I'm looking into the source of this bug now.
Mike
On 02/06/2012 09:19 AM, Jonathan Slavin wrote:
> Chris,
>
> You might want to try a module written by Tom Robitaille (aka astrofrog)
> called rasterized_scatter. Look for it on github.
>
> Jon
>
> On Mon, 2012-02-06 at 21:28 +0900, Jae-Joon Lee wrote:
>> Thanks. Now I understand the situation.
>>
>> As far as I can see, marker="," is implemented as a rectangle path
>> with width/height of 1 pixel, so this result in 2x2 pixel filled
>> square.
>> I tried to change the size of the rectangle, etc, to get a single
>> pixel filled square, but did not get a satisfactory result.
>> I think we need an Agg expert. I hope Mike or others take a look.
>>
>> Chris,
>> if you do not get a response from others in this mailing list, I
>> recommend you to open a new issue in our github page.
>>
>> Regards,
>>
>> -JJ
>>
>>
>> On Mon, Feb 6, 2012 at 1:53 AM, Chris<plut...@gmail.com> wrote:
>>> Thanks JJ.
>>>
>>> The problem seems not to be a size issue -- markersize has no effect
>>> when use marker="," (pixel). I have also tried to turn off aa, and it
>>> doesn't help either. I also tried different backends. The PNG output
>>> from Agg and Cairo is slightly different: Agg's point has 4 solid
>>> pixel, while Cairo's has 4 pixel with random shade.
>>>
>>> Postscript output has the same problem. The "pixel" in an EPS file
>>> generated by mpl is significantly bigger than that from another
>>> drawing program I used.
>>>
>>> The problem occurs in all my plotting scripts, e.g., this basic one:
>>>
>>> [CODE]
>>> import numpy as np
>>>
>>> x=np.arange(100)
>>> y=np.random.randn(100)
>>>
>>> ioff()
>>> fig=gcf()
>>> fig.clf()
>>>
>>> ax=fig.add_axes(0.15,0.1,0.8, 0.85)
>>> ax.plot(x,y,"k,")
>>>
>>> ion()
>>> fig.canvas.draw()
>>> [/CODE]
>>>
>>> Here is how I identify the problem:
>>> 1. use the above script to plot on screen
>>> 2. savefig("plot.png")
>>> 3. open plot.png in GIMP and check the pixel size.
>>>
>>> I also attached the two PNG files generated with Agg and Cairo backends.
>>>
>>>
>>> On Sun, Feb 5, 2012 at 6:45 AM, Jae-Joon Lee<lee.j.j...@gmail.com> wrote:
>>>> How are you plotting your points.
>>>>
>>>> If you use *plot*, there is a *markersize* parameter.
>>>> If you use *scatter*, the third argument controls the marker size.
>>>>
>>>> But you may actually complaining about other issues, e.g.,
>>>> antialiasing, etc. So, if above are not your answer, please post a
>>>> complete example and describe your problem in more detail.
>>>>
>>>> Regards,
>>>>
>>>> -JJ
>>>>
>>>>
>>>> On Sat, Feb 4, 2012 at 2:15 PM, Chris<plut...@gmail.com> wrote:
>>>>> I noticed this a few years back, but left it aside because most of the
>>>>> time I can live with it. Recently I need to make a few plots
>>>>> containing a few million points, and 4 pixels for a point is a
>>>>> disaster. So my question is why the pixel marker size is set at 4
>>>>> pixels? And is there anyway to change it to a single pixel?
>>>>>
>>>>> Thanks,
>>>>> Chris
>
> ------------------------------------------------------------------------------
> Try before you buy = See our experts in action!
> The most comprehensive online learning library for Microsoft developers
> is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3,
> Metro Style Apps, more. Free future releases when you subscribe now!
> http://p.sf.net/sfu/learndevnow-dev2
> _______________________________________________
> Matplotlib-users mailing list
> Matplotlib-users@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/matplotlib-users
------------------------------------------------------------------------------
Try before you buy = See our experts in action!
The most comprehensive online learning library for Microsoft developers
is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3,
Metro Style Apps, more. Free future releases when you subscribe now!
http://p.sf.net/sfu/learndevnow-dev2
_______________________________________________
Matplotlib-users mailing list
Matplotlib-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/matplotlib-users
