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On 8/27/12 11:24 AM, klo uo wrote:
> On Mon, Aug 27, 2012 at 2:34 PM, Jeff Whitaker wrote:
>> Klo:  WMS servers use EPSG codes to define map projections - Basemap uses a
>> set of kwargs.  We need some way of inferring epsg codes from the Basemap
>> kwargs.  Alternatively, we could extend Basemap so it can accept EPSG codes.
>> But, there are many EPSG codes that don't correspond to allowable Basemap
>> projections, and valid Basemap projections that don't correspond to EPSG
>> codes.  It's not obvious to me how to proceed.
>>> Here is same server from agency where you work according your
>>> signature: maps.ngdc.noaa.gov/rest/services it provides additional
>>> maps on same server as arcgis
>>>
>>> I also checked many WMS servers, first with XML editor but then with
>>> Gaia, which was excellent help in determining that many WMS servers
>>> just return their capabilities, but does not provide service as
>>> described in capabilities response. Some offer tilling features, for
>>> possible future interactive zooming in Basemap ;)
>>
>> Maybe it's better not have the function accept a OWSLib wms object - that
>> way we don't have to tie ourselves to a particular WMS server.
>
> Thanks for explaining Jeff, but aren't we using arcgis REST service
> which accepts more then 4500 projections? Are you saying Basemap
> offers projection that's not listed here:
> http://atlas.resources.ca.gov/arcgis/SDK/REST/gcs.html

Klo:  Yes.  And vice versa, some of those 4500 projections aren't 
supported by Basemap.

Anyway, I went ahead and created a prototype 'wmsmap' method. You can 
try it by cloning my fork (https://github.com/jswhit/basemap) and 
running examples/testwms.py.  I created an extra kward 'epsg' for 
creating Basemap instances. To use the wmsmap function, you have to use 
that keyword.  Give it a try and let me know what you think.

-Jeff
>
> EPSG codes may be important to WMS. And providing WMS feature is maybe
> question how. Any GIS tool has WMS service support. Some WMS servers
> provide tiling capabilities and that also can be considered for future
> feature of fast zooming in Basemap. Most of them seem to offer just
> EPSG:4326 and there are servers with many projections (not as many as
> arcgis REST service)
> But at this point of static map servers we can just use urllib module
> and do requested WMS function which will return the map without using
> any additional function or package
>
> I'm validating public WMS servers and these days I'll report again. As
> mentioned many simply aren't working, many are localized, etc.
> Hope will find nice usage for some selected
>
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-- 
Jeffrey S. Whitaker         Phone  : (303)497-6313
Meteorologist               FAX    : (303)497-6449
NOAA/OAR/PSD  R/PSD1        Email  : Jef...@no...
325 Broadway                Office : Skaggs Research Cntr 1D-113
Boulder, CO, USA 80303-3328 Web    : http://tinyurl.com/5telg

We have a WMS server that uses basemap to display unstructured ocean model data. We just limit the set of projections to a select few (just the most common ones), and have a mapping between EPSG and the required Basemap kwargs. It sometimes requires some implementation of proj4 prior to getting to the Basemap part of the code. I can see that it could be useful and not to difficult to add an EPSG kwarg for a few most common projections and how they would be used by Basemap users.

Alexander Crosby
RPS-ASA

On Mon, 2012-08-27 at 06:34 -0600, Jeff Whitaker wrote:


On 8/26/12 9:07 PM, klo uo wrote:
> On Sun, Aug 26, 2012 at 9:56 PM, Jeff Whitaker wrote:
>> Klo:  Since epsg codes comprise a very small subset of possible Basemap
>> projections, it may be better to just allow Basemap to accept an epsg kwarg.
>> That keyword would be required in order to use a WMS to display a map
>> background. This may be tricky though, since Basemap needs more information
>> to define a map projection region than is provided by the epsg code.  We may
>> have to start with just a few supported epsg codes and then add more as
>> necessary.
>>
>> I added a testwms.py example to my fork
>> (https://github.com/jswhit/basemap.git) that shows how to use three
>> different map projections (epsg codes).
> I'm not sure if I understand projection problem, as arcgis webservice
> provides thousands of projections, but then you know better.
> I thought that the code will be just one function which would accept
> Map name, then coordinates and projection code will be deduced from
> Basemap function initiation?
Klo:  WMS servers use EPSG codes to define map projections - Basemap
uses a set of kwargs.  We need some way of inferring epsg codes from the
Basemap kwargs.  Alternatively, we could extend Basemap so it can accept
EPSG codes.  But, there are many EPSG codes that don't correspond to
allowable Basemap projections, and valid Basemap projections that don't
correspond to EPSG codes.  It's not obvious to me how to proceed.
>
> Here is same server from agency where you work according your
> signature: maps.ngdc.noaa.gov/rest/services it provides additional
> maps on same server as arcgis
>
> I also checked many WMS servers, first with XML editor but then with
> Gaia, which was excellent help in determining that many WMS servers
> just return their capabilities, but does not provide service as
> described in capabilities response. Some offer tilling features, for
> possible future interactive zooming in Basemap ;)

Maybe it's better not have the function accept a OWSLib wms object -
that way we don't have to tie ourselves to a particular WMS server.

-Jeff
>
> Here is one http://maps.dwd.de/geoserver/wms?request=GetCapabilities&service=WMS&version=1.1.1
> which offers bluemarble in many projection. Additionally it offers
> some German datasets, but does not offer tilling service.
>
> Perhaps we could look just for servers with get map service but also
> tilling support and support for various projections.
>
> ------------------------------------------------------------------------------
> Live Security Virtual Conference
> Exclusive live event will cover all the ways today's security and
> threat landscape has changed and how IT managers can respond. Discussions
> will include endpoint security, mobile security and the latest in malware
> threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/
> _______________________________________________
> Matplotlib-users mailing list
> Mat...@li...<mailto:Mat...@li...>
> https://lists.sourceforge.net/lists/listinfo/matplotlib-users


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On Mon, Aug 27, 2012 at 2:34 PM, Jeff Whitaker wrote:
> Klo:  WMS servers use EPSG codes to define map projections - Basemap uses a
> set of kwargs.  We need some way of inferring epsg codes from the Basemap
> kwargs.  Alternatively, we could extend Basemap so it can accept EPSG codes.
> But, there are many EPSG codes that don't correspond to allowable Basemap
> projections, and valid Basemap projections that don't correspond to EPSG
> codes.  It's not obvious to me how to proceed.
>>
>> Here is same server from agency where you work according your
>> signature: maps.ngdc.noaa.gov/rest/services it provides additional
>> maps on same server as arcgis
>>
>> I also checked many WMS servers, first with XML editor but then with
>> Gaia, which was excellent help in determining that many WMS servers
>> just return their capabilities, but does not provide service as
>> described in capabilities response. Some offer tilling features, for
>> possible future interactive zooming in Basemap ;)
>
>
> Maybe it's better not have the function accept a OWSLib wms object - that
> way we don't have to tie ourselves to a particular WMS server.


Thanks for explaining Jeff, but aren't we using arcgis REST service
which accepts more then 4500 projections? Are you saying Basemap
offers projection that's not listed here:
http://atlas.resources.ca.gov/arcgis/SDK/REST/gcs.html

EPSG codes may be important to WMS. And providing WMS feature is maybe
question how. Any GIS tool has WMS service support. Some WMS servers
provide tiling capabilities and that also can be considered for future
feature of fast zooming in Basemap. Most of them seem to offer just
EPSG:4326 and there are servers with many projections (not as many as
arcgis REST service)
But at this point of static map servers we can just use urllib module
and do requested WMS function which will return the map without using
any additional function or package

I'm validating public WMS servers and these days I'll report again. As
mentioned many simply aren't working, many are localized, etc.
Hope will find nice usage for some selected

________________________________
 From: Warren Weckesser <war...@en...>
To: "mat...@li..." <mat...@li...> 
Sent: Saturday, August 25, 2012 11:13 AM
Subject: Re: [Matplotlib-users] plotting a colored symbol with plot command
 




On Sat, Aug 25, 2012 at 9:59 AM, Michael Rawlins <raw...@ya...> wrote:


>
>
>
>
>________________________________
> From: Damon McDougall <dam...@gm...>
>To: Michael Rawlins <raw...@ya...> 
>Cc: "mat...@li..." <mat...@li...> 
>Sent: Saturday, August 25, 2012 4:21 AM
>Subject: Re: [Matplotlib-users] plotting a colored symbol with plot command
> 
>On Fri, Aug 24, 2012 at 02:39:12PM -0700, Michael Rawlins wrote:
>> 
>> 
>> 
>> 
>> ________________________________
>>  From: Damon McDougall <dam...@gm...>
>> To: Michael Rawlins <raw...@ya...> 
>> Cc: "mat...@li..." <mat...@li...> 
>> Sent: Friday, August 24, 2012 4:22 PM
>> Subject: Re: [Matplotlib-users] plotting a colored symbol with plot command
>>  
>> On Fri, Aug 24, 2012 at 09:20:47PM +0100,
 Damon McDougall wrote:
>
>> 
>> If I use plt.plot(x, y, color='g', marker='.', markersize=3.0)
>> 
>> the dots are black.
>
>That should not happen... Have you tried some of the other colours? 'r',
>'b', 'm', 'y', 'c'? Are they all black? What are you saving the file as? What
>is the output of:
>
>plt.get_backend()
>
>
>Yes I've tried several. All produce black dots. The output of that command is 'agg'.  I use:
>
>plt.savefig('map.eps')
>
>to produce eps images.
>
>


The default 'markeredgecolor' (or 'mec') is black, and with small dots, 
you will see more edge color than face color.  To test this, create the 
same plot but with an exaggerated marker size, e.g. markersize=30.  If 
that is the problem, you can fix it by also setting the edge color to 
green, e.g. mec='g'.

Warren


[Sending to the list this time--forgot to "reply to all" the first time.]


Success.  I've made the markers larger. The correct color is being plotted. As Warren suggested, without specifying markeredgecolor I see mostly black border with the smaller marker size. Thanks to all for the help.  


 
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Dear matplotlibers,

I encountered a bug (?) in fill_between when using logarithmic scales and
the last part of y and yerr arrays as set to zero: a diagonal stripe going from
the rightmost non zero value to the first value is drawn.
It's visible in the right panel of the attached figure, while is not
present if the plot is linear (left panel).
If xaxis is log and yaxis is linear the plot is correctly drawn.

I'm using mpl.__version__ = '1.1.1rc' under Kubuntu 12.04 with Python 2.7.3

The plot has been created with the script below.

Is this a bug or am I missing something?

Cheers
Francesco


##### error_fill_between.py ######
import matplotlib.pyplot as plt
import numpy as np

#values to plot
x = np.linspace( 1, 10, num=100 )
y = np.exp( -x**2 )
y[50:] = 0
yerr = y* np.random.rand(100)

#figure
fig = plt.figure()

ax1 = fig.add_subplot(121)  #first axes: linear
ax1.errorbar( x,y,yerr, c='r' )
ax1.fill_between( x,y-yerr,y+yerr, color='b', alpha=0.4 )

ax2 = fig.add_subplot(122)  #second axes: logarithmic
ax2.errorbar( x,y,yerr, c='r' )
ax2.fill_between( x,y-yerr,y+yerr, color='b', alpha=0.4 )
ax2.set_xscale( "log" )
ax2.set_yscale( "log" )

plt.show()
###### end script  #########

On 8/26/12 9:07 PM, klo uo wrote:
> On Sun, Aug 26, 2012 at 9:56 PM, Jeff Whitaker wrote:
>> Klo:  Since epsg codes comprise a very small subset of possible Basemap
>> projections, it may be better to just allow Basemap to accept an epsg kwarg.
>> That keyword would be required in order to use a WMS to display a map
>> background. This may be tricky though, since Basemap needs more information
>> to define a map projection region than is provided by the epsg code.  We may
>> have to start with just a few supported epsg codes and then add more as
>> necessary.
>>
>> I added a testwms.py example to my fork
>> (https://github.com/jswhit/basemap.git) that shows how to use three
>> different map projections (epsg codes).
> I'm not sure if I understand projection problem, as arcgis webservice
> provides thousands of projections, but then you know better.
> I thought that the code will be just one function which would accept
> Map name, then coordinates and projection code will be deduced from
> Basemap function initiation?
Klo:  WMS servers use EPSG codes to define map projections - Basemap 
uses a set of kwargs.  We need some way of inferring epsg codes from the 
Basemap kwargs.  Alternatively, we could extend Basemap so it can accept 
EPSG codes.  But, there are many EPSG codes that don't correspond to 
allowable Basemap projections, and valid Basemap projections that don't 
correspond to EPSG codes.  It's not obvious to me how to proceed.
>
> Here is same server from agency where you work according your
> signature: maps.ngdc.noaa.gov/rest/services it provides additional
> maps on same server as arcgis
>
> I also checked many WMS servers, first with XML editor but then with
> Gaia, which was excellent help in determining that many WMS servers
> just return their capabilities, but does not provide service as
> described in capabilities response. Some offer tilling features, for
> possible future interactive zooming in Basemap ;)

Maybe it's better not have the function accept a OWSLib wms object - 
that way we don't have to tie ourselves to a particular WMS server.

-Jeff
>
> Here is one http://maps.dwd.de/geoserver/wms?request=GetCapabilities&service=WMS&version=1.1.1
> which offers bluemarble in many projection. Additionally it offers
> some German datasets, but does not offer tilling service.
>
> Perhaps we could look just for servers with get map service but also
> tilling support and support for various projections.
>
> ------------------------------------------------------------------------------
> Live Security Virtual Conference
> Exclusive live event will cover all the ways today's security and
> threat landscape has changed and how IT managers can respond. Discussions
> will include endpoint security, mobile security and the latest in malware
> threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/
> _______________________________________________
> Matplotlib-users mailing list
> Mat...@li...
> https://lists.sourceforge.net/lists/listinfo/matplotlib-users

On Sun, Aug 26, 2012 at 9:56 PM, Jeff Whitaker wrote:
> Klo:  Since epsg codes comprise a very small subset of possible Basemap
> projections, it may be better to just allow Basemap to accept an epsg kwarg.
> That keyword would be required in order to use a WMS to display a map
> background. This may be tricky though, since Basemap needs more information
> to define a map projection region than is provided by the epsg code.  We may
> have to start with just a few supported epsg codes and then add more as
> necessary.
>
> I added a testwms.py example to my fork
> (https://github.com/jswhit/basemap.git) that shows how to use three
> different map projections (epsg codes).

I'm not sure if I understand projection problem, as arcgis webservice
provides thousands of projections, but then you know better.
I thought that the code will be just one function which would accept
Map name, then coordinates and projection code will be deduced from
Basemap function initiation?

Here is same server from agency where you work according your
signature: maps.ngdc.noaa.gov/rest/services it provides additional
maps on same server as arcgis

I also checked many WMS servers, first with XML editor but then with
Gaia, which was excellent help in determining that many WMS servers
just return their capabilities, but does not provide service as
described in capabilities response. Some offer tilling features, for
possible future interactive zooming in Basemap ;)

Here is one http://maps.dwd.de/geoserver/wms?request=GetCapabilities&service=WMS&version=1.1.1
which offers bluemarble in many projection. Additionally it offers
some German datasets, but does not offer tilling service.

Perhaps we could look just for servers with get map service but also
tilling support and support for various projections.