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---SNIP---
JW> I see nothing wrong. You probably want the lower right
JW> corner to be at 16 degrees, not the upper right.
Yes exactly, I would like to have the lower right corner to be at 16
degrees.
I can see the intersection points of parallel 50 with the meridians 14
and 16 and of the parallel 51 with the meridian 15 on the scanned
image of the map. Than I can (using some graphic editing software,
GIMP for example) find (determine) which pixels are representing these
int. points and cut the needed rectangle off the image (from the GIMP,
or directly in the code using the image "transform" method). This is
the way how to calibrate the picture (or how to set up the same
rectangle area on the picture and on the Basemap projection).
Petr
>>My map uses Transverse Mercator projection, the Lat. of origin is 50N
>>and the Long. of origin is 15E.
>> 
>>
JW> OK. You've defined the projection correctly then, but what do you want
JW> the lower left and upper right corners of the map to be?
JW> -Jeff

Petr wrote:
>
>JW> Petr:
>
>JW> I don't see the problem. Do you expect the meridians to be vertical 
>JW> lines? They won't be for a transverse mercator projection - they would
>JW> be for a regular mercator projection. What map projection does you 
>JW> scanned map use?
>
>JW> BTW: every time I reply to you your email bounces.
>
>JW> -Jeff
>
>Jeff,
>
>IMHO 15th meridian has to be (according to the Basemap settings in the
>code) parallel to the vertical sides of the picture (it is!) 
>
OK, I follow you so far.
>and the
>direction to the left side and to the right side has to be the same
>(it is not)!
> 
>
now you lost me. 
>So the picture is not! vertically symmetric (it is obvious if you
>check the top right and the top left corner of the picture in the
>attachment for example). There you can see the left most meridian (14)
>starts in the bottom left corner and goes up (slightly right). So I
>expect the right most meridian (16) to start in the bottom right
>corner and go up (slightly left). But.... :)
> 
>
The top right corner of the map is 16 degrees east - so the meridian 
starts there and then goes slightly east and off the map. That's why you 
don't see it. The 14 degree meridian starts at the lower left corner 
and bends slight east into the map region - so you can actually see it 
on the map. I see nothing wrong. You probably want the lower right 
corner to be at 16 degrees, not the upper right.
>My map uses Transverse Mercator projection, the Lat. of origin is 50N
>and the Long. of origin is 15E.
> 
>
OK. You've defined the projection correctly then, but what do you want 
the lower left and upper right corners of the map to be?
-Jeff
-- 
Jeffrey S. Whitaker Phone : (303)497-6313
Meteorologist FAX : (303)497-6449
NOAA/OAR/CDC R/CDC1 Email : Jef...@no...
325 Broadway Office : Skaggs Research Cntr 1D-124
Boulder, CO, USA 80303-3328 Web : http://tinyurl.com/5telg

JW> Petr Jakes wrote:
>>below code works for me. BUT!!!: I just wonder, why meridians are not
>>plotted symmetrically to the vertical axis. Because of that it will be
>>a little bit more difficult to adjust (calibrate) my map (picture)
>>properly. Try to run the code without an image (as it is) and
>>you will see it.
>> 
>>
JW> Petr:
JW> I don't see the problem. Do you expect the meridians to be vertical 
JW> lines? They won't be for a transverse mercator projection - they would
JW> be for a regular mercator projection. What map projection does you 
JW> scanned map use?
JW> BTW: every time I reply to you your email bounces.
JW> -Jeff
Jeff,
IMHO 15th meridian has to be (according to the Basemap settings in the
code) parallel to the vertical sides of the picture (it is!) and the
direction to the left side and to the right side has to be the same
(it is not)!
So the picture is not! vertically symmetric (it is obvious if you
check the top right and the top left corner of the picture in the
attachment for example). There you can see the left most meridian (14)
starts in the bottom left corner and goes up (slightly right). So I
expect the right most meridian (16) to start in the bottom right
corner and go up (slightly left). But.... :)
My map uses Transverse Mercator projection, the Lat. of origin is 50N
and the Long. of origin is 15E.
Petr
PS: this is the first time I have got reply from you directly to my mail box as
well. Nothing wrong with our mail server for a long time :) Maybe some
Internet mystery :))))) Or just wrong 'reply to' address.....

Petr Jakes wrote:
>below code works for me. BUT!!!: I just wonder, why meridians are not
>plotted symmetrically to the vertical axis. Because of that it will be
>a little bit more difficult to adjust (calibrate) my map (picture)
>properly. Try to run the code without an image (as it is) and
>you will see it.
> 
>
Petr:
I don't see the problem. Do you expect the meridians to be vertical 
lines? They won't be for a transverse mercator projection - they would 
be for a regular mercator projection. What map projection does you 
scanned map use?
BTW: every time I reply to you your email bounces.
-Jeff
-- 
Jeffrey S. Whitaker Phone : (303)497-6313
Meteorologist FAX : (303)497-6449
NOAA/OAR/CDC R/CDC1 Email : Jef...@no...
325 Broadway Office : Skaggs Research Cntr 1D-124
Boulder, CO, USA 80303-3328 Web : http://tinyurl.com/5telg

Jeff,
sorry I am bothering you with my postings :)
Maybe I am missing something, but your way looks too complicated to
me....
below code works for me. BUT!!!: I just wonder, why meridians are not
plotted symmetrically to the vertical axis. Because of that it will be
a little bit more difficult to adjust (calibrate) my map (picture)
properly. Try to run the code without an image (as it is) and
you will see it.
Anyway, if you think the following code is fundamentally correct, I
can post my experiences how to scan the paper map and how to
"calibrate" scanned picture, so it can be shown with the Basemap
coordinates properly.
Petr
=======================================
from matplotlib.toolkits.basemap import Basemap
from pylab import *
m = Basemap(llcrnrlon=14.,llcrnrlat=50,urcrnrlon=16.,urcrnrlat=51.,\
 resolution='c',area_thresh=10.,projection='tmerc',\
 lat_0=50.,lon_0=15.)
##import Image
##ima=Image.open('/root/Desktop/native_nslu2/sejmout0006.jpg')
##ima1=ima.transform((1545,1730),Image.QUAD, (0,209,0,1940,1535,1938,1530,207))
##im = m.imshow(ima1)
# draw parallels
delat = 0.2
circles = arange(50.,51.,delat)
m.drawparallels(circles,labels=[1,0,0,0],fontsize=10)
# draw meridians
delon = 0.25
meridians = arange(14,16,delon)
m.drawmeridians(meridians,labels=[0,0,1,0],fontsize=10)
title('Transverse Mercator Projection')
# print 'plotting Transverse Mercator example, close plot window to proceed ...'
show()

Hi again,
Will be better with a subject,
 (sorry for the pollution)
 I'm looking for a way to remove and/or control the properties (color,
thickness,...) of the lines (axis) around the graph.
I spent already quite some time to search a solution. I have found only o=
ne
comment on these lines in the multiline-plot wiki:
"It's on our list of things to change the way these axes lines are draw
so that you can remove it, but it isn't done yet"
Is this done now? Is there even a dirty trick to at least remove them?
Thanks,
David

Hi matplotlib users,
 I'm looking for a way to remove and/or control the properties (color,
thickness,...) of the lines (axis) around the graph.
I spent already quite some time to search a solution. I have found only o=
ne
comment on these lines in the multiline-plot wiki:
"It's on our list of things to change the way these axes lines are draw
so that you can remove it, but it isn't done yet"
Is this done now? Is there even a dirty trick to at least remove them?
Thanks,
David

Hi John,
Is it possible to change the attributes of a sub plot ?
Ideally, we could set:
 - the figure of a subplot.
 - the number of rows of a subplot.
 - the number of line of a subplot.
 - the position of a subplot
It could be very usefull.
regards,
Philippe Collet

Hi,
two bar plot questions from my side:
- Is it possible to draw bar plots without surronding lines? How?
- I'd like to draw the bars a bit transparent, but 'alpha' does not 
work. Is there an other way?
TIA
Christian

Brian,
The colorbar() function only works with things like images that use a 
colormap--that is, a function that maps an interval onto a range of 
colors, typically by linear interpolation. When you use set_facecolor, 
you are setting colors explicitly instead of having them calculated from 
a colormap. I've thought about extending the colorbar function so it 
could handle this case, but I haven't done it and probably won't within 
the next week or two.
Eric
> 
> I'm somewhat of a newbie and I have hopefully a simple question (people asking
> similar questions in the archive seem to be beyond this already). I have a
> working color fill generated using the set_facecolor command on a collection of
> polygons. When I try to use colorbar() I get the message: cmap = mappable.cmp 
> AttributeError: 'NoneType' object has no
> object 'cmap'. 
> 
> This question could be a little lacking in information? Maybe someone has a bit
> of sample code that already does something like this?
> 
> Thanks!
> 
> Brian