Matplotlib-users Digest, Vol 50, Issue 79

Hi Benjamim,

I made the changes as bellow and it displays the x-axis values formatted
as expected, see my current image and my code. But, now i need to change the scale and the numbers of decimal places in order to appear on
the graph like this: 3.0 3.1 3.2 … 3.4

My code: http://pastebin.com/vSbkXDzE

Can you help me?

Waleria

grafico.jpg

···

On Wed, Jul 28, 2010 at 8:41 PM, matplotlib-users-request@lists.sourceforge.net wrote:

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Today’s Topics:

  1. Re: hz to khz (Angus McMorland)

  2. Re: hz to khz (Benjamin Root)

  3. Arrow in log space (Thomas Robitaille)

  4. Re: Arrow in log space (Benjamin Root)

  5. Re: Confusion Matrix (Simon Friedberger)

  6. Re: Saving as eps file shifts image? (Jae-Joon Lee)


Message: 1

Date: Wed, 28 Jul 2010 15:39:29 -0400

From: Angus McMorland <amcmorl@…2015…87…>

Subject: Re: [Matplotlib-users] hz to khz

To: Matplotlib Users matplotlib-users@lists.sourceforge.net

Message-ID:

    <AANLkTinomazdZccuuKenq+C99Y+0EWC_o7O+6JPZqg3H@...83...288...>

Content-Type: text/plain; charset=ISO-8859-1

On 28 July 2010 15:25, Wal?ria Antunes David <waleriantunes@…287…> wrote:

Hello all,

Well, my problem is … My current code is as follow bellow:

http://pastebin.com/7p2N5d64

Hi Wal?ria,

We can’t easily fix your problem without knowing what data f and

Sserie contain. It would help us to help you if you could post a

standalone example that shows your problem without relying on external

data.

Angus.

AJC McMorland

Post-doctoral research fellow

Neurobiology, University of Pittsburgh


Message: 2

Date: Wed, 28 Jul 2010 14:59:35 -0500

From: Benjamin Root <ben.root@…83…1304…>

Subject: Re: [Matplotlib-users] hz to khz

To: Angus McMorland <amcmorl@…1972…>

Cc: Matplotlib Users matplotlib-users@lists.sourceforge.net

Message-ID:

    <AANLkTi=O73E3atkQprZO5_LMpfOu=72CNvJbLTSNnDUY@...288...>

Content-Type: text/plain; charset=“iso-8859-1”

On Wed, Jul 28, 2010 at 2:39 PM, Angus McMorland <amcmorl@…287…> wrote:

On 28 July 2010 15:25, Wal?ria Antunes David <waleriantunes@…287…> > > > wrote:

Hello all,

Well, my problem is … My current code is as follow bellow:

http://pastebin.com/7p2N5d64

Hi Wal?ria,

We can’t easily fix your problem without knowing what data f and

Sserie contain. It would help us to help you if you could post a

standalone example that shows your problem without relying on external

data.

Angus.

AJC McMorland

Post-doctoral research fellow

Neurobiology, University of Pittsburgh

Angus is correct that providing a stand-alone version of the script that

replicates your problem would be most useful. I would like to mention a

couple of possible improvements to your code. These improvements may or may

not fix your issue, but they will improve your current code.

  1. Use list comprehensions

Change

y=[]

for n in f:

y.append(n/Decimal(1000))

y = numpy.array(y)

into:

y = numpy.array(f) / 1000.0

Also,

ax.grid(‘TRUE’)

should be:

ax.grid(True)

I hope this helps. If not, then please send a stand-alone example that

duplicates the problem you are having.

Ben Root

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Message: 3

Date: Wed, 28 Jul 2010 16:56:41 -0400

From: Thomas Robitaille <thomas.robitaille@…287…>

Subject: [Matplotlib-users] Arrow in log space

To: matplotlib-users@lists.sourceforge.net

Message-ID: <FC45934C-52AA-4B5D-91B1-D155E7E753A8@…287…>

Content-Type: text/plain; charset=us-ascii

Hi,

How does one plot an arrow in a log log plot? In the following example, I can’t get the arrow head, regardless of what value I use for the head width:

import matplotlib as mpl

mpl.use(‘Agg’)

import matplotlib.pyplot as plt

fig = plt.figure()

ax = fig.add_subplot(1,1,1)

ax.arrow(0.2,0.2,0.5,0.5,head_width=1.)

ax.set_xscale(‘log’)

ax.set_yscale(‘log’)

ax.set_xlim(0.1,1.)

ax.set_ylim(0.1,1.)

fig.savefig(‘test.png’)

In addition, the documentation for arrow does not even mention any arrow specific options such as the head width/length, and the example plot is missing (there is a ‘Exception occurred rendering plot.’ message instead)

http://matplotlib.sourceforge.net/api/axes_api.html?highlight=arrow#matplotlib.axes.Axes.arrow

Thanks for any help,

Thomas


Message: 4

Date: Wed, 28 Jul 2010 16:45:39 -0500

From: Benjamin Root <ben.root@…83…1304…>

Subject: Re: [Matplotlib-users] Arrow in log space

To: Thomas Robitaille <thomas.robitaille@…287…>

Cc: matplotlib-users@lists.sourceforge.net

Message-ID:

    <AANLkTi=hCGCs9FVO0O6z=qVybsBMNwoBo=OW9f9wRw5t@...288...>

Content-Type: text/plain; charset=“iso-8859-1”

On Wed, Jul 28, 2010 at 3:56 PM, Thomas Robitaille < > > thomas.robitaille@…287…> wrote:

Hi,

How does one plot an arrow in a log log plot? In the following example, I

can’t get the arrow head, regardless of what value I use for the head width:

import matplotlib as mpl

mpl.use(‘Agg’)

import matplotlib.pyplot as plt

fig = plt.figure()

ax = fig.add_subplot(1,1,1)

ax.arrow(0.2,0.2,0.5,0.5,head_width=1.)

ax.set_xscale(‘log’)

ax.set_yscale(‘log’)

ax.set_xlim(0.1,1.)

ax.set_ylim(0.1,1.)

fig.savefig(‘test.png’)

In addition, the documentation for arrow does not even mention any arrow

specific options such as the head width/length, and the example plot is

missing (there is a ‘Exception occurred rendering plot.’ message instead)

http://matplotlib.sourceforge.net/api/axes_api.html?highlight=arrow#matplotlib.axes.Axes.arrow

Thanks for any help,

Thomas

I can’t say anything with regards to why your figure is not working, or why

the plot fails to render online (it renders just fine for myself when built

locally). However, I have noticed that the lack of information regarding

the options for arrow seems to be related to the docstring for arrow()

referring to the kwargs for FancyArrow, but none of those are defined. And

the docstring for FancyArrow appears to be incomplete.

Ben Root

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Message: 5

Date: Thu, 29 Jul 2010 00:04:41 +0200

From: Simon Friedberger <simon+matplotlib@…3202…>

Subject: Re: [Matplotlib-users] Confusion Matrix

To: matplotlib-users@lists.sourceforge.net

Message-ID: <20100728220441.GC1146@…3202…>

Content-Type: text/plain; charset=us-ascii

On 18:32 Sun 18.07.10, Friedrich Romstedt wrote:

Try to add:

ax.set_xticks(range(0, 10))

ax.set_yticks(range(0, 10))

before the imshow call.

For some reason it must happen before the imshow call and not after,

else the yscaling will change (I don’t understand this).

Thanks for this tip. Apparently there is a necessary order for some calls.

Is this documented anywhere? It seems quite problematic.

Also I have now finished my confusion matrix program:

http://paste.pocoo.org/show/242834/

Comments on the code would be very welcome.

If people like it maybe it could be included in the examples. I think it’s a

relatively common usecase.

Regards

Simon


Message: 6

Date: Thu, 29 Jul 2010 08:40:54 +0900

From: Jae-Joon Lee <lee.j.joon@…120…287…>

Subject: Re: [Matplotlib-users] Saving as eps file shifts image?

To: “Jenna L.” <jenna@…2015…124…>

Cc: matplotlib-users@lists.sourceforge.net

Message-ID:

    <AANLkTik-TQ9iwoZheH6_Aa2XOheMbiXtLhTGX7WhVO3P@...288...>

Content-Type: text/plain; charset=“utf-8”

On Thu, Jul 29, 2010 at 1:17 AM, Jenna L. <jenna@…2124…> wrote:

That looks fine to me too, but if you plot that as one subplot in a 5x5 array

of subplots or more, then you can see the shift I am talking about in the

eps file. ?Example:

I still don’t see it (a capture of my eps output is attached).

Can you post your output (original eps file that shows the shift)?

Again, what is your matplotlib version?

Regards,

-JJ

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End of Matplotlib-users Digest, Vol 50, Issue 79


What do you mean by "change the scale"?

···

On 29/07/10 12:45, Wal�ria Antunes David wrote:

Hi Benjamim,

I made the changes as bellow and it displays the x-axis values formatted as
expected, see my current image and my code. But, now i need to change the
scale and the numbers of decimal places in order to appear on the graph like
this: 3.0 3.1 3.2 ...... 3.4

My code: http://pastebin.com/vSbkXDzE

Can you help me?

Waleria

Hi

I made the changes as bellow and it displays the x-axis values formatted
as expected, see my current image and my code. But, now i need to change the scale and the numbers of decimal places in order to appear on
the graph like this: 3.0 3.1 3.2 … 3.4

My code: http://pastebin.com/vSbkXDzE

Can you help me?

Waleria

Send Matplotlib-users mailing list submissions to

    matplotlib-users@lists.sourceforge.net

To subscribe or unsubscribe via the World Wide Web, visit

    [https://lists.sourceforge.net/lists/listinfo/matplotlib-users](https://lists.sourceforge.net/lists/listinfo/matplotlib-users)

or, via email, send a message with subject or body ‘help’ to

    matplotlib-users-request@lists.sourceforge.net

You can reach the person managing the list at

    matplotlib-users-owner@lists.sourceforge.net

When replying, please edit your Subject line so it is more specific

than “Re: Contents of Matplotlib-users digest…”

Today’s Topics:

  1. Re: hz to khz (Angus McMorland)

  2. Re: hz to khz (Benjamin Root)

  3. Arrow in log space (Thomas Robitaille)

  4. Re: Arrow in log space (Benjamin Root)

  5. Re: Confusion Matrix (Simon Friedberger)

  6. Re: Saving as eps file shifts image? (Jae-Joon Lee)


Message: 1

Date: Wed, 28 Jul 2010 15:39:29 -0400

From: Angus McMorland <amcmorl@…287…>

Subject: Re: [Matplotlib-users] hz to khz

To: Matplotlib Users matplotlib-users@lists.sourceforge.net

Message-ID:

    <AANLkTinomazdZccuuKenq+C99Y+0EWC_o7O+6JPZqg3H@...288...>

Content-Type: text/plain; charset=ISO-8859-1

Hello all,

Well, my problem is … My current code is as follow bellow:

http://pastebin.com/7p2N5d64

Hi Wal?ria,

We can’t easily fix your problem without knowing what data f and

Sserie contain. It would help us to help you if you could post a

standalone example that shows your problem without relying on external

data.

Angus.

AJC McMorland

Post-doctoral research fellow

Neurobiology, University of Pittsburgh


Message: 2

Date: Wed, 28 Jul 2010 14:59:35 -0500

From: Benjamin Root <ben.root@…1304…>

Subject: Re: [Matplotlib-users] hz to khz

To: Angus McMorland <amcmorl@…287…>

Cc: Matplotlib Users matplotlib-users@lists.sourceforge.net

Message-ID:

    <AANLkTi=O73E3atkQprZO5_LMpfOu=72CNvJbLTSNnDUY@...288...>

Content-Type: text/plain; charset=“iso-8859-1”

Hello all,

Well, my problem is … My current code is as follow bellow:

http://pastebin.com/7p2N5d64

Hi Wal?ria,

We can’t easily fix your problem without knowing what data f and

Sserie contain. It would help us to help you if you could post a

standalone example that shows your problem without relying on external

data.

Angus.

AJC McMorland

Post-doctoral research fellow

Neurobiology, University of Pittsburgh

Angus is correct that providing a stand-alone version of the script that

replicates your problem would be most useful. I would like to mention a

couple of possible improvements to your code. These improvements may or may

not fix your issue, but they will improve your current code.

  1. Use list comprehensions

Change

y=[]

for n in f:

y.append(n/Decimal(1000))

y = numpy.array(y)

into:

y = numpy.array(f) / 1000.0

Also,

ax.grid(‘TRUE’)

should be:

ax.grid(True)

I hope this helps. If not, then please send a stand-alone example that

duplicates the problem you are having.

Ben Root

-------------- next part --------------

An HTML attachment was scrubbed…


Message: 3

Date: Wed, 28 Jul 2010 16:56:41 -0400

From: Thomas Robitaille <thomas.robitaille@…287…>

Subject: [Matplotlib-users] Arrow in log space

To: matplotlib-users@lists.sourceforge.net

Message-ID: <FC45934C-52AA-4B5D-91B1-D155E7E753A8@…287…>

Content-Type: text/plain; charset=us-ascii

Hi,

How does one plot an arrow in a log log plot? In the following example, I can’t get the arrow head, regardless of what value I use for the head width:

import matplotlib as mpl

mpl.use(‘Agg’)

import matplotlib.pyplot as plt

fig = plt.figure()

ax = fig.add_subplot(1,1,1)

ax.arrow(0.2,0.2,0.5,0.5,head_width=1.)

ax.set_xscale(‘log’)

ax.set_yscale(‘log’)

ax.set_xlim(0.1,1.)

ax.set_ylim(0.1,1.)

fig.savefig(‘test.png’)

In addition, the documentation for arrow does not even mention any arrow specific options such as the head width/length, and the example plot is missing (there is a ‘Exception occurred rendering plot.’ message instead)

http://matplotlib.sourceforge.net/api/axes_api.html?highlight=arrow#matplotlib.axes.Axes.arrow

Thanks for any help,

Thomas


Message: 4

Date: Wed, 28 Jul 2010 16:45:39 -0500

From: Benjamin Root <ben.root@…1304…>

Subject: Re: [Matplotlib-users] Arrow in log space

To: Thomas Robitaille <thomas.robitaille@…287…>

Cc: matplotlib-users@lists.sourceforge.net

Message-ID:

    <AANLkTi=hCGCs9FVO0O6z=qVybsBMNwoBo=OW9f9wRw5t@...288...>

Content-Type: text/plain; charset=“iso-8859-1”

Hi,

How does one plot an arrow in a log log plot? In the following example, I

can’t get the arrow head, regardless of what value I use for the head width:

import matplotlib as mpl

mpl.use(‘Agg’)

import matplotlib.pyplot as plt

fig = plt.figure()

ax = fig.add_subplot(1,1,1)

ax.arrow(0.2,0.2,0.5,0.5,head_width=1.)

ax.set_xscale(‘log’)

ax.set_yscale(‘log’)

ax.set_xlim(0.1,1.)

ax.set_ylim(0.1,1.)

fig.savefig(‘test.png’)

In addition, the documentation for arrow does not even mention any arrow

specific options such as the head width/length, and the example plot is

missing (there is a ‘Exception occurred rendering plot.’ message instead)

http://matplotlib.sourceforge.net/api/axes_api.html?highlight=arrow#matplotlib.axes.Axes.arrow

Thanks for any help,

Thomas

I can’t say anything with regards to why your figure is not working, or why

the plot fails to render online (it renders just fine for myself when built

locally). However, I have noticed that the lack of information regarding

the options for arrow seems to be related to the docstring for arrow()

referring to the kwargs for FancyArrow, but none of those are defined. And

the docstring for FancyArrow appears to be incomplete.

Ben Root

-------------- next part --------------

An HTML attachment was scrubbed…


Message: 5

Date: Thu, 29 Jul 2010 00:04:41 +0200

From: Simon Friedberger <simon+matplotlib@…3202…>

Subject: Re: [Matplotlib-users] Confusion Matrix

To: matplotlib-users@lists.sourceforge.net

Message-ID: <20100728220441.GC1146@…3202…>

Content-Type: text/plain; charset=us-ascii

Try to add:

ax.set_xticks(range(0, 10))

ax.set_yticks(range(0, 10))

before the imshow call.

For some reason it must happen before the imshow call and not after,

else the yscaling will change (I don’t understand this).

Thanks for this tip. Apparently there is a necessary order for some calls.

Is this documented anywhere? It seems quite problematic.

Also I have now finished my confusion matrix program:

http://paste.pocoo.org/show/242834/

Comments on the code would be very welcome.

If people like it maybe it could be included in the examples. I think it’s a

relatively common usecase.

Regards

Simon


Message: 6

Date: Thu, 29 Jul 2010 08:40:54 +0900

From: Jae-Joon Lee <lee.j.joon@…287…>

Subject: Re: [Matplotlib-users] Saving as eps file shifts image?

To: “Jenna L.” <jenna@…2124…>

Cc: matplotlib-users@lists.sourceforge.net

Message-ID:

    <AANLkTik-TQ9iwoZheH6_Aa2XOheMbiXtLhTGX7WhVO3P@...288...>

Content-Type: text/plain; charset=“utf-8”

That looks fine to me too, but if you plot that as one subplot in a 5x5 array

of subplots or more, then you can see the shift I am talking about in the

eps file. ?Example:

I still don’t see it (a capture of my eps output is attached).

Can you post your output (original eps file that shows the shift)?

Again, what is your matplotlib version?

Regards,

-JJ

-------------- next part --------------

A non-text attachment was scrubbed…

Name: image_shift_test.png

Type: image/png

Size: 13176 bytes

Desc: not available



The Palm PDK Hot Apps Program offers developers who use the

Plug-In Development Kit to bring their C/C++ apps to Palm for a share

of $1 Million in cash or HP Products. Visit us here for more details:

http://p.sf.net/sfu/dev2dev-palm



Matplotlib-users mailing list

Matplotlib-users@lists.sourceforge.net

https://lists.sourceforge.net/lists/listinfo/matplotlib-users

End of Matplotlib-users Digest, Vol 50, Issue 79


···

On Thu, Jul 29, 2010 at 8:45 AM, Waléria Antunes David <waleriantunes@…287…> wrote:

On Wed, Jul 28, 2010 at 8:41 PM, matplotlib-users-request@lists.sourceforge.net wrote:

On 28 July 2010 15:25, Wal?ria Antunes David <waleriantunes@…287…> wrote:
On Wed, Jul 28, 2010 at 2:39 PM, Angus McMorland <amcmorl@…287…> wrote:

On 28 July 2010 15:25, Wal?ria Antunes David <waleriantunes@…287…> > > > > > wrote:
On Wed, Jul 28, 2010 at 3:56 PM, Thomas Robitaille < > > > > thomas.robitaille@…287…> wrote:
On 18:32 Sun 18.07.10, Friedrich Romstedt wrote:
On Thu, Jul 29, 2010 at 1:17 AM, Jenna L. <jenna@…2124…> wrote:

2010/7/29 Waléria Antunes David <waleriantunes@...287...>:

Hi Benjamim,

I made the changes as bellow and it displays the x-axis values formatted as
expected, see my current image and my code. But, now i need to change the
scale and the numbers of decimal places in order to appear on the graph like
this: 3.0 3.1 3.2 ...... 3.4

I think you need:

import matplotlib.ticker
[...]
axes.xaxis.set_major_locator(matplotlib.ticker.MaxNLocator(nbins=4)

maybe with an additional argument steps=[1, 2, 5, 10] as done by AutoLocator.

Your pastebin code has expired, so I don't know how your variables are
named now.

Friedrich