matplotlib-users

[Matplotlib-users] rectangular bracket in mathtext

[Matthias M. <Mat...@gm...>]

Hello list,

the little example below leads to an error on my system (output is attached).
I used this some time ago and it worked. Now I'm using the release 0.91.2.
Is there a reason to use rectangular brackets not in mathtext?
(same problem occur with '{' for me.)

best regards and thanks in advance for any help,
Matthias
-------------------------------------------------------------------------------------------------
import matplotlib.pyplot as mpl_pp
mpl_pp.axes()
mpl_pp.xlabel("$[$")
mpl_pp.show()

Re: [Matplotlib-users] rectangular bracket in mathtext

[Michael D. <md...@st...>]

You need to escape the [:

   mpl_pp.xlabel(r"$\[$")

[] and {} have special meanings in math syntax, so to use them 
"literally", they need to be escaped.

Cheers,
Mike

Matthias Michler wrote:
> Hello list,
> 
> the little example below leads to an error on my system (output is attached).
> I used this some time ago and it worked. Now I'm using the release 0.91.2.
> Is there a reason to use rectangular brackets not in mathtext?
> (same problem occur with '{' for me.)
> 
> best regards and thanks in advance for any help,
> Matthias
> -------------------------------------------------------------------------------------------------
> import matplotlib.pyplot as mpl_pp
> mpl_pp.axes()
> mpl_pp.xlabel("$[$")
> mpl_pp.show()
> 
> 
> ------------------------------------------------------------------------
> 
> -------------------------------------------------------------------------
> Check out the new SourceForge.net Marketplace.
> It's the best place to buy or sell services for
> just about anything Open Source.
> http://ad.doubleclick.net/clk;164216239;13503038;w?http://sf.net/marketplace
> 
> 
> ------------------------------------------------------------------------
> 
> _______________________________________________
> Matplotlib-users mailing list
> Mat...@li...
> https://lists.sourceforge.net/lists/listinfo/matplotlib-users

-- 
Michael Droettboom
Science Software Branch
Operations and Engineering Division
Space Telescope Science Institute
Operated by AURA for NASA

Re: [Matplotlib-users] rectangular bracket in mathtext

[Manuel M. <mm...@as...>]

Michael Droettboom wrote:
> You need to escape the [:
> 
>    mpl_pp.xlabel(r"$\[$")
> 
> [] and {} have special meanings in math syntax, so to use them 
> "literally", they need to be escaped.

Really? Note that Matthias had text.usetex=False.
I tried various configurations:

text.usetex=True

   xlabel( "$[$")     okay
   xlabel(r"$\[$")    okay
   xlabel( "$\[$")    no error, but also no label displayed


text.usetex=False

   xlabel("$[$")      failed with
       Expected end of text (at char 0), (line:1, col:1)

   xlabel(r"$\[$")
   xlabel( "$\[$")    no error, but displays a star symbol

In the last two cases I got a warning

mathtext.py:722: MathTextWarning: Unrecognized symbol '\['. Substituting 
with a dummy symbol.
   % sym.encode('ascii', 'backslashreplace'), MathTextWarning)

Cheers,
Manuel

> Cheers,
> Mike
> 
> Matthias Michler wrote:
>> Hello list,
>>
>> the little example below leads to an error on my system (output is attached).
>> I used this some time ago and it worked. Now I'm using the release 0.91.2.
>> Is there a reason to use rectangular brackets not in mathtext?
>> (same problem occur with '{' for me.)
>>
>> best regards and thanks in advance for any help,
>> Matthias
>> -------------------------------------------------------------------------------------------------
>> import matplotlib.pyplot as mpl_pp
>> mpl_pp.axes()
>> mpl_pp.xlabel("$[$")
>> mpl_pp.show()
>>
>>
>> ------------------------------------------------------------------------
>>
>> -------------------------------------------------------------------------
>> Check out the new SourceForge.net Marketplace.
>> It's the best place to buy or sell services for
>> just about anything Open Source.
>> http://ad.doubleclick.net/clk;164216239;13503038;w?http://sf.net/marketplace
>>
>>
>> ------------------------------------------------------------------------
>>
>> _______________________________________________
>> Matplotlib-users mailing list
>> Mat...@li...
>> https://lists.sourceforge.net/lists/listinfo/matplotlib-users
> 

Re: [Matplotlib-users] rectangular bracket in mathtext

[Michael D. <md...@st...>]

You're right.  It's a bug.  The parser (when it was re-written) was 
changed to not accept '[' as a literal symbol, since it is meaningful in 
certain situations.  This turned out to be overly cautious.  This is 
fixed in svn r4854.

Manuel Metz wrote:
> Michael Droettboom wrote:
>> You need to escape the [:
>>
>>    mpl_pp.xlabel(r"$\[$")
>>
>> [] and {} have special meanings in math syntax, so to use them 
>> "literally", they need to be escaped.
> 
> Really? Note that Matthias had text.usetex=False.
> I tried various configurations:
> 
> text.usetex=True
> 
>   xlabel( "$[$")     okay
>   xlabel(r"$\[$")    okay
>   xlabel( "$\[$")    no error, but also no label displayed

I'm surprised by this.  Those last two strings should be identical. 
Maybe Python 2.5 works differently from whatever you're running.

> text.usetex=False
> 
>   xlabel("$[$")      failed with
>       Expected end of text (at char 0), (line:1, col:1)
> 
>   xlabel(r"$\[$")
>   xlabel( "$\[$")    no error, but displays a star symbol
> 
> In the last two cases I got a warning
> 
> mathtext.py:722: MathTextWarning: Unrecognized symbol '\['. Substituting 
> with a dummy symbol.
>   % sym.encode('ascii', 'backslashreplace'), MathTextWarning)

Cheers,
Mike

>> Matthias Michler wrote:
>>> Hello list,
>>>
>>> the little example below leads to an error on my system (output is 
>>> attached).
>>> I used this some time ago and it worked. Now I'm using the release 
>>> 0.91.2.
>>> Is there a reason to use rectangular brackets not in mathtext?
>>> (same problem occur with '{' for me.)
>>>
>>> best regards and thanks in advance for any help,
>>> Matthias
>>> ------------------------------------------------------------------------------------------------- 
>>>
>>> import matplotlib.pyplot as mpl_pp
>>> mpl_pp.axes()
>>> mpl_pp.xlabel("$[$")
>>> mpl_pp.show()
>>>
>>>
>>> ------------------------------------------------------------------------
>>>
>>> ------------------------------------------------------------------------- 
>>>
>>> Check out the new SourceForge.net Marketplace.
>>> It's the best place to buy or sell services for
>>> just about anything Open Source.
>>> http://ad.doubleclick.net/clk;164216239;13503038;w?http://sf.net/marketplace 
>>>
>>>
>>>
>>> ------------------------------------------------------------------------
>>>
>>> _______________________________________________
>>> Matplotlib-users mailing list
>>> Mat...@li...
>>> https://lists.sourceforge.net/lists/listinfo/matplotlib-users
>>
> 
> 

-- 
Michael Droettboom
Science Software Branch
Operations and Engineering Division
Space Telescope Science Institute
Operated by AURA for NASA