Hi, I think I've found a bug. Basically I'm trying to use vertex_size with graph_draw() using a GraphView, but it only seems to work with the original graph.

import graph_tool.all as gt
from numpy.random import randint, random
from itertools import izip

N = 50
g = gt.Graph()

g.add_vertex(N)
# insert some random links
for s,t in izip(randint(0, N, N), randint(0, N, N)):
    g.add_edge(g.vertex(s), g.vertex(t))

vsize = g.new_vertex_property('float')
vsize.a = random(N)**2
vsize = gt.prop_to_size(vsize)
vsize.a *= 10

# this works
gt.graph_draw(g, vertex_size=vsize)

gv = gt.GraphView(g, vfilt=lambda v:v.out_degree()>1)
# this doesn't
gt.graph_draw(gv, vertex_size=vsize)

The traceback is:

/usr/lib/python2.7/dist-packages/graph_tool/draw/cairo_draw.pyc in get_bb(g, pos, size, pen_width, size_scale, text, font_family, font_size, cr)
   1279     x_range = [pos_x.fa.min(), pos_x.fa.max()]
   1280     y_range = [pos_y.fa.min(), pos_y.fa.max()]
-> 1281     x_delta = [x_range[0] - (pos_x.fa - delta).min(),
   1282                (pos_x.fa + delta).max() - x_range[1]]
   1283     y_delta = [y_range[0] - (pos_y.fa - delta).min(),

ValueError: operands could not be broadcast together with shapes (13,) (50,) 

Thanks,
-Rick