matplotlib-devel Mailing List for matplotlib

Sorry for the multiple mailings.
in makers.py I request to change
 def _set_custom_marker(self, path):
 verts = path.vertices
 rescale = max(np.max(np.abs(verts[:,0])),
np.max(np.abs(verts[:,1])))
 self._transform = Affine2D().scale(1.0 / rescale)
 self._path = path
to
 def _set_custom_marker(self, path):
 verts = path.vertices
 rescale = np.max(np.sqrt(np.square(verts[:,0]) +
np.square(verts[:,1])))
 self._transform = Affine2D().scale(1.0 / rescale)
 self._path = path
such that the symbol *radius* is normalized to 1.0
This way my previous example give better results if the symbol is rotated:
import matplotlib.path as path
from matplotlib.transforms import Affine2D
# define codes
P = path.Path
Pm = P.MOVETO
Pl = P.LINETO
Pc = P.CLOSEPOLY
c = [Pm] + [Pl]*3 + [Pc]
cx=c*2
# define basic path
r=np.array(((-1.,-1),(1.,-1),(1.,1.),(-1,1.),(-1,-1)))
# we add second closed path of half size but reverse parity
rh=0.5*r[::-1]
rx = np.vstack((r,rh))
p = path.Path(rx,codes=cx)
x = np.linspace(0,1,10)**2
plot(x,c='r',marker=p,ms=10)
pr = p.transformed(Affine2D().rotate_deg(45.))
plot(x,c='r',marker=pr,ms=10)
show()
I think this is how it is "meant" to be, but maybe you have to add a
parameter to allow people recover the current behavior in that case.
-Alexander
====
I just like round cows better than square cows.

in makers.py I request to change
 def _set_custom_marker(self, path):
 verts = path.vertices
 rescale = max(np.max(np.abs(verts[:,0])), 
np.max(np.abs(verts[:,1])))
 self._transform = Affine2D().scale(1.0 / rescale)
 self._path = path
to
 def _set_custom_marker(self, path):
 verts = path.vertices
 rescale = np.max(np.sqrt(np.square(verts[:,0]) + 
np.square(verts[:,1])))
 self._transform = Affine2D().scale(1.0 / rescale)
 self._path = path
such that the symbol *radius* is normalized to 1.0
This way my previous example give better results if the symbol is rotated:
import matplotlib.path as path
from matplotlib.transforms import Affine2D
# define codes
P = path.Path
Pm = P.MOVETO
Pl = P.LINETO
Pc = P.CLOSEPOLY
c = [Pm] + [Pl]*3 + [Pc]
cx=c*2
# define basic path
r=np.array(((-1.,-1),(1.,-1),(1.,1.),(-1,1.),(-1,-1)))
# we add second closed path of half size but reverse parity
rh=0.5*r[::-1]
rx = np.vstack((r,rh))
p = path.Path(rx,codes=cx)
x = np.linspace(0,1,10)**2
plot(x,c='r',marker=p,ms=10)
pr = p.transformed(Affine2D().rotate_deg(45.))
plot(x,c='r',marker=pr,ms=10)
show()
I think this is how it is "meant" to be, but maybe you have to add a 
parameter to allow people recover the current behavior in that case.
-Alexander
====
I just like round cows better than square cows.

In [1]: matplotlib.__version__
Out[1]: '1.2.x'
~/matplotlib/lib/matplotlib>diff markers.py_broken markers.py
190c190
< path = Path(verts)
---
 > path = Path(self._marker)
PS - I tried to log into
https://github.com/matplotlib/matplotlib/issues
using my mailing list password to create a bug report, but it would not 
accept it, so you get it this way.
DOCUMENTATION NOTES
1) in the table for marker vertices it states
http://matplotlib.sourceforge.net/api/artist_api.html#matplotlib.lines.Line2D.set_marker
verts	a list of (x, y) pairs in range (0, 1)
it really should be just normalized or abs(1), (0,0) being center, and 
hence the (x,y) values should be in the range (-1,+1). Would be good to 
add an example
x=np.linspace(0,1,10)**2
plot(x,c='r',marker=((-1.,-1),(1.,-1),(1.,1.),(-1,1.),(-1,-1)),ms=10)
2) the source also support to just provide a path as a marker, which (a) 
is cool, and (b) seemed natural as internal many things are done a 
paths, and even complies paths are generated from the $...$ syntax math. 
 In any case, this should be added to the documentation for allowed markers
path	a matplotlib.path.Path object
import matplotlib.path as path
x = np.linspace(0,1,10)**2
p = path.Path(((-1.,-1),(1.,-1),(1.,1.),(-1,1.),(-1,-1)))
plot(x,c='r',marker=p,ms=10)
or a cool example that you may want tot add to the library...
import matplotlib.path as path
# define codes
P = path.Path
Pm = P.MOVETO
Pl = P.LINETO
Pc = P.CLOSEPOLY
c = [Pm] + [Pl]*3 + [Pc]
cx=c*2
# define basic path
r=np.array(((-1.,-1),(1.,-1),(1.,1.),(-1,1.),(-1,-1)))
# we add second closed path of half size but reverse parity
rh=0.5*r[::-1]
rx = np.vstack((r,rh))
p = path.Path(rx,codes=cx)
x = np.linspace(0,1,10)**2
plot(x,c='r',marker=p,ms=10)
PS - I guess I need to figure out how to do such updates w/o requesting 
action from the lest eventually.
Just to emphasize (2a): COOL!!!
Wishlist:
Can we add a "transform" parameter to overwrite self._transform?
I suppose this would have to go many places.
"set_marker_transform"
Maybe add to MarkerStyle
from transforms import Transform
def self.set_transform(self, transform = IdentityTransform()):
 assert isinstance(x, Transform)					
 self._transfrom = transfrom()
Maybe less fancy, and better for starters, to add an angle
"set_marker_rotation(angle)"
using
Affine2D().rotate_deg(angle)
-Alexander