com> wrote:

Hi List,

I have been trying to use the new heatmap transformation in version 2.2.3 but I think I must be doing something wrong.

I wish to display a layer defined using an SQL view. The query simply returns a Grid of points and for each point there is a temperature value, I am using the round function in the query to round the temperature value to the nearest integer.

I am using the SLD below, copied from the example and modified to (hopefully) work with my data. However, the entire map is produced in one colour (#FFFF00) but when I query the map by clicking on it in an Openlayers preview it shows correct values for the Temperatures and different locations on the map yield different values.

Any ideas?

Heatmaps are about point density, if you want to interpolation function you should look at the Barnes surface transformation

instead

Cheers

Andrea

==

Our support, Your Success! Visit http://opensdi.geo-solutions.it for more information.

==

Ing. Andrea Aime

@geowolf

Technical Lead

GeoSolutions S.A.S.

Via Poggio alle Viti 1187

55054 Massarosa (LU)

Italy

phone: +39 0584 962313

fax: +39 0584 1660272

mob: +39 339 8844549

http://www.geo-solutions.it

http://twitter.com/geosolutions_it


*** This communication has been sent from World Fuel Services

Corporation or its subsidiaries or its affiliates for the intended recipient
only and may contain proprietary, confidential or privileged information.
If you are not the intended recipient, any review, disclosure, copying,
use, or distribution of the information included in this communication
and any attachments is strictly prohibited. If you have received this
communication in error, please notify us immediately by replying to this
communication and delete the communication, including any
attachments, from your computer. Electronic communications sent to or
from World Fuel Services Corporation or its subsidiaries or its affiliates
may be monitored for quality assurance and compliance purposes.***

==

Our support, Your Success! Visit http://opensdi.geo-solutions.it for more information.

==

Ing. Andrea Aime

@geowolf

Technical Lead

GeoSolutions S.A.S.

Via Poggio alle Viti 1187

55054 Massarosa (LU)

Italy

phone: +39 0584 962313

fax: +39 0584 1660272

mob: +39 339 8844549

http://www.geo-solutions.it

http://twitter.com/geosolutions_it


Another thing that may be a problem is the size of my dataset… Worldwide it consists of 41,760 points. Is this too large a number for the Transformation to handle?

From: Chris Haste
Sent: 08 January 2013 15:18
To: Chris Haste; Andrea Aime
Cc: geoserver-users@lists.sourceforge.net
Subject: RE: [Geoserver-users] gs:Heatmap problems

Well my initial attempts at this are resulting in nothing being displayed, so I’d like to check whether I have some of the basics correct.

I have an SQL View Layer called TemperatureMap. The SQL in this view returns a table of two columns: location of type Point and temperature of type Float.

I have set the appropriate (I think) parts of the SLD as follows:

TemperatureMap

<ogc:Function name=“gs:BarnesSurface”>
<ogc:Function name=“parameter”>
ogc:Literaldata</ogc:Literal>
</ogc:Function>

. . .

<ogc:Function name=“parameter”>
ogc:LiteralvalueAttr</ogc:Literal>
ogc:Literaltemperature</ogc:Literal>
</ogc:Function>

Is this correct?

From: Chris Haste [mailto:CHaste@anonymised.com992…]
Sent: 08 January 2013 14:20
To: Andrea Aime
Cc: geoserver-users@lists.sourceforge.net
Subject: Re: [Geoserver-users] gs:Heatmap problems

Ah!

Thanks Andrea, I will go and try that one!

From: andrea.aime@anonymised.com [mailto:andrea.aime@anonymised.com] On Behalf Of Andrea Aime
Sent: 08 January 2013 14:18
To: Chris Haste
Cc: geoserver-users@anonymised.coms.sourceforge.net
Subject: Re: [Geoserver-users] gs:Heatmap problems

On Tue, Jan 8, 2013 at 3:14 PM, Chris Haste <CHaste@anonymised.com> wrote:

Hi Andrea,

I’m not sure I understand. Are you saying that I don’t have a sufficient number of points in my data? I have a regular grid of points covering the entire globe at 1.25 x 1.25 degree intervals. Is this not dense enough?

I’m saying a heatmap shows a color based on the different concentration of points, not their value, so if the grid is regular it’s normal that

you get a solid color.

If you want to interpolate a value contained in the attributes of the points instead you have to use the Barnes surface instead.

See some docs here: http://suite.opengeo.org/docs/cartography/rt/barnes.html

Cheers

Andrea

From: andrea.aime@anonymised.com [mailto:andrea.aime@anonymised.com] On Behalf Of Andrea Aime
Sent: 08 January 2013 14:09
To: Chris Haste
Cc: geoserver-users@lists.sourceforge.net
Subject: Re: [Geoserver-users] gs:Heatmap problems

On Tue, Jan 8, 2013 at 3:03 PM, Chris Haste <CHaste@anonymised.com> wrote:

Hi List,

I have been trying to use the new heatmap transformation in version 2.2.3 but I think I must be doing something wrong.

I wish to display a layer defined using an SQL view. The query simply returns a Grid of points and for each point there is a temperature value, I am using the round function in the query to round the temperature value to the nearest integer.

I am using the SLD below, copied from the example and modified to (hopefully) work with my data. However, the entire map is produced in one colour (#FFFF00) but when I query the map by clicking on it in an Openlayers preview it shows correct values for the Temperatures and different locations on the map yield different values.

Any ideas?

Heatmaps are about point density, if you want to interpolation function you should look at the Barnes surface transformation

instead

Cheers

Andrea

==

Our support, Your Success! Visit http://opensdi.geo-solutions.it for more information.

==

Ing. Andrea Aime

@geowolf

Technical Lead

GeoSolutions S.A.S.

Via Poggio alle Viti 1187

55054 Massarosa (LU)

Italy

phone: +39 0584 962313

fax: +39 0584 1660272

mob: +39 339 8844549

http://www.geo-solutions.it

http://twitter.com/geosolutions_it


*** This communication has been sent from World Fuel Services

Corporation or its subsidiaries or its affiliates for the intended recipient
only and may contain proprietary, confidential or privileged information.
If you are not the intended recipient, any review, disclosure, copying,
use, or distribution of the information included in this communication
and any attachments is strictly prohibited. If you have received this
communication in error, please notify us immediately by replying to this
communication and delete the communication, including any
attachments, from your computer. Electronic communications sent to or
from World Fuel Services Corporation or its subsidiaries or its affiliates
may be monitored for quality assurance and compliance purposes.***

==

Our support, Your Success! Visit http://opensdi.geo-solutions.it for more information.

==

Ing. Andrea Aime

@geowolf

Technical Lead

GeoSolutions S.A.S.

Via Poggio alle Viti 1187

55054 Massarosa (LU)

Italy

phone: +39 0584 962313

fax: +39 0584 1660272

mob: +39 339 8844549

http://www.geo-solutions.it

http://twitter.com/geosolutions_it


Looks ok as far as it goes, but the other parameters are important as well.

41K points is probably pushing the bounds of BarnesSurface a bit too much. it’s really designed to interpolate relatively few scattered observations.

If you have a regular grid of observations there’s probably better and faster algorithms to use (although I’m not sure what would be the best choice.

On Tue, Jan 8, 2013 at 7:18 AM, Chris Haste <CHaste@anonymised.com> wrote:

Well my initial attempts at this are resulting in nothing being displayed, so I’d like to check whether I have some of the basics correct.

I have an SQL View Layer called TemperatureMap. The SQL in this view returns a table of two columns: location of type Point and temperature of type Float.

I have set the appropriate (I think) parts of the SLD as follows:

TemperatureMap

<ogc:Function name=“gs:BarnesSurface”>

<ogc:Function name=“parameter”>
ogc:Literaldata</ogc:Literal>
</ogc:Function>

. . .

<ogc:Function name=“parameter”>
ogc:LiteralvalueAttr</ogc:Literal>

ogc:Literaltemperature</ogc:Literal>
</ogc:Function>

Is this correct?

From: Chris Haste [mailto:CHaste@anonymised.com]
Sent: 08 January 2013 14:20
To: Andrea Aime

Cc: geoserver-users@lists.sourceforge.net
Subject: Re: [Geoserver-users] gs:Heatmap problems

Ah!

Thanks Andrea, I will go and try that one!

From: andrea.aime@anonymised.com [mailto:andrea.aime@anonymised.com] On Behalf Of Andrea Aime
Sent: 08 January 2013 14:18
To: Chris Haste
Cc: geoserver-users@lists.sourceforge.net
Subject: Re: [Geoserver-users] gs:Heatmap problems

On Tue, Jan 8, 2013 at 3:14 PM, Chris Haste <CHaste@anonymised.com> wrote:

Hi Andrea,

I’m not sure I understand. Are you saying that I don’t have a sufficient number of points in my data? I have a regular grid of points covering the entire globe at 1.25 x 1.25 degree intervals. Is this not dense enough?

I’m saying a heatmap shows a color based on the different concentration of points, not their value, so if the grid is regular it’s normal that

you get a solid color.

If you want to interpolate a value contained in the attributes of the points instead you have to use the Barnes surface instead.

See some docs here: http://suite.opengeo.org/docs/cartography/rt/barnes.html

Cheers

Andrea

From: andrea.aime@anonymised.com [mailto:andrea.aime@anonymised.com] On Behalf Of Andrea Aime
Sent: 08 January 2013 14:09
To: Chris Haste
Cc: geoserver-users@lists.sourceforge.net
Subject: Re: [Geoserver-users] gs:Heatmap problems

On Tue, Jan 8, 2013 at 3:03 PM, Chris Haste <CHaste@anonymised.com> wrote:

Hi List,

I have been trying to use the new heatmap transformation in version 2.2.3 but I think I must be doing something wrong.

I wish to display a layer defined using an SQL view. The query simply returns a Grid of points and for each point there is a temperature value, I am using the round function in the query to round the temperature value to the nearest integer.

I am using the SLD below, copied from the example and modified to (hopefully) work with my data. However, the entire map is produced in one colour (#FFFF00) but when I query the map by clicking on it in an Openlayers preview it shows correct values for the Temperatures and different locations on the map yield different values.

Any ideas?

Heatmaps are about point density, if you want to interpolation function you should look at the Barnes surface transformation

instead

Cheers

Andrea

==

Our support, Your Success! Visit http://opensdi.geo-solutions.it for more information.

==

Ing. Andrea Aime

@geowolf

Technical Lead

GeoSolutions S.A.S.

Via Poggio alle Viti 1187

55054 Massarosa (LU)

Italy

phone: +39 0584 962313

fax: +39 0584 1660272

mob: +39 339 8844549

http://www.geo-solutions.it

http://twitter.com/geosolutions_it


*** This communication has been sent from World Fuel Services

Corporation or its subsidiaries or its affiliates for the intended recipient
only and may contain proprietary, confidential or privileged information.
If you are not the intended recipient, any review, disclosure, copying,
use, or distribution of the information included in this communication
and any attachments is strictly prohibited. If you have received this
communication in error, please notify us immediately by replying to this
communication and delete the communication, including any
attachments, from your computer. Electronic communications sent to or
from World Fuel Services Corporation or its subsidiaries or its affiliates
may be monitored for quality assurance and compliance purposes.***

==

Our support, Your Success! Visit http://opensdi.geo-solutions.it for more information.

==

Ing. Andrea Aime

@geowolf

Technical Lead

GeoSolutions S.A.S.

Via Poggio alle Viti 1187

55054 Massarosa (LU)

Italy

phone: +39 0584 962313

fax: +39 0584 1660272

mob: +39 339 8844549

http://www.geo-solutions.it

http://twitter.com/geosolutions_it



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200+ hours of step-by-step video tutorials by Microsoft MVPs and experts.
SALE $99.99 this month only - learn more at:
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Geoserver-users mailing list
Geoserver-users@anonymised.comsts.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/geoserver-users

Martin Davis
OpenGeo - http://opengeo.org
Expert service straight from the developers.

+1 for everything Andrea said about Heatmaps - they are density maps, not interpolation surfaces.

Also, the output values are in the range [0,1], which is another reason you saw only one color in your output.

On Tue, Jan 8, 2013 at 6:17 AM, Andrea Aime <andrea.aime@anonymised.com> wrote:

On Tue, Jan 8, 2013 at 3:14 PM, Chris Haste <CHaste@anonymised.com992…> wrote:

Hi Andrea,

I’m not sure I understand. Are you saying that I don’t have a sufficient number of points in my data? I have a regular grid of points covering the entire globe at 1.25 x 1.25 degree intervals. Is this not dense enough?

I’m saying a heatmap shows a color based on the different concentration of points, not their value, so if the grid is regular it’s normal that
you get a solid color.

If you want to interpolate a value contained in the attributes of the points instead you have to use the Barnes surface instead.
See some docs here: http://suite.opengeo.org/docs/cartography/rt/barnes.html

Cheers

Andrea

From: andrea.aime@anonymised.com [mailto:andrea.aime@anonymised.com] On Behalf Of Andrea Aime
Sent: 08 January 2013 14:09
To: Chris Haste
Cc: geoserver-users@lists.sourceforge.net
Subject: Re: [Geoserver-users] gs:Heatmap problems

On Tue, Jan 8, 2013 at 3:03 PM, Chris Haste <CHaste@anonymised.com> wrote:

Hi List,

I have been trying to use the new heatmap transformation in version 2.2.3 but I think I must be doing something wrong.

I wish to display a layer defined using an SQL view. The query simply returns a Grid of points and for each point there is a temperature value, I am using the round function in the query to round the temperature value to the nearest integer.

I am using the SLD below, copied from the example and modified to (hopefully) work with my data. However, the entire map is produced in one colour (#FFFF00) but when I query the map by clicking on it in an Openlayers preview it shows correct values for the Temperatures and different locations on the map yield different values.

Any ideas?

Heatmaps are about point density, if you want to interpolation function you should look at the Barnes surface transformation

instead

Cheers

Andrea

==

Our support, Your Success! Visit http://opensdi.geo-solutions.it for more information.

==

Ing. Andrea Aime

@geowolf

Technical Lead

GeoSolutions S.A.S.

Via Poggio alle Viti 1187

55054 Massarosa (LU)

Italy

phone: +39 0584 962313

fax: +39 0584 1660272

mob: +39 339 8844549

http://www.geo-solutions.it

http://twitter.com/geosolutions_it


*** This communication has been sent from World Fuel Services

Corporation or its subsidiaries or its affiliates for the intended recipient
only and may contain proprietary, confidential or privileged information.
If you are not the intended recipient, any review, disclosure, copying,
use, or distribution of the information included in this communication
and any attachments is strictly prohibited. If you have received this
communication in error, please notify us immediately by replying to this
communication and delete the communication, including any
attachments, from your computer. Electronic communications sent to or
from World Fuel Services Corporation or its subsidiaries or its affiliates
may be monitored for quality assurance and compliance purposes.***

==
Our support, Your Success! Visit http://opensdi.geo-solutions.it for more information.

Ing. Andrea Aime
@geowolf
Technical Lead

GeoSolutions S.A.S.
Via Poggio alle Viti 1187
55054 Massarosa (LU)
Italy
phone: +39 0584 962313
fax: +39 0584 1660272
mob: +39 339 8844549

http://www.geo-solutions.it
http://twitter.com/geosolutions_it



Master SQL Server Development, Administration, T-SQL, SSAS, SSIS, SSRS
and more. Get SQL Server skills now (including 2012) with LearnDevNow -
200+ hours of step-by-step video tutorials by Microsoft MVPs and experts.
SALE $99.99 this month only - learn more at:
http://p.sf.net/sfu/learnmore_122512


Geoserver-users mailing list
Geoserver-users@anonymised.comsts.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/geoserver-users

Martin Davis
OpenGeo - http://opengeo.org
Expert service straight from the developers.

Thanks for the input Martin.

I can understand that 41K points may be an issue but even when I request a much smaller bounding box in order to significantly reduce the number of points being used I still don’t get anything displayed.

The data is a regular grid of points with a 1.25 x 1.25 degree spacing. The CRS is EPSG:4326. Would you be able to suggest suitable values for the other parameters, namely:

Scale, convergence, minObservations, maxObservationDistance (not sure if this should be meters or degrees), pixelsPerCell and queryBuffer?

From: Martin Davis [mailto:mdavis@anonymised.com]
Sent: 08 January 2013 17:28
To: Chris Haste
Cc: Andrea Aime; geoserver-users@lists.sourceforge.net
Subject: Re: [Geoserver-users] gs:Heatmap problems

Looks ok as far as it goes, but the other parameters are important as well.

41K points is probably pushing the bounds of BarnesSurface a bit too much. it’s really designed to interpolate relatively few scattered observations.

If you have a regular grid of observations there’s probably better and faster algorithms to use (although I’m not sure what would be the best choice.

On Tue, Jan 8, 2013 at 7:18 AM, Chris Haste <CHaste@anonymised.com> wrote:

Well my initial attempts at this are resulting in nothing being displayed, so I’d like to check whether I have some of the basics correct.

I have an SQL View Layer called TemperatureMap. The SQL in this view returns a table of two columns: location of type Point and temperature of type Float.

I have set the appropriate (I think) parts of the SLD as follows:

TemperatureMap

<ogc:Function name=“gs:BarnesSurface”>

<ogc:Function name=“parameter”>
ogc:Literaldata</ogc:Literal>
</ogc:Function>

. . .

<ogc:Function name=“parameter”>
ogc:LiteralvalueAttr</ogc:Literal>

ogc:Literaltemperature</ogc:Literal>
</ogc:Function>

Is this correct?

From: Chris Haste [mailto:CHaste@anonymised.com]
Sent: 08 January 2013 14:20
To: Andrea Aime

Cc: geoserver-users@lists.sourceforge.net
Subject: Re: [Geoserver-users] gs:Heatmap problems

Ah!

Thanks Andrea, I will go and try that one!

From: andrea.aime@anonymised.com [mailto:andrea.aime@anonymised.com] On Behalf Of Andrea Aime
Sent: 08 January 2013 14:18
To: Chris Haste
Cc: geoserver-users@lists.sourceforge.net
Subject: Re: [Geoserver-users] gs:Heatmap problems

On Tue, Jan 8, 2013 at 3:14 PM, Chris Haste <CHaste@anonymised.com> wrote:

Hi Andrea,

I’m not sure I understand. Are you saying that I don’t have a sufficient number of points in my data? I have a regular grid of points covering the entire globe at 1.25 x 1.25 degree intervals. Is this not dense enough?

I’m saying a heatmap shows a color based on the different concentration of points, not their value, so if the grid is regular it’s normal that

you get a solid color.

If you want to interpolate a value contained in the attributes of the points instead you have to use the Barnes surface instead.

See some docs here: http://suite.opengeo.org/docs/cartography/rt/barnes.html

Cheers

Andrea

From: andrea.aime@anonymised.com [mailto:andrea.aime@anonymised.com] On Behalf Of Andrea Aime
Sent: 08 January 2013 14:09
To: Chris Haste
Cc: geoserver-users@lists.sourceforge.net
Subject: Re: [Geoserver-users] gs:Heatmap problems

On Tue, Jan 8, 2013 at 3:03 PM, Chris Haste <CHaste@anonymised.com> wrote:

Hi List,

I have been trying to use the new heatmap transformation in version 2.2.3 but I think I must be doing something wrong.

I wish to display a layer defined using an SQL view. The query simply returns a Grid of points and for each point there is a temperature value, I am using the round function in the query to round the temperature value to the nearest integer.

I am using the SLD below, copied from the example and modified to (hopefully) work with my data. However, the entire map is produced in one colour (#FFFF00) but when I query the map by clicking on it in an Openlayers preview it shows correct values for the Temperatures and different locations on the map yield different values.

Any ideas?

Heatmaps are about point density, if you want to interpolation function you should look at the Barnes surface transformation

instead

Cheers

Andrea

==

Our support, Your Success! Visit http://opensdi.geo-solutions.it for more information.

==

Ing. Andrea Aime

@geowolf

Technical Lead

GeoSolutions S.A.S.

Via Poggio alle Viti 1187

55054 Massarosa (LU)

Italy

phone: +39 0584 962313

fax: +39 0584 1660272

mob: +39 339 8844549

http://www.geo-solutions.it

http://twitter.com/geosolutions_it


*** This communication has been sent from World Fuel Services

Corporation or its subsidiaries or its affiliates for the intended recipient
only and may contain proprietary, confidential or privileged information.
If you are not the intended recipient, any review, disclosure, copying,
use, or distribution of the information included in this communication
and any attachments is strictly prohibited. If you have received this
communication in error, please notify us immediately by replying to this
communication and delete the communication, including any
attachments, from your computer. Electronic communications sent to or
from World Fuel Services Corporation or its subsidiaries or its affiliates
may be monitored for quality assurance and compliance purposes.***

==

Our support, Your Success! Visit http://opensdi.geo-solutions.it for more information.

==

Ing. Andrea Aime

@geowolf

Technical Lead

GeoSolutions S.A.S.

Via Poggio alle Viti 1187

55054 Massarosa (LU)

Italy

phone: +39 0584 962313

fax: +39 0584 1660272

mob: +39 339 8844549

http://www.geo-solutions.it

http://twitter.com/geosolutions_it



Master SQL Server Development, Administration, T-SQL, SSAS, SSIS, SSRS
and more. Get SQL Server skills now (including 2012) with LearnDevNow -
200+ hours of step-by-step video tutorials by Microsoft MVPs and experts.
SALE $99.99 this month only - learn more at:
http://p.sf.net/sfu/learnmore_122512


Geoserver-users mailing list
Geoserver-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/geoserver-users

Martin Davis

OpenGeo - http://opengeo.org

Expert service straight from the developers.

To try and confirm if things are working you might try something like:

Scale = 3
Convergence = default
minObservations = default
maxObservationDistance = 0 (default) - at least initially to try and get something to show up. This is in units of the source CRS
pixelsPerCell = 4 (bigger number means faster computation)
queryBuffer = 0 (default; for test purposes, probably want to increase this in final design)

Also, for testing it’s best to view the output in the input CRS. There were some issues with reprojecting the output of RTs which were fixed recently (not sure what GS version you are using).

If you can create a layer with a small subset of your data that would be good too. Even better, post it and your SLD so that others can try and reproduce the problem.

Finally, it’s possible there is some bug that is preventing the result from being computed correctly. Stepping through in the debugger is the only way to check this.

On Tue, Jan 8, 2013 at 9:48 AM, Chris Haste <CHaste@anonymised.com> wrote:

Thanks for the input Martin.

I can understand that 41K points may be an issue but even when I request a much smaller bounding box in order to significantly reduce the number of points being used I still don’t get anything displayed.

The data is a regular grid of points with a 1.25 x 1.25 degree spacing. The CRS is EPSG:4326. Would you be able to suggest suitable values for the other parameters, namely:

Scale, convergence, minObservations, maxObservationDistance (not sure if this should be meters or degrees), pixelsPerCell and queryBuffer?

From: Martin Davis [mailto:mdavis@anonymised.com]
Sent: 08 January 2013 17:28
To: Chris Haste
Cc: Andrea Aime; geoserver-users@lists.sourceforge.net

Subject: Re: [Geoserver-users] gs:Heatmap problems

Looks ok as far as it goes, but the other parameters are important as well.

41K points is probably pushing the bounds of BarnesSurface a bit too much. it’s really designed to interpolate relatively few scattered observations.

If you have a regular grid of observations there’s probably better and faster algorithms to use (although I’m not sure what would be the best choice.

On Tue, Jan 8, 2013 at 7:18 AM, Chris Haste <CHaste@anonymised.com> wrote:

Well my initial attempts at this are resulting in nothing being displayed, so I’d like to check whether I have some of the basics correct.

I have an SQL View Layer called TemperatureMap. The SQL in this view returns a table of two columns: location of type Point and temperature of type Float.

I have set the appropriate (I think) parts of the SLD as follows:

TemperatureMap

<ogc:Function name=“gs:BarnesSurface”>

<ogc:Function name=“parameter”>
ogc:Literaldata</ogc:Literal>
</ogc:Function>

. . .

<ogc:Function name=“parameter”>
ogc:LiteralvalueAttr</ogc:Literal>

ogc:Literaltemperature</ogc:Literal>
</ogc:Function>

Is this correct?

From: Chris Haste [mailto:CHaste@anonymised.com]
Sent: 08 January 2013 14:20
To: Andrea Aime

Cc: geoserver-users@anonymised.comists.sourceforge.net
Subject: Re: [Geoserver-users] gs:Heatmap problems

Ah!

Thanks Andrea, I will go and try that one!

From: andrea.aime@anonymised.com [mailto:andrea.aime@anonymised.com] On Behalf Of Andrea Aime
Sent: 08 January 2013 14:18
To: Chris Haste
Cc: geoserver-users@lists.sourceforge.net
Subject: Re: [Geoserver-users] gs:Heatmap problems

On Tue, Jan 8, 2013 at 3:14 PM, Chris Haste <CHaste@anonymised.com> wrote:

Hi Andrea,

I’m not sure I understand. Are you saying that I don’t have a sufficient number of points in my data? I have a regular grid of points covering the entire globe at 1.25 x 1.25 degree intervals. Is this not dense enough?

I’m saying a heatmap shows a color based on the different concentration of points, not their value, so if the grid is regular it’s normal that

you get a solid color.

If you want to interpolate a value contained in the attributes of the points instead you have to use the Barnes surface instead.

See some docs here: http://suite.opengeo.org/docs/cartography/rt/barnes.html

Cheers

Andrea

From: andrea.aime@anonymised.com [mailto:andrea.aime@anonymised.com] On Behalf Of Andrea Aime
Sent: 08 January 2013 14:09
To: Chris Haste
Cc: geoserver-users@lists.sourceforge.net
Subject: Re: [Geoserver-users] gs:Heatmap problems

On Tue, Jan 8, 2013 at 3:03 PM, Chris Haste <CHaste@anonymised.com> wrote:

Hi List,

I have been trying to use the new heatmap transformation in version 2.2.3 but I think I must be doing something wrong.

I wish to display a layer defined using an SQL view. The query simply returns a Grid of points and for each point there is a temperature value, I am using the round function in the query to round the temperature value to the nearest integer.

I am using the SLD below, copied from the example and modified to (hopefully) work with my data. However, the entire map is produced in one colour (#FFFF00) but when I query the map by clicking on it in an Openlayers preview it shows correct values for the Temperatures and different locations on the map yield different values.

Any ideas?

Heatmaps are about point density, if you want to interpolation function you should look at the Barnes surface transformation

instead

Cheers

Andrea

==

Our support, Your Success! Visit http://opensdi.geo-solutions.it for more information.

==

Ing. Andrea Aime

@geowolf

Technical Lead

GeoSolutions S.A.S.

Via Poggio alle Viti 1187

55054 Massarosa (LU)

Italy

phone: +39 0584 962313

fax: +39 0584 1660272

mob: +39 339 8844549

http://www.geo-solutions.it

http://twitter.com/geosolutions_it


*** This communication has been sent from World Fuel Services

Corporation or its subsidiaries or its affiliates for the intended recipient
only and may contain proprietary, confidential or privileged information.
If you are not the intended recipient, any review, disclosure, copying,
use, or distribution of the information included in this communication
and any attachments is strictly prohibited. If you have received this
communication in error, please notify us immediately by replying to this
communication and delete the communication, including any
attachments, from your computer. Electronic communications sent to or
from World Fuel Services Corporation or its subsidiaries or its affiliates
may be monitored for quality assurance and compliance purposes.***

==

Our support, Your Success! Visit http://opensdi.geo-solutions.it for more information.

==

Ing. Andrea Aime

@geowolf

Technical Lead

GeoSolutions S.A.S.

Via Poggio alle Viti 1187

55054 Massarosa (LU)

Italy

phone: +39 0584 962313

fax: +39 0584 1660272

mob: +39 339 8844549

http://www.geo-solutions.it

http://twitter.com/geosolutions_it



Master SQL Server Development, Administration, T-SQL, SSAS, SSIS, SSRS
and more. Get SQL Server skills now (including 2012) with LearnDevNow -
200+ hours of step-by-step video tutorials by Microsoft MVPs and experts.
SALE $99.99 this month only - learn more at:
http://p.sf.net/sfu/learnmore_122512


Geoserver-users mailing list
Geoserver-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/geoserver-users

Martin Davis

OpenGeo - http://opengeo.org

Expert service straight from the developers.

Martin Davis
OpenGeo - http://opengeo.org
Expert service straight from the developers.

Hi,

There are also use cases for density maps weighted by a value of some attribute like sum of dollars lost in traffic accidents. Barnes surfaces does not suit for this, nor unweighted density maps. I have been creating such visualisations with SAGA GIS and Sextante which both have functions for this but the result is a static image that does not suit well for a web map with large scale range.
Discussion about this and one nice image in http://gis.stackexchange.com/questions/39074/whats-the-best-way-to-produce-a-density-map-from-weighted-points-in-qgis

It would be nice to be able to do something similar dynamically with Geoserver.

-Jukka Rahkonen-

________________________________
Martin Davis wrote:

+1 for everything Andrea said about Heatmaps - they are density maps, not interpolation surfaces.

Also, the output values are in the range [0,1], which is another reason you saw only one color in your output.

On Tue, Jan 8, 2013 at 6:17 AM, Andrea Aime <andrea.aime@anonymised.com<mailto:andrea.aime@anonymised.com>> wrote:
On Tue, Jan 8, 2013 at 3:14 PM, Chris Haste <CHaste@anonymised.com<mailto:CHaste@anonymised.com>> wrote:
Hi Andrea,

I’m not sure I understand. Are you saying that I don’t have a sufficient number of points in my data? I have a regular grid of points covering the entire globe at 1.25 x 1.25 degree intervals. Is this not dense enough?

I'm saying a heatmap shows a color based on the different concentration of points, not their value, so if the grid is regular it's normal that
you get a solid color.

If you want to interpolate a value contained in the attributes of the points instead you have to use the Barnes surface instead.
See some docs here: http://suite.opengeo.org/docs/cartography/rt/barnes.html

Cheers
Andrea

From: andrea.aime@anonymised.com<mailto:andrea.aime@anonymised.com> [mailto:andrea.aime@anonymised.com] On Behalf Of Andrea Aime
Sent: 08 January 2013 14:09
To: Chris Haste
Cc: geoserver-users@lists.sourceforge.net<mailto:geoserver-users@anonymised.comceforge.net>
Subject: Re: [Geoserver-users] gs:Heatmap problems

On Tue, Jan 8, 2013 at 3:03 PM, Chris Haste <CHaste@anonymised.com<mailto:CHaste@anonymised.com>> wrote:
Hi List,

I have been trying to use the new heatmap transformation in version 2.2.3 but I think I must be doing something wrong.
I wish to display a layer defined using an SQL view. The query simply returns a Grid of points and for each point there is a temperature value, I am using the round function in the query to round the temperature value to the nearest integer.

I am using the SLD below, copied from the example and modified to (hopefully) work with my data. However, the entire map is produced in one colour (#FFFF00) but when I query the map by clicking on it in an Openlayers preview it shows correct values for the Temperatures and different locations on the map yield different values.

Any ideas?

Heatmaps are about point density, if you want to interpolation function you should look at the Barnes surface transformation
instead

Cheers
Andrea

--

Our support, Your Success! Visit http://opensdi.geo-solutions.it for more information.

Ing. Andrea Aime
@geowolf
Technical Lead

GeoSolutions S.A.S.
Via Poggio alle Viti 1187
55054 Massarosa (LU)
Italy
phone: +39 0584 962313<tel:%2B39%200584%20962313>
fax: +39 0584 1660272<tel:%2B39%200584%201660272>
mob: +39 339 8844549<tel:%2B39%20%C2%A0339%208844549>

http://www.geo-solutions.it
http://twitter.com/geosolutions_it

-------------------------------------------------------

*** This communication has been sent from World Fuel Services

Corporation or its subsidiaries or its affiliates for the intended recipient
only and may contain proprietary, confidential or privileged information.
If you are not the intended recipient, any review, disclosure, copying,
use, or distribution of the information included in this communication
and any attachments is strictly prohibited. If you have received this
communication in error, please notify us immediately by replying to this
communication and delete the communication, including any
attachments, from your computer. Electronic communications sent to or
from World Fuel Services Corporation or its subsidiaries or its affiliates
may be monitored for quality assurance and compliance purposes.***

--

Our support, Your Success! Visit http://opensdi.geo-solutions.it for more information.

Ing. Andrea Aime
@geowolf
Technical Lead

GeoSolutions S.A.S.
Via Poggio alle Viti 1187
55054 Massarosa (LU)
Italy
phone: +39 0584 962313<tel:%2B39%200584%20962313>
fax: +39 0584 1660272<tel:%2B39%200584%201660272>
mob: +39 339 8844549<tel:%2B39%20%C2%A0339%208844549>

http://www.geo-solutions.it
http://twitter.com/geosolutions_it

-------------------------------------------------------

------------------------------------------------------------------------------
Master SQL Server Development, Administration, T-SQL, SSAS, SSIS, SSRS
and more. Get SQL Server skills now (including 2012) with LearnDevNow -
200+ hours of step-by-step video tutorials by Microsoft MVPs and experts.
SALE $99.99 this month only - learn more at:
http://p.sf.net/sfu/learnmore_122512
_______________________________________________
Geoserver-users mailing list
Geoserver-users@lists.sourceforge.net<mailto:Geoserver-users@anonymised.comrge.net>
https://lists.sourceforge.net/lists/listinfo/geoserver-users

--
Martin Davis
OpenGeo - http://opengeo.org/&gt;
Expert service straight from the developers.

Actually the Heatmap process does allow specifying an attribute of the input geometries to be used as a weighting attribute (parameter “weightAttr” - see http://suite.opengeo.org/opengeo-docs/cartography/rt/heatmap.html). So maybe you have what you need already!

This still doesn’t address the original problem, because:

  • the output range of the Heatmap is in [0,1], rather than the units of the input attribute (and there’s no obvious way of correlating the two, AFAIK)
  • since Heatmap is a density surface, the maximum value at any single point is less than the original input value at that point. Barnes surface also does a certain amount of averaging, but the effect is much less.

There’s a good explanation by whuber of the difference between heatmaps and interpolation surfaces in one of the comments of the gis.stackexchange post. Incidentally, after reading whuber’s complaint about the misuse of the term “Heatmap” I sort of wish I’d called the process KernelDensity instead…

M

On Tue, Jan 8, 2013 at 1:44 PM, Rahkonen Jukka <Jukka.Rahkonen@anonymised.com> wrote:

Hi,

There are also use cases for density maps weighted by a value of some attribute like sum of dollars lost in traffic accidents. Barnes surfaces does not suit for this, nor unweighted density maps. I have been creating such visualisations with SAGA GIS and Sextante which both have functions for this but the result is a static image that does not suit well for a web map with large scale range.
Discussion about this and one nice image in http://gis.stackexchange.com/questions/39074/whats-the-best-way-to-produce-a-density-map-from-weighted-points-in-qgis

It would be nice to be able to do something similar dynamically with Geoserver.

-Jukka Rahkonen-


Martin Davis wrote:

+1 for everything Andrea said about Heatmaps - they are density maps, not interpolation surfaces.

Also, the output values are in the range [0,1], which is another reason you saw only one color in your output.

On Tue, Jan 8, 2013 at 6:17 AM, Andrea Aime <andrea.aime@anonymised.commailto:[andrea.aime@anonymised.com](mailto:andrea.aime@anonymised.com)> wrote:
On Tue, Jan 8, 2013 at 3:14 PM, Chris Haste <CHaste@anonymised.commailto:[CHaste@anonymised.com](mailto:CHaste@anonymised.com..)> wrote:
Hi Andrea,

I’m not sure I understand. Are you saying that I don’t have a sufficient number of points in my data? I have a regular grid of points covering the entire globe at 1.25 x 1.25 degree intervals. Is this not dense enough?

I’m saying a heatmap shows a color based on the different concentration of points, not their value, so if the grid is regular it’s normal that
you get a solid color.

If you want to interpolate a value contained in the attributes of the points instead you have to use the Barnes surface instead.
See some docs here: http://suite.opengeo.org/docs/cartography/rt/barnes.html

Cheers
Andrea

From: andrea.aime@anonymised.commailto:[andrea.aime@anonymised.com](mailto:andrea.aime@anonymised.com) [mailto:andrea.aime@anonymised.commailto:[andrea.aime@anonymised.com](mailto:andrea.aime@anonymised.com)] On Behalf Of Andrea Aime

Sent: 08 January 2013 14:09
To: Chris Haste

Cc: geoserver-users@lists.sourceforge.netmailto:[geoserver-users@lists.sourceforge.net](mailto:geoserver-users@lists.sourceforge.net)

Subject: Re: [Geoserver-users] gs:Heatmap problems

On Tue, Jan 8, 2013 at 3:03 PM, Chris Haste <CHaste@anonymised.commailto:[CHaste@anonymised.com](mailto:CHaste@anonymised.com)> wrote:
Hi List,

I have been trying to use the new heatmap transformation in version 2.2.3 but I think I must be doing something wrong.
I wish to display a layer defined using an SQL view. The query simply returns a Grid of points and for each point there is a temperature value, I am using the round function in the query to round the temperature value to the nearest integer.

I am using the SLD below, copied from the example and modified to (hopefully) work with my data. However, the entire map is produced in one colour (#FFFF00) but when I query the map by clicking on it in an Openlayers preview it shows correct values for the Temperatures and different locations on the map yield different values.

Any ideas?

Heatmaps are about point density, if you want to interpolation function you should look at the Barnes surface transformation
instead

Cheers
Andrea

Our support, Your Success! Visit http://opensdi.geo-solutions.it for more information.

Ing. Andrea Aime
@geowolf
Technical Lead

GeoSolutions S.A.S.
Via Poggio alle Viti 1187
55054 Massarosa (LU)
Italy

phone: +39 0584 962313tel:%2B39%200584%20962313
fax: +39 0584 1660272tel:%2B39%200584%201660272
mob: +39 339 8844549tel:%2B39%20 339%208844549

http://www.geo-solutions.it
http://twitter.com/geosolutions_it


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Our support, Your Success! Visit http://opensdi.geo-solutions.it for more information.

Ing. Andrea Aime
@geowolf
Technical Lead

GeoSolutions S.A.S.
Via Poggio alle Viti 1187
55054 Massarosa (LU)
Italy

phone: +39 0584 962313tel:%2B39%200584%20962313
fax: +39 0584 1660272tel:%2B39%200584%201660272
mob: +39 339 8844549tel:%2B39%20 339%208844549

http://www.geo-solutions.it
http://twitter.com/geosolutions_it



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and more. Get SQL Server skills now (including 2012) with LearnDevNow -
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Martin Davis

OpenGeo - http://opengeo.org<http://opengeo.org/>

Expert service straight from the developers.


Master SQL Server Development, Administration, T-SQL, SSAS, SSIS, SSRS
and more. Get SQL Server skills now (including 2012) with LearnDevNow -
200+ hours of step-by-step video tutorials by Microsoft MVPs and experts.
SALE $99.99 this month only - learn more at:
http://p.sf.net/sfu/learnmore_122512


Geoserver-users mailing list
Geoserver-users@anonymised.comsts.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/geoserver-users

Martin Davis
OpenGeo - http://opengeo.org
Expert service straight from the developers.