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Dear Benjamin,

Thanks for the reply. Apparently my Python 2.6 version was completely
removed and I only have Python 2.7. My matplotlib and numpy are the latest
versions. In matplotlib homepage, I found that meshgrid should do the same
job, but I cannot make script to run it from a file. Is there a simple way
to do contour plotting on a simple 3 column file (x, y, z) where I gave a
link to the table file in my previous email?

Thanks a lot

Umut



> First, if you were importing griddata before like that, that it is quite
> likely that it was some other module that was installed in your
> python-2.6/site-packages directory that overrode numpy's griddata. When you
> upgraded, that griddata module could not be found in
> python-2.7/site-packages. Commenting it out allowed python to find pylab's
> griddata.
>
> Second, you really need to clean up your imports. There is no need for the
> two math imports, or the numpy import (because the pylab import handles
> that).
>
> Oddly, though, your griddata import comes before the pylab import. I would
> expect that the pylab griddata would have overridden the first griddata
> import. And so there shouldn't have been a difference.
>
> Did you happen to upgrade matplotlib and/or numpy as well?
>
> Ben Root
>
>

2012/5/29 Fabien Lafont <laf...@gm...>:
> Thx Francesco, it works great!
>
> What for the .T at the end of genfromtxt?

genfromtxt with usecols=(0,1) return an array with 2 columns. with .T
you transpose it so that you can save it in two variables. For more
info, e.g., http://docs.scipy.org/doc/numpy/reference/generated/numpy.ndarray.T.html#numpy-ndarray-t

Cheers,
Francesco

>
>
>
> 2012/5/29 Francesco Montesano <fra...@go...>:
>> Dear Fabien
>>
>> 2012/5/29 Fabien Lafont <laf...@gm...>:
>>> Hello everyone,
>>>
>>> I have a problem. I have to look at many plots. Usely I do it like that:
>>>
>>> from pylab import*
>>>
>>> X1 = genfromtxt("Myfile.dat", usecols =(0))
>>> Y1 = genfromtxt("Myfile.dat", usecols =(1))
>>> plot(X1,Y1, label ="My curve")
>>>
>>> show()
>>>
>>>
>>> But the problem is when I have many plots I have to copy paste and
>>> change manually all the name of the variables X1, X2, X3...etc. It's
>>> not really convenient.
>>> I want to create a def with the name of my file as argument which do
>>> something like that:
>>>
>>> from pylab import*
>>>
>>> def plotgraph(name):
>>>    X_name = genfromtxt("name", usecols =(0))
>>>    Y_name = genfromtxt("name", usecols =(1))
>>>    plot(X_name,Y_name, label ="name")
>>>
>>> plotgraph(MyFile)
>>>
>>> show()
>>>
>>
>> Try this:
>>
>> def plotgraph(name):
>>   """Plot stuff:
>>   name: string
>>     file name
>>   """
>>   X_name, Y_name = genfromtxt(name, usecols =(0,1)).T
>>   plot(X_name,Y_name, label =name)
>>
>> 'name' should contain already a string, so you have to pass it to
>> genfromtxt. I you pass "name", the file name is "name" and not the
>> what is in the variable.
>> Just a note: if you read the file as 'X_name, Y_name =
>> genfromtxt(name, usecols =(0,1)).T'  you open, read and close the file
>> only once.
>>
>> Cheers,
>> Francesco
>>
>>
>>> But it doesn't work. Do you know why? Do you have a smarter idea?
>>>
>>> Thanks!
>>>
>>> Fab
>>>
>>> ------------------------------------------------------------------------------
>>> 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/
>>> _______________________________________________
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>>> Mat...@li...
>>> https://lists.sourceforge.net/lists/listinfo/matplotlib-users
>>
>>
>>
>> --
>> personals: mon...@ya..., mon...@ho... (messenger),
>> fra...@go....
>> work: mon...@mp...
>>
>> http://picasaweb.google.it/franz.bergesund



-- 
personals: mon...@ya..., mon...@ho... (messenger),
fra...@go....
work: mon...@mp...

http://picasaweb.google.it/franz.bergesund

Thx Francesco, it works great!

What for the .T at the end of genfromtxt?



2012/5/29 Francesco Montesano <fra...@go...>:
> Dear Fabien
>
> 2012/5/29 Fabien Lafont <laf...@gm...>:
>> Hello everyone,
>>
>> I have a problem. I have to look at many plots. Usely I do it like that:
>>
>> from pylab import*
>>
>> X1 = genfromtxt("Myfile.dat", usecols =(0))
>> Y1 = genfromtxt("Myfile.dat", usecols =(1))
>> plot(X1,Y1, label ="My curve")
>>
>> show()
>>
>>
>> But the problem is when I have many plots I have to copy paste and
>> change manually all the name of the variables X1, X2, X3...etc. It's
>> not really convenient.
>> I want to create a def with the name of my file as argument which do
>> something like that:
>>
>> from pylab import*
>>
>> def plotgraph(name):
>>    X_name = genfromtxt("name", usecols =(0))
>>    Y_name = genfromtxt("name", usecols =(1))
>>    plot(X_name,Y_name, label ="name")
>>
>> plotgraph(MyFile)
>>
>> show()
>>
>
> Try this:
>
> def plotgraph(name):
>   """Plot stuff:
>   name: string
>     file name
>   """
>   X_name, Y_name = genfromtxt(name, usecols =(0,1)).T
>   plot(X_name,Y_name, label =name)
>
> 'name' should contain already a string, so you have to pass it to
> genfromtxt. I you pass "name", the file name is "name" and not the
> what is in the variable.
> Just a note: if you read the file as 'X_name, Y_name =
> genfromtxt(name, usecols =(0,1)).T'  you open, read and close the file
> only once.
>
> Cheers,
> Francesco
>
>
>> But it doesn't work. Do you know why? Do you have a smarter idea?
>>
>> Thanks!
>>
>> Fab
>>
>> ------------------------------------------------------------------------------
>> 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
>
>
>
> --
> personals: mon...@ya..., mon...@ho... (messenger),
> fra...@go....
> work: mon...@mp...
>
> http://picasaweb.google.it/franz.bergesund

Dear Fabien

2012/5/29 Fabien Lafont <laf...@gm...>:
> Hello everyone,
>
> I have a problem. I have to look at many plots. Usely I do it like that:
>
> from pylab import*
>
> X1 = genfromtxt("Myfile.dat", usecols =(0))
> Y1 = genfromtxt("Myfile.dat", usecols =(1))
> plot(X1,Y1, label ="My curve")
>
> show()
>
>
> But the problem is when I have many plots I have to copy paste and
> change manually all the name of the variables X1, X2, X3...etc. It's
> not really convenient.
> I want to create a def with the name of my file as argument which do
> something like that:
>
> from pylab import*
>
> def plotgraph(name):
>    X_name = genfromtxt("name", usecols =(0))
>    Y_name = genfromtxt("name", usecols =(1))
>    plot(X_name,Y_name, label ="name")
>
> plotgraph(MyFile)
>
> show()
>

Try this:

def plotgraph(name):
   """Plot stuff:
   name: string
     file name
   """
   X_name, Y_name = genfromtxt(name, usecols =(0,1)).T
   plot(X_name,Y_name, label =name)

'name' should contain already a string, so you have to pass it to
genfromtxt. I you pass "name", the file name is "name" and not the
what is in the variable.
Just a note: if you read the file as 'X_name, Y_name =
genfromtxt(name, usecols =(0,1)).T'  you open, read and close the file
only once.

Cheers,
Francesco


> But it doesn't work. Do you know why? Do you have a smarter idea?
>
> Thanks!
>
> Fab
>
> ------------------------------------------------------------------------------
> 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



-- 
personals: mon...@ya..., mon...@ho... (messenger),
fra...@go....
work: mon...@mp...

http://picasaweb.google.it/franz.bergesund

Hello everyone,

I have a problem. I have to look at many plots. Usely I do it like that:

from pylab import*

X1 = genfromtxt("Myfile.dat", usecols =(0))
Y1 = genfromtxt("Myfile.dat", usecols =(1))
plot(X1,Y1, label ="My curve")

show()


But the problem is when I have many plots I have to copy paste and
change manually all the name of the variables X1, X2, X3...etc. It's
not really convenient.
I want to create a def with the name of my file as argument which do
something like that:

from pylab import*

def plotgraph(name):
    X_name = genfromtxt("name", usecols =(0))
    Y_name = genfromtxt("name", usecols =(1))
    plot(X_name,Y_name, label ="name")

plotgraph(MyFile)

show()

But it doesn't work. Do you know why? Do you have a smarter idea?

Thanks!

Fab

Hi. I want to make sure how imshow shows a numpy array as image.

lets say below is our numpy data array where letter represent data values
and numbers represent row/col indices.

  0 1 2
0 a b c
1 d e f
2 g h i

and lets think imshow's origin is default upper left.
Now, if we show our data as an image, the orientation of visual
representation of data shouldt change,
and seen like below, right?

  0 1 2
0 a b c
1 d e f
2 g h i

But if we pass origin="lower" keyword to imshow, (as in basemap by default);
is this what we expect to see ?

  0 1 2
2 g h i
1 d e f
0 a b c

To be clear, does imshow with "lower" keyword value;

1-takes first row of data and put it most bottom,
2-then take second row and put it one row upper from most bottom.....etc ?

Thanks.

-- 
Yasin Selçuk Berber
"Bismillah, her hayrın başıdır."

On 12-02-07 08:40 AM, Michael Droettboom wrote:
> On 02/07/2012 10:48 AM, Benjamin Root wrote:
>>
>>
>> On Tue, Feb 7, 2012 at 8:33 AM, Fabien Lafont
>> <laf...@gm...
>> <mailto:laf...@gm...>> wrote:
>>
>>     Is it possible to set the extension .pdf as defaut when I save an
>>     image using the matplotlib bar. My coworkers are always saving the
>>     image in png and it's really ugly!
>>
>>     Thx,
>>
>>     Fab
>>
>>
>> Interesting request. Looking through the backends, it appears that only the
>> Cairo backend currently supports a configurable rcParam for the default
>> filetype ('cairo.format'). All backends implement a "get_default_filetype()"
>> method for their canvases, but most of them have that default hard-coded as
>> "png". This really only makes sense for backends like agg, pdf, ps and such.
>>
>> Devs - Maybe we should consider fixing this for the non-fileformat specific
>> backends? Do we want an rcParam for each backend? Or a single rcParam for
>> default filetypes and deprecate 'cairo.format'?
>
> I would definitely lean toward the latter -- unify it under a single rcParam.
>
> Mike

Sorry for posting to an old thread, but I just submitted a pull request that 
implements this, AFAICT:

https://github.com/matplotlib/matplotlib/pull/907

Martin