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On 4/2/12 4:02 PM, Mathew Topper wrote:
> On 02/04/12 19:09, Jeff Whitaker wrote:
>>
>> Mat:  I just updated git master to add the 'k_0' keyword when using 
>> projection='tmerc'.  This is the scaling factor along the central 
>> meridian, and is needed to exactly match the UTM definition.  I also 
>> added a utmtest.py example, that shows how to plot a UTM zone, and 
>> convert Basemap coordinates to UTM coordinates.
>>
>> -Jeff
>> -- 
>> 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
>
> Jeff, thanks again for all your help with this. I tried the example 
> and it works great. My only question would be how to get the axis 
> labels into meters rather than degrees. Any hints? I have found the 
> customticks.py example. Is that the best route to take?
Mat:  Just use 'suppress_ticks=False' when creating the Basemap 
instance, and you will get axis ticks in meters. If you want to use a 
custom tick formatter, use the customticks.py example as a guide.

-Jeff

-- 
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

Well, not sure if that is supported, but I found a way !:
        [...]

        self.fig1 = Figure(figsize=(width, height), dpi=dpi)
        self.fig2 = Figure(figsize=(width, height), dpi=dpi)
        self.axes1 = self.fig1.add_subplot(223)
        self.axes2 = self.fig2.add_subplot(221)

        [...]
        self.axes2.plot([0,1])
(1)     self.axes2.set_figure(self.fig1)
(2)     self.fig1.add_axes(self.axes2)

Note that (1) and (2) are required in that order!
From the code above, if I show the fig1, then I see axes1 and axes2 on the figure....


Summary:
I created the axes2 independently of fig1

PS: I want to use my axes2 as an object to sent to my Qt widget (a blank figure/canvas)

--
Emmanuel



________________________________
 From: Eric Firing <ef...@ha...>
To: mat...@li... 
Sent: Sunday, April 1, 2012 1:36 PM
Subject: Re: [Matplotlib-users] assigning a plot object to a figure
 
On 03/30/2012 01:23 PM, Emmanuel Mayssat wrote:
> Hello all,
>
> I can create a figure
> and get the corresponding axes/plots
>
> for examples:
> 1/
> fig = Figure(figsize=(width, height), dpi=dpi)
> ax = gif.add_subplot(111)
>
> 2/
> fig, ax = plt.subplots()
>
> but I would like to create my plot independently from the figure and
> assign it to a figure
>
> I code I would like to do something like this
>
> my_ax = Axes(...)
> my_ax.plot(x,y)
>
>
> ax = my_ax
>
> or
>
> my_ax.set_figure(fig)
>
> How can I create the axes/plot object independently from the figure?

As far as I can see, you can't.  The figure is deeply embedded in the 
Axes object; that's why the figure is an argument in Axes.__init__().

> Better yet, how can I assign an axe to a figure?

I don't think you can.  It looks to me like Axes.set_figure should be 
clearly marked as a private method, not to be used except in 
Axes.__init__().

Short of a major refactoring of mpl, I think you will need to find some 
other way of accomplishing your ultimate aim.

Eric

> --
> Emmanuel

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On 4/2/12 11:23 AM, Jeff Whitaker wrote:
> On 4/2/12 10:03 AM, Mathew Topper wrote:
>> On 02/04/12 16:21, Jeff Whitaker wrote:
>>> On 4/2/12 9:10 AM, Mathew Topper wrote:
>>>> Hi,
>>>>
>>>> I've been trawling round the internet for a while trying to work 
>>>> out if basemap could be made to plot using a UTM zone projection. 
>>>> I've found some references to pyproj that could be used to convert 
>>>> out of a UTM projection, but I haven't found any references to 
>>>> defining a custom projection for basemap. Is it possible?
>>>>
>>>> Also, there is not a lot of documentation regarding pyproj and I 
>>>> find this a little odd considering it comes packaged with basemap.
>>>>
>>>> Many Thanks,
>>>>
>>>> Mat
>>>
>>>
>>> Mat:  Basemap can plot in the tranverse mercator projection 
>>> (projecton='tmerc') - UTM zones are transverse mercator with 
>>> specific lat/lon boundaries and a WGS84 ellipsoid. I suppose I could 
>>> add UTM zone support if there is enough demand for it.
>>>
>>> -Jeff
>>> -- 
>>> 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
>>
>> OK, thanks Jeff. So I just need to know the lon/lat bounds of the 
>> desired UTM zone and I have effectively created a UTM projection of 
>> that zone in basemap i.e. for UTM29 we have 12W to 6W.
>> Will basemap then except coordinates in meters defined by UTM29 or do 
>> I have to convert to lon/lat first?
>
> Mat:  If you use projection='tmerc' and then give the lat/lon coords 
> of the upper right and lower left corners with 
> llcrnrlon,llcrnrlat,urcrnrlon,urcrnrlat, the projection coordinates 
> will be such that x,y = 0 in the lower left corner.  Since those will 
> not match the UTM coordinates exactly, you will have to add an offset 
> in x,y to make them match.
>
> -Jeff

Mat:  I just updated git master to add the 'k_0' keyword when using 
projection='tmerc'.  This is the scaling factor along the central 
meridian, and is needed to exactly match the UTM definition.  I also 
added a utmtest.py example, that shows how to plot a UTM zone, and 
convert Basemap coordinates to UTM coordinates.

-Jeff

-- 
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

On 4/2/12 10:03 AM, Mathew Topper wrote:
> On 02/04/12 16:21, Jeff Whitaker wrote:
>> On 4/2/12 9:10 AM, Mathew Topper wrote:
>>> Hi,
>>>
>>> I've been trawling round the internet for a while trying to work out 
>>> if basemap could be made to plot using a UTM zone projection. I've 
>>> found some references to pyproj that could be used to convert out of 
>>> a UTM projection, but I haven't found any references to defining a 
>>> custom projection for basemap. Is it possible?
>>>
>>> Also, there is not a lot of documentation regarding pyproj and I 
>>> find this a little odd considering it comes packaged with basemap.
>>>
>>> Many Thanks,
>>>
>>> Mat
>>
>>
>> Mat:  Basemap can plot in the tranverse mercator projection 
>> (projecton='tmerc') - UTM zones are transverse mercator with specific 
>> lat/lon boundaries and a WGS84 ellipsoid. I suppose I could add UTM 
>> zone support if there is enough demand for it.
>>
>> -Jeff
>> -- 
>> 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
>
> OK, thanks Jeff. So I just need to know the lon/lat bounds of the 
> desired UTM zone and I have effectively created a UTM projection of 
> that zone in basemap i.e. for UTM29 we have 12W to 6W.
> Will basemap then except coordinates in meters defined by UTM29 or do 
> I have to convert to lon/lat first?

Mat:  If you use projection='tmerc' and then give the lat/lon coords of 
the upper right and lower left corners with 
llcrnrlon,llcrnrlat,urcrnrlon,urcrnrlat, the projection coordinates will 
be such that x,y = 0 in the lower left corner.  Since those will not 
match the UTM coordinates exactly, you will have to add an offset in x,y 
to make them match.

-Jeff
>
> I have a bit of an interesting case where the region we are examining 
> lies between UTM29 and UTM30, and I was interested in displaying how 
> the change in projection effects the topography.
>
> Thanks
>
> Mat
> -- 
> Dr. Mathew Topper
> Institute for Energy Systems
> School of Engineering
> The University of Edinburgh
> Faraday Building
> The King's Buildings
> Edinburgh EH9 3JL
> Tel: +44 (0)131 650 5570
> School fax: +44 (0)131 650 6554
> mat...@ed... <mailto:mat...@ed...>
> http://www.see.ed.ac.uk <http://www.see.ed.ac.uk/>
>
>
> The University of Edinburgh is a charitable body, registered in
> Scotland, with registration number SC005336.
>
>
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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

The University of Edinburgh is a charitable body, registered in
Scotland, with registration number SC005336.

The University of Edinburgh is a charitable body, registered in
Scotland, with registration number SC005336.

On 4/2/12 9:10 AM, Mathew Topper wrote:
> Hi,
>
> I've been trawling round the internet for a while trying to work out 
> if basemap could be made to plot using a UTM zone projection. I've 
> found some references to pyproj that could be used to convert out of a 
> UTM projection, but I haven't found any references to defining a 
> custom projection for basemap. Is it possible?
>
> Also, there is not a lot of documentation regarding pyproj and I find 
> this a little odd considering it comes packaged with basemap.
>
> Many Thanks,
>
> Mat


Mat:  Basemap can plot in the tranverse mercator projection 
(projecton='tmerc') - UTM zones are transverse mercator with specific 
lat/lon boundaries and a WGS84 ellipsoid. I suppose I could add UTM zone 
support if there is enough demand for it.

-Jeff

-- 
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

The University of Edinburgh is a charitable body, registered in
Scotland, with registration number SC005336.

On 3/31/12 5:48 AM, David Craig wrote:
> Hi, I previously installed basemap by using the yum command. This 
> installed version 0.99.4. I want to install the latest version so I 
> can use shaded relief etc. This may be more of a linux problem but as 
> I am more familiar with python than linux I thought someone here may 
> be able to help.
> Following the website instructions 
> (http://matplotlib.github.com/basemap/users/installing.html) I 
> downloaded the latest version and untarred it. Then in the basemap 
> directory (which contains geos-3.2.0) I try to set the environment 
> variable GEOS_DIR to point to the location of libgeos_c and geos_c.h.
> I use the find command to locate the files,
> /find / -name geos_c.h/ returns the location of that file as 
> //usr/lib/basemap-1.0.1/geos-3.2.0/capi/geos_c.h/
> and
> /find / -name libgeos*/
> returns
> //libgeos_c_la-geos_c.Plo
> /usr/lib/libgeos-3.3.1.so <http://libgeos-3.3.1.so>
> /usr/lib/libgeos_c.so.1.7.1
> /usr/lib/libgeos_c.so.1/
> so I set GEOS_DIR to /usr/lib    (not sure if this is correct).
> I then cd to the basemap directory and run,
> python setup.py install
> [davcra@David basemap-1.0.1]$ sudo python setup.py install
> [sudo] password for davcra:
> checking for GEOS lib in /root ....
> checking for GEOS lib in /usr ....
> checking for GEOS lib in /usr/local ....
> checking for GEOS lib in /sw ....
> checking for GEOS lib in /opt ....
> checking for GEOS lib in /opt/local ....
>
> Can't find geos library . Please set the
> environment variable GEOS_DIR to point to the location
> where geos is installed (for example, if geos_c.h
> is in /usr/local/include, and libgeos_c is in /usr/local/lib,
> set GEOS_DIR to /usr/local), or edit the setup.py script
> manually and set the variable GEOS_dir (right after the line
> that says "set GEOS_dir manually here".
> The problem seems to be with GEOS_DIR but I am not sure what I should 
> set it to.
> Thanks
> D
David:

The basemap setup.py is assuming that the geos library is installed in 
<GEOS_DIR>/lib, and geos_c.h in <GEOS_DIR>/include.  You should set 
GEOS_DIR to the directory you specified with --prefix when you ran 
configure for geos 3.2.0 (I think the default is /usr/local).  However, 
it looks like you have a redhat installed geos library in /usr/lib 
(seems like it is version 3.3.1).  You probably could just install the 
-dev package (which would put the include file  in /usr/include), and 
the basemap setup.py would autodetect it.

Also, the latest version of basemap is 1.0.2, not 1.0.1.

-Jeff