matplotlib-devel Mailing List for matplotlib

John Hunter wrote:
>Quick comments. I'd like to continue using the matplotlib naming
>convention (UpperCase) for class names, rather than underscore
>separated
> 
>
Okay, I started to convert the names. I haven't yet done this for the 
more internal functions (i.e. things like lines_properties).
>class trait_color(Trait):
>
>also, 
>
>I don't think we should use the name Trait or HasTrait, since that
>will confuse people into thinking we are using enthought traits
>(Property and HasProperty ?) 
> 
>
Fair enough. I changed it to HasProperties and Property.. It's a little 
verbose, but I guess it won't be used very much outside of the file.
>Finally, another feature I would like to be able to support, which
>won't be hard, is to enable the use of an RC class or something like
>it in Artist constructors
>
>Here is what we currently have
>
> def __init__(self, xdata, ydata,
> linewidth = None, # default to rc
> linestyle = None, # default to rc
> color = None, # default to rc
>...snip..
> ):
>
>This overloads None which leads to strange usages like
>linestyle='None' to turn off lines (note the quotes). I would rather
>do something like
>
>
> def __init__(self, xdata, ydata,
> linewidth = RC('lines.linewidth'),
> linestyle = RC('lines.linestyle')
>...snip...
> ):
> if isinstance(linewidth, RC): linewidth=linewidth()
>
>Note that this is different than
>
> def __init__(self, xdata, ydata,
> linewidth = rc.lines.linewidth,
> linestyle = rc.lines.linestyle,
>...snip...
> ):
> 
>
Okay, I changed the HasProperties class to include a 'get()' function as 
well. This allows for:
rc.get('lines.linewidth') ==> a Property-subclass instance
The only problem with this, is that this might not be what the person is 
expecting. I could easily change the get function to instead return the 
value of the Property, but there are uses for getting the actual 
Property back as well.. Of course one can override the __float__, 
__int__, etc. methods, but this still requires explicit conversion, thus 
the user still has to know something about the internals.
My current solution was to add a function 'getValue', which is the same 
as get, but returns just the value. This could also very easily be 
wrapped up in a function:
def RC(name): return rc.getValue(name)
>The syntax above is not the point. What I want to emphasize is that I
>want a self documenting way of saying this parameter defaults to an rc
>param, and that param should be evaluated *at init time*. If you can
>do it with the second syntax, that looks better, but if I read your
>code correctly, something like rc.lines.linewidth evaluates to a float
>at module load time and so cannot be used as a sentinel at module init
>time. Is this correct?
> 
>
Nope, it keeps as a property, and thus has sentinel-capabilities.
>In any case, it looks very promising. Two final comments. Like
>Fernando, I'm not too concerned about being able to parse existing rc
>files. It's a minor burden to require people simply to take the new
>format and customize it. Also, do you need to extend the fontsize
>train to support fontsizes in points, eg 12.0 ?
> 
>
Currently it accepts either a float or one of the keywords. It should be 
fairly easy to extend it to also use the syntax '12.4pt' or '12in' (i.e. 
LaTeX style -- of course someone would have to write a conversion 
function..)
>Well if it already parses existing rc, no reason to kill it.
> 
>
As long as we keep the 1-to-1 mapping, it's easy enough to do. It's the 
same code (plus reading in the file) what is done for rc.get('x.y.z')
Abe

Hello John,
On Sun, Feb 06, 2005 at 11:49:36AM -0600, John Hunter wrote:
> Last time Paul looked at this (when he implemented freetype fonts for
> PS mathtext), he came to the conclusion that it was not possible to
> extract individual glyphs fro ps file, and had to resort to dumping in
> the entire file. I don't believe this is the case.
I agree, there is no reason why we should not be able to
create a font with only selected glyphs.
> Any takers?
I always meant to take a look at that, but momentarily I am a little
bit short of time. So if anybody else could implement this, this
would be great! Otherwise I might be able to have a look during next
weekend.
All the best,
Jochen
--=20
http://seehuhn.de/