class ContourLabeler:
def __init__(self, ax):
self.ax = ax
def clabel(self, *args, **kwargs):
"""
CLABEL(*args, **kwargs)
Function signatures
CLABEL(C) - plots contour labels,
C is the output of contour or a list of contours
CLABEL(C,V) - creates labels only for those contours, given in
a list V
CLABEL(C, **kwargs) - keyword args are explained below:
* fontsize = None: as described in http://matplotlib.sf.net/fonts.html
* colors = None:
- a tuple of matplotlib color args (string, float, rgb, etc),
different labels will be plotted in different colors in the order
specified
- one string color, e.g. colors = 'r' or colors = 'red', all labels
will be plotted in this color
- if colors == None, the color of each label matches the color
of the corresponding contour
* inline = 0: controls whether the underlying contour is removed
(inline = 1) or not
* fmt = '%1.3f': a format string for the label
"""
# todo, factor this out to a separate class and don't use hidden coll attrs
if not self.ax.ishold(): self.ax.cla()
fontsize = kwargs.get('fontsize', None)
inline = kwargs.get('inline', 0)
fmt = kwargs.get('fmt', '%1.3f')
colors = kwargs.get('colors', None)
if len(args) == 1:
contours = args[0]
levels = [con._label for con in contours]
elif len(args) == 2:
contours = args[0]
levels = args[1]
else:
raise TypeError("Illegal arguments to clabel, see help(clabel)")
self.fp = FontProperties()
if fontsize == None:
font_size = int(self.fp.get_size_in_points())
else:
if type(fontsize) not in [int, float, str]:
raise TypeError("Font size must be an integer number.")
else:
if type(fontsize) == str:
font_size = int(self.fp.get_size_in_points())
else:
self.fp.set_size(fontsize)
font_size = fontsize
fslist = [font_size] * len(levels)
if colors == None:
colors = [c._colors[0] for c in contours]
else:
colors = colors * len(contours)
if inline not in [0, 1]:
raise TypeError("inline must be 0 or 1")
self.cl = []
self.cl_xy = []
# we have a list of contours and each contour has a list of
# segments. We want changes in the contour color to be
# reflected in changes in the label color. This is a good use
# for traits observers, but in the interim, until traits are
# utilized, we'll create a dict mapping i,j to text instances.
# i is the contour level index, j is the sement index
self.labeld = {}
if inline == 1:
self.inline_labels(levels, contours, colors, fslist, fmt)
else:
self.labels(levels, contours, colors, fslist, fmt)
for label in self.cl:
self.ax.add_artist(label)
ret = silent_list('Text', self.cl)
ret.mappable = getattr(contours, 'mappable', None)
# support colormapping for label
if ret.mappable is not None:
ret.mappable.labeld = self.labeld
return ret
def print_label(self, linecontour, labelwidth):
"if contours are too short, don't plot a label"
lcsize = len(linecontour)
if lcsize > 10 * labelwidth:
return 1
xmax = amax(array(linecontour)[:, 0])
xmin = amin(array(linecontour)[:, 0])
ymax = amax(array(linecontour)[:, 1])
ymin = amin(array(linecontour)[:, 1])
lw = labelwidth
if (xmax - xmin) > 1.2 * lw or (ymax - ymin) > 1.2 * lw:
return 1
else:
return 0
def too_close(self, x, y, lw):
"if there's a label already nearby, find a better place"
if self.cl_xy != []:
dist = [
sqrt((x - loc[0])**2 + (y - loc[1])**2) for loc in self.cl_xy
]
for d in dist:
if d < 1.2 * lw:
return 1
else:
return 0
else:
return 0
def get_label_coords(self, distances, XX, YY, ysize, lw):
""" labels are ploted at a location with the smallest
dispersion of the contour from a straight line
unless there's another label nearby, in which case
the second best place on the contour is picked up
if there's no good place a label isplotted at the
beginning of the contour
"""
hysize = int(ysize / 2)
adist = argsort(distances)
for ind in adist:
x, y = XX[ind][hysize], YY[ind][hysize]
if self.too_close(x, y, lw):
continue
else:
self.cl_xy.append((x, y))
return x, y, ind
ind = adist[0]
x, y = XX[ind][hysize], YY[ind][hysize]
self.cl_xy.append((x, y))
return x, y, ind
def get_label_width(self, lev, fmt, fsize):
"get the width of the label in points"
if is_string_like(lev):
lw = (len(lev)) * fsize
else:
lw = (len(fmt % lev)) * fsize
return lw
def set_label_props(self, label, text, color):
"set the label properties - color, fontsize, text"
label.set_text(text)
label.set_color(color)
label.set_fontproperties(self.fp)
label.set_clip_box(self.ax.bbox)
def get_text(self, lev, fmt):
"get the text of the label"
if is_string_like(lev):
return lev
else:
return fmt % lev
def break_linecontour(self, linecontour, rot, labelwidth, ind):
"break a contour in two contours at the location of the label"
lcsize = len(linecontour)
hlw = int(labelwidth / 2)
#length of label in screen coords
ylabel = abs(hlw * sin(rot * pi / 180))
xlabel = abs(hlw * cos(rot * pi / 180))
trans = self.ax.transData
slc = trans.seq_xy_tups(linecontour)
x, y = slc[ind]
xx = array(slc)[:, 0].copy()
yy = array(slc)[:, 1].copy()
#indices which are under the label
inds = nonzero(((xx < x + xlabel) & (xx > x - xlabel))
& ((yy < y + ylabel) & (yy > y - ylabel)))
if len(inds) > 0:
#if the label happens to be over the beginning of the
#contour, the entire contour is removed, i.e.
#indices to be removed are
#inds= [0,1,2,3,305,306,307]
#should rewrite this in a better way
linds = nonzero(inds[1:] - inds[:-1] != 1)
if inds[0] == 0 and len(linds) != 0:
ii = inds[linds[0]]
lc1 = linecontour[ii + 1:inds[ii + 1]]
lc2 = []
else:
lc1 = linecontour[:inds[0]]
lc2 = linecontour[inds[-1] + 1:]
else:
lc1 = linecontour[:ind]
lc2 = linecontour[ind + 1:]
if rot < 0:
new_x1, new_y1 = x - xlabel, y + ylabel
new_x2, new_y2 = x + xlabel, y - ylabel
else:
new_x1, new_y1 = x - xlabel, y - ylabel
new_x2, new_y2 = x + xlabel, y + ylabel
new_x1d, new_y1d = trans.inverse_xy_tup((new_x1, new_y1))
new_x2d, new_y2d = trans.inverse_xy_tup((new_x2, new_y2))
if rot > 0:
if len(lc1) > 0 and (lc1[-1][0] <= new_x1d) and (lc1[-1][1] <=
new_y1d):
lc1.append((new_x1d, new_y1d))
if len(lc2) > 0 and (lc2[0][0] >= new_x2d) and (lc2[0][1] >=
new_y2d):
lc2.insert(0, (new_x2d, new_y2d))
else:
if len(lc1) > 0 and ((lc1[-1][0] <= new_x1d) and
(lc1[-1][1] >= new_y1d)):
lc1.append((new_x1d, new_y1d))
if len(lc2) > 0 and ((lc2[0][0] >= new_x2d) and
(lc2[0][1] <= new_y2d)):
lc2.insert(0, (new_x2d, new_y2d))
return [lc1, lc2]
def locate_label(self, linecontour, labelwidth):
"""find a good place to plot a label (relatively flat
part of the contour) and the angle of rotation for the
text object
"""
nsize = len(linecontour)
if labelwidth > 1:
xsize = int(ceil(nsize / labelwidth))
else:
xsize = 1
if xsize == 1:
ysize = nsize
else:
ysize = labelwidth
XX = resize(array(linecontour)[:, 0], (xsize, ysize))
YY = resize(array(linecontour)[:, 1], (xsize, ysize))
yfirst = YY[:, 0]
ylast = YY[:, -1]
xfirst = XX[:, 0]
xlast = XX[:, -1]
s = (reshape(yfirst,
(xsize, 1)) - YY) * (reshape(xlast, (xsize, 1)) - reshape(
xfirst,
(xsize, 1))) - (reshape(xfirst, (xsize, 1)) - XX) * (
reshape(ylast,
(xsize, 1)) - reshape(yfirst, (xsize, 1)))
L = sqrt((xlast - xfirst)**2 + (ylast - yfirst)**2)
dist = add.reduce(([(abs(s)[i] / L[i]) for i in range(xsize)]), -1)
x, y, ind = self.get_label_coords(dist, XX, YY, ysize, labelwidth)
angle = arctan2(ylast - yfirst, xlast - xfirst)
rotation = angle[ind] * 180 / pi
if rotation > 90:
rotation = rotation - 180
if rotation < -90:
rotation = 180 + rotation
dind = list(linecontour).index((x, y))
return x, y, rotation, dind
def inline_labels(self, levels, contours, colors, fslist, fmt):
trans = self.ax.transData
contourNum = 0
for lev, con, color, fsize in zip(levels, contours, colors, fslist):
toremove = []
toadd = []
lw = self.get_label_width(lev, fmt, fsize)
for segNum, linecontour in enumerate(con._segments):
key = contourNum, segNum
# for closed contours add one more point to
# avoid division by zero
if linecontour[0] == linecontour[-1]:
linecontour.append(linecontour[1])
# transfer all data points to screen coordinates
slc = trans.seq_xy_tups(linecontour)
if self.print_label(slc, lw):
x, y, rotation, ind = self.locate_label(slc, lw)
# transfer the location of the label back to
# data coordinates
dx, dy = trans.inverse_xy_tup((x, y))
t = Text(dx,
dy,
rotation=rotation,
horizontalalignment='center',
verticalalignment='center')
self.labeld[key] = t
text = self.get_text(lev, fmt)
self.set_label_props(t, text, color)
self.cl.append(t)
new = self.break_linecontour(linecontour, rotation, lw,
ind)
for c in new:
toadd.append(c)
toremove.append(linecontour)
for c in toremove:
con._segments.remove(c)
for c in toadd:
con._segments.append(c)
contourNum += 1
def labels(self, levels, contours, colors, fslist, fmt):
trans = self.ax.transData
for lev, con, color, fsize in zip(levels, contours, colors, fslist):
lw = self.get_label_width(lev, fmt, fsize)
for linecontour in con._segments:
# for closed contours add one more point
if linecontour[0] == linecontour[-1]:
linecontour.append(linecontour[1])
# transfer all data points to screen coordinates
slc = trans.seq_xy_tups(linecontour)
if self.print_label(slc, lw):
x, y, rotation, ind = self.locate_label(slc, lw)
# transfer the location of the label back into
# data coordinates
dx, dy = trans.inverse_xy_tup((x, y))
t = Text(dx,
dy,
rotation=rotation,
horizontalalignment='center',
verticalalignment='center')
text = self.get_text(lev, fmt)
self.set_label_props(t, text, color)
self.cl.append(t)
else:
pass
class ContourLabeler:
'''Mixin to provide labelling capability to ContourSet'''
def clabel(self, *args, **kwargs):
"""
clabel(CS, **kwargs) - add labels to line contours in CS,
where CS is a ContourSet object returned by contour.
clabel(CS, V, **kwargs) - only label contours listed in V
keyword arguments:
* fontsize = None: as described in http://matplotlib.sf.net/fonts.html
* colors = None:
- a tuple of matplotlib color args (string, float, rgb, etc),
different labels will be plotted in different colors in the order
specified
- one string color, e.g. colors = 'r' or colors = 'red', all labels
will be plotted in this color
- if colors == None, the color of each label matches the color
of the corresponding contour
* inline = True: controls whether the underlying contour is removed
(inline = True) or not (False)
* fmt = '%1.3f': a format string for the label
"""
fontsize = kwargs.get('fontsize', None)
inline = kwargs.get('inline', 1)
self.fmt = kwargs.get('fmt', '%1.3f')
colors = kwargs.get('colors', None)
if len(args) == 0:
levels = self.levels
indices = range(len(self.levels))
elif len(args) == 1:
levlabs = list(args[0])
indices, levels = [], []
for i, lev in enumerate(self.levels):
if lev in levlabs:
indices.append(i)
levels.append(lev)
if len(levels) < len(levlabs):
msg = "Specified levels " + str(levlabs)
msg += "\n don't match available levels "
msg += str(self.levels)
raise ValueError(msg)
else:
raise TypeError("Illegal arguments to clabel, see help(clabel)")
self.label_levels = levels
self.label_indices = indices
self.fp = FontProperties()
if fontsize == None:
font_size = int(self.fp.get_size_in_points())
else:
if type(fontsize) not in [int, float, str]:
raise TypeError("Font size must be an integer number.")
# Can't it be floating point, as indicated in line above?
else:
if type(fontsize) == str:
font_size = int(self.fp.get_size_in_points())
else:
self.fp.set_size(fontsize)
font_size = fontsize
self.fslist = [font_size] * len(levels)
if colors == None:
self.label_mappable = self
self.label_cvalues = take(self.cvalues, self.label_indices)
else:
cmap = ListedColormap(colors, N=len(self.label_levels))
self.label_cvalues = range(len(self.label_levels))
self.label_mappable = ScalarMappable(cmap=cmap, norm=no_norm())
#self.cl = [] # Initialized in ContourSet.__init__
#self.cl_cvalues = [] # same
self.cl_xy = []
self.labels(inline)
for label in self.cl:
self.ax.add_artist(label)
self.label_list = silent_list('Text', self.cl)
return self.label_list
def print_label(self, linecontour, labelwidth):
"if contours are too short, don't plot a label"
lcsize = len(linecontour)
if lcsize > 10 * labelwidth:
return 1
xmax = amax(array(linecontour)[:, 0])
xmin = amin(array(linecontour)[:, 0])
ymax = amax(array(linecontour)[:, 1])
ymin = amin(array(linecontour)[:, 1])
lw = labelwidth
if (xmax - xmin) > 1.2 * lw or (ymax - ymin) > 1.2 * lw:
return 1
else:
return 0
def too_close(self, x, y, lw):
"if there's a label already nearby, find a better place"
if self.cl_xy != []:
dist = [
sqrt((x - loc[0])**2 + (y - loc[1])**2) for loc in self.cl_xy
]
for d in dist:
if d < 1.2 * lw:
return 1
else:
return 0
else:
return 0
def get_label_coords(self, distances, XX, YY, ysize, lw):
""" labels are ploted at a location with the smallest
dispersion of the contour from a straight line
unless there's another label nearby, in which case
the second best place on the contour is picked up
if there's no good place a label isplotted at the
beginning of the contour
"""
hysize = int(ysize / 2)
adist = argsort(distances)
for ind in adist:
x, y = XX[ind][hysize], YY[ind][hysize]
if self.too_close(x, y, lw):
continue
else:
self.cl_xy.append((x, y))
return x, y, ind
ind = adist[0]
x, y = XX[ind][hysize], YY[ind][hysize]
self.cl_xy.append((x, y))
return x, y, ind
def get_label_width(self, lev, fmt, fsize):
"get the width of the label in points"
if is_string_like(lev):
lw = (len(lev)) * fsize
else:
lw = (len(fmt % lev)) * fsize
return lw
def set_label_props(self, label, text, color):
"set the label properties - color, fontsize, text"
label.set_text(text)
label.set_color(color)
label.set_fontproperties(self.fp)
label.set_clip_box(self.ax.bbox)
def get_text(self, lev, fmt):
"get the text of the label"
if is_string_like(lev):
return lev
else:
return fmt % lev
def break_linecontour(self, linecontour, rot, labelwidth, ind):
"break a contour in two contours at the location of the label"
lcsize = len(linecontour)
hlw = int(labelwidth / 2)
#length of label in screen coords
ylabel = abs(hlw * sin(rot * pi / 180))
xlabel = abs(hlw * cos(rot * pi / 180))
trans = self.ax.transData
slc = trans.seq_xy_tups(linecontour)
x, y = slc[ind]
xx = asarray(slc)[:, 0].copy()
yy = asarray(slc)[:, 1].copy()
#indices which are under the label
inds = nonzero(((xx < x + xlabel) & (xx > x - xlabel))
& ((yy < y + ylabel) & (yy > y - ylabel)))
if len(inds) > 0:
#if the label happens to be over the beginning of the
#contour, the entire contour is removed, i.e.
#indices to be removed are
#inds= [0,1,2,3,305,306,307]
#should rewrite this in a better way
linds = nonzero(inds[1:] - inds[:-1] != 1)
if inds[0] == 0 and len(linds) != 0:
ii = inds[linds[0]]
lc1 = linecontour[ii + 1:inds[ii + 1]]
lc2 = []
else:
lc1 = linecontour[:inds[0]]
lc2 = linecontour[inds[-1] + 1:]
else:
lc1 = linecontour[:ind]
lc2 = linecontour[ind + 1:]
if rot < 0:
new_x1, new_y1 = x - xlabel, y + ylabel
new_x2, new_y2 = x + xlabel, y - ylabel
else:
new_x1, new_y1 = x - xlabel, y - ylabel
new_x2, new_y2 = x + xlabel, y + ylabel
new_x1d, new_y1d = trans.inverse_xy_tup((new_x1, new_y1))
new_x2d, new_y2d = trans.inverse_xy_tup((new_x2, new_y2))
new_xy1 = array(((new_x1d, new_y1d), ))
new_xy2 = array(((new_x2d, new_y2d), ))
if rot > 0:
if (len(lc1) > 0 and (lc1[-1][0] <= new_x1d)
and (lc1[-1][1] <= new_y1d)):
lc1 = concatenate((lc1, new_xy1))
#lc1.append((new_x1d, new_y1d))
if (len(lc2) > 0 and (lc2[0][0] >= new_x2d)
and (lc2[0][1] >= new_y2d)):
lc2 = concatenate((new_xy2, lc2))
#lc2.insert(0, (new_x2d, new_y2d))
else:
if (len(lc1) > 0
and ((lc1[-1][0] <= new_x1d) and (lc1[-1][1] >= new_y1d))):
lc1 = concatenate((lc1, new_xy1))
#lc1.append((new_x1d, new_y1d))
if (len(lc2) > 0
and ((lc2[0][0] >= new_x2d) and (lc2[0][1] <= new_y2d))):
lc2 = concatenate((new_xy2, lc2))
#lc2.insert(0, (new_x2d, new_y2d))
return [lc1, lc2]
def locate_label(self, linecontour, labelwidth):
"""find a good place to plot a label (relatively flat
part of the contour) and the angle of rotation for the
text object
"""
nsize = len(linecontour)
if labelwidth > 1:
xsize = int(ceil(nsize / labelwidth))
else:
xsize = 1
if xsize == 1:
ysize = nsize
else:
ysize = labelwidth
XX = resize(asarray(linecontour)[:, 0], (xsize, ysize))
YY = resize(asarray(linecontour)[:, 1], (xsize, ysize))
yfirst = YY[:, 0]
ylast = YY[:, -1]
xfirst = XX[:, 0]
xlast = XX[:, -1]
s = ((reshape(yfirst, (xsize, 1)) - YY) *
(reshape(xlast, (xsize, 1)) - reshape(xfirst, (xsize, 1))) -
(reshape(xfirst, (xsize, 1)) - XX) *
(reshape(ylast, (xsize, 1)) - reshape(yfirst, (xsize, 1))))
L = sqrt((xlast - xfirst)**2 + (ylast - yfirst)**2)
dist = add.reduce(([(abs(s)[i] / L[i]) for i in range(xsize)]), -1)
x, y, ind = self.get_label_coords(dist, XX, YY, ysize, labelwidth)
#print 'ind, x, y', ind, x, y
angle = arctan2(ylast - yfirst, xlast - xfirst)
rotation = angle[ind] * 180 / pi
if rotation > 90:
rotation = rotation - 180
if rotation < -90:
rotation = 180 + rotation
# There must be a more efficient way...
lc = [tuple(l) for l in linecontour]
dind = lc.index((x, y))
#print 'dind', dind
#dind = list(linecontour).index((x,y))
return x, y, rotation, dind
def labels(self, inline):
levels = self.label_levels
fslist = self.fslist
trans = self.ax.transData
colors = self.label_mappable.to_rgba(self.label_cvalues)
fmt = self.fmt
for icon, lev, color, cvalue, fsize in zip(self.label_indices,
self.label_levels, colors,
self.label_cvalues, fslist):
con = self.collections[icon]
lw = self.get_label_width(lev, fmt, fsize)
additions = []
for segNum, linecontour in enumerate(con._segments):
# for closed contours add one more point to
# avoid division by zero
if all(linecontour[0] == linecontour[-1]):
linecontour = concatenate(
(linecontour, linecontour[1][newaxis, :]))
#linecontour.append(linecontour[1])
# transfer all data points to screen coordinates
slc = trans.seq_xy_tups(linecontour)
if self.print_label(slc, lw):
x, y, rotation, ind = self.locate_label(slc, lw)
# transfer the location of the label back to
# data coordinates
dx, dy = trans.inverse_xy_tup((x, y))
t = Text(dx,
dy,
rotation=rotation,
horizontalalignment='center',
verticalalignment='center')
text = self.get_text(lev, fmt)
self.set_label_props(t, text, color)
self.cl.append(t)
self.cl_cvalues.append(cvalue)
if inline:
new = self.break_linecontour(linecontour, rotation, lw,
ind)
con._segments[segNum] = new[0]
additions.append(new[1])
con._segments.extend(additions)
class ContourLabeler:
'''Mixin to provide labelling capability to ContourSet'''
def clabel(self, *args, **kwargs):
"""
clabel(CS, **kwargs) - add labels to line contours in CS,
where CS is a ContourSet object returned by contour.
clabel(CS, V, **kwargs) - only label contours listed in V
keyword arguments:
* fontsize = None: as described in http://matplotlib.sf.net/fonts.html
* colors = None:
- a tuple of matplotlib color args (string, float, rgb, etc),
different labels will be plotted in different colors in the order
specified
- one string color, e.g. colors = 'r' or colors = 'red', all labels
will be plotted in this color
- if colors == None, the color of each label matches the color
of the corresponding contour
* inline = True: controls whether the underlying contour is removed
(inline = True) or not (False)
* fmt = '%1.3f': a format string for the label
"""
fontsize = kwargs.get('fontsize', None)
inline = kwargs.get('inline', 1)
self.fmt = kwargs.get('fmt', '%1.3f')
colors = kwargs.get('colors', None)
if len(args) == 0:
levels = self.levels
indices = range(len(self.levels))
elif len(args) == 1:
levlabs = list(args[0])
indices, levels = [], []
for i, lev in enumerate(self.levels):
if lev in levlabs:
indices.append(i)
levels.append(lev)
if len(levels) < len(levlabs):
msg = "Specified levels " + str(levlabs)
msg += "\n don't match available levels "
msg += str(self.levels)
raise ValueError(msg)
else:
raise TypeError("Illegal arguments to clabel, see help(clabel)")
self.label_levels = levels
self.label_indices = indices
self.fp = FontProperties()
if fontsize == None:
font_size = int(self.fp.get_size_in_points())
else:
if type(fontsize) not in [int, float, str]:
raise TypeError("Font size must be an integer number.")
# Can't it be floating point, as indicated in line above?
else:
if type(fontsize) == str:
font_size = int(self.fp.get_size_in_points())
else:
self.fp.set_size(fontsize)
font_size = fontsize
self.fslist = [font_size] * len(levels)
if colors == None:
self.label_mappable = self
self.label_cvalues = take(self.cvalues, self.label_indices)
else:
cmap = ListedColormap(colors, N=len(self.label_levels))
self.label_cvalues = range(len(self.label_levels))
self.label_mappable = ScalarMappable(cmap = cmap,
norm = no_norm())
#self.cl = [] # Initialized in ContourSet.__init__
#self.cl_cvalues = [] # same
self.cl_xy = []
self.labels(inline)
for label in self.cl:
self.ax.add_artist(label)
self.label_list = silent_list('Text', self.cl)
return self.label_list
def print_label(self, linecontour,labelwidth):
"if contours are too short, don't plot a label"
lcsize = len(linecontour)
if lcsize > 10 * labelwidth:
return 1
xmax = amax(array(linecontour)[:,0])
xmin = amin(array(linecontour)[:,0])
ymax = amax(array(linecontour)[:,1])
ymin = amin(array(linecontour)[:,1])
lw = labelwidth
if (xmax - xmin) > 1.2* lw or (ymax - ymin) > 1.2 * lw:
return 1
else:
return 0
def too_close(self, x,y, lw):
"if there's a label already nearby, find a better place"
if self.cl_xy != []:
dist = [sqrt((x-loc[0]) ** 2 + (y-loc[1]) ** 2)
for loc in self.cl_xy]
for d in dist:
if d < 1.2*lw:
return 1
else: return 0
else: return 0
def get_label_coords(self, distances, XX, YY, ysize, lw):
""" labels are ploted at a location with the smallest
dispersion of the contour from a straight line
unless there's another label nearby, in which case
the second best place on the contour is picked up
if there's no good place a label isplotted at the
beginning of the contour
"""
hysize = int(ysize/2)
adist = argsort(distances)
for ind in adist:
x, y = XX[ind][hysize], YY[ind][hysize]
if self.too_close(x,y, lw):
continue
else:
self.cl_xy.append((x,y))
return x,y, ind
ind = adist[0]
x, y = XX[ind][hysize], YY[ind][hysize]
self.cl_xy.append((x,y))
return x,y, ind
def get_label_width(self, lev, fmt, fsize):
"get the width of the label in points"
if is_string_like(lev):
lw = (len(lev)) * fsize
else:
lw = (len(fmt%lev)) * fsize
return lw
def set_label_props(self, label, text, color):
"set the label properties - color, fontsize, text"
label.set_text(text)
label.set_color(color)
label.set_fontproperties(self.fp)
label.set_clip_box(self.ax.bbox)
def get_text(self, lev, fmt):
"get the text of the label"
if is_string_like(lev):
return lev
else:
return fmt%lev
def break_linecontour(self, linecontour, rot, labelwidth, ind):
"break a contour in two contours at the location of the label"
lcsize = len(linecontour)
hlw = int(labelwidth/2)
#length of label in screen coords
ylabel = abs(hlw * sin(rot*pi/180))
xlabel = abs(hlw * cos(rot*pi/180))
trans = self.ax.transData
slc = trans.seq_xy_tups(linecontour)
x,y = slc[ind]
xx= array(slc)[:,0].copy()
yy=array(slc)[:,1].copy()
#indices which are under the label
inds=nonzero(((xx < x+xlabel) & (xx > x-xlabel)) &
((yy < y+ylabel) & (yy > y-ylabel)))
if len(inds) >0:
#if the label happens to be over the beginning of the
#contour, the entire contour is removed, i.e.
#indices to be removed are
#inds= [0,1,2,3,305,306,307]
#should rewrite this in a better way
linds = nonzero(inds[1:]- inds[:-1] != 1)
if inds[0] == 0 and len(linds) != 0:
ii = inds[linds[0]]
lc1 =linecontour[ii+1:inds[ii+1]]
lc2 = []
else:
lc1=linecontour[:inds[0]]
lc2= linecontour[inds[-1]+1:]
else:
lc1=linecontour[:ind]
lc2 = linecontour[ind+1:]
if rot <0:
new_x1, new_y1 = x-xlabel, y+ylabel
new_x2, new_y2 = x+xlabel, y-ylabel
else:
new_x1, new_y1 = x-xlabel, y-ylabel
new_x2, new_y2 = x+xlabel, y+ylabel
new_x1d, new_y1d = trans.inverse_xy_tup((new_x1, new_y1))
new_x2d, new_y2d = trans.inverse_xy_tup((new_x2, new_y2))
if rot > 0:
if len(lc1) > 0 and (lc1[-1][0] <= new_x1d) and (lc1[-1][1] <= new_y1d):
lc1.append((new_x1d, new_y1d))
if len(lc2) > 0 and (lc2[0][0] >= new_x2d) and (lc2[0][1] >= new_y2d):
lc2.insert(0, (new_x2d, new_y2d))
else:
if len(lc1) > 0 and ((lc1[-1][0] <= new_x1d) and (lc1[-1][1] >= new_y1d)):
lc1.append((new_x1d, new_y1d))
if len(lc2) > 0 and ((lc2[0][0] >= new_x2d) and (lc2[0][1] <= new_y2d)):
lc2.insert(0, (new_x2d, new_y2d))
return [lc1,lc2]
def locate_label(self, linecontour, labelwidth):
"""find a good place to plot a label (relatively flat
part of the contour) and the angle of rotation for the
text object
"""
nsize= len(linecontour)
if labelwidth > 1:
xsize = int(ceil(nsize/labelwidth))
else:
xsize = 1
if xsize == 1:
ysize = nsize
else:
ysize = labelwidth
XX = resize(array(linecontour)[:,0],(xsize, ysize))
YY = resize(array(linecontour)[:,1],(xsize,ysize))
yfirst = YY[:,0]
ylast = YY[:,-1]
xfirst = XX[:,0]
xlast = XX[:,-1]
s = ( (reshape(yfirst, (xsize,1))-YY) *
(reshape(xlast,(xsize,1)) - reshape(xfirst,(xsize,1)))
- (reshape(xfirst,(xsize,1))-XX)
* (reshape(ylast,(xsize,1)) - reshape(yfirst,(xsize,1))) )
L=sqrt((xlast-xfirst)**2+(ylast-yfirst)**2)
dist = add.reduce(([(abs(s)[i]/L[i]) for i in range(xsize)]),-1)
x,y,ind = self.get_label_coords(dist, XX, YY, ysize, labelwidth)
angle = arctan2(ylast - yfirst, xlast - xfirst)
rotation = angle[ind]*180/pi
if rotation > 90:
rotation = rotation -180
if rotation < -90:
rotation = 180 + rotation
dind = list(linecontour).index((x,y))
return x,y, rotation, dind
def labels(self, inline):
levels = self.label_levels
fslist = self.fslist
trans = self.ax.transData
colors = self.label_mappable.to_rgba(self.label_cvalues)
fmt = self.fmt
for icon, lev, color, cvalue, fsize in zip(self.label_indices,
self.label_levels,
colors,
self.label_cvalues, fslist):
con = self.collections[icon]
toremove = []
toadd = []
lw = self.get_label_width(lev, fmt, fsize)
for segNum, linecontour in enumerate(con._segments):
# for closed contours add one more point to
# avoid division by zero
if linecontour[0] == linecontour[-1]:
linecontour.append(linecontour[1])
# transfer all data points to screen coordinates
slc = trans.seq_xy_tups(linecontour)
if self.print_label(slc,lw):
x,y, rotation, ind = self.locate_label(slc, lw)
# transfer the location of the label back to
# data coordinates
dx,dy = trans.inverse_xy_tup((x,y))
t = Text(dx, dy, rotation = rotation,
horizontalalignment='center',
verticalalignment='center')
text = self.get_text(lev,fmt)
self.set_label_props(t, text, color)
self.cl.append(t)
self.cl_cvalues.append(cvalue)
if inline:
new = self.break_linecontour(linecontour, rotation,
lw, ind)
toadd.extend(new)
#for c in new: toadd.append(c)
toremove.append(linecontour)
for c in toremove:
con._segments.remove(c)
for c in toadd:
con._segments.append(c)
class ContourLabeler:
def __init__(self, ax):
self.ax = ax
def clabel(self, *args, **kwargs):
"""
CLABEL(*args, **kwargs)
Function signatures
CLABEL(C) - plots contour labels,
C is the output of contour or a list of contours
CLABEL(C,V) - creates labels only for those contours, given in
a list V
CLABEL(C, **kwargs) - keyword args are explained below:
* fontsize = None: as described in http://matplotlib.sf.net/fonts.html
* colors = None:
- a tuple of matplotlib color args (string, float, rgb, etc),
different labels will be plotted in different colors in the order
specified
- one string color, e.g. colors = 'r' or colors = 'red', all labels
will be plotted in this color
- if colors == None, the color of each label matches the color
of the corresponding contour
* inline = 0: controls whether the underlying contour is removed
(inline = 1) or not
* fmt = '%1.3f': a format string for the label
"""
# todo, factor this out to a separate class and don't use hidden coll attrs
if not self.ax.ishold(): self.ax.cla()
fontsize = kwargs.get('fontsize', None)
inline = kwargs.get('inline', 0)
fmt = kwargs.get('fmt', '%1.3f')
colors = kwargs.get('colors', None)
if len(args) == 1:
contours = args[0]
levels = [con._label for con in contours]
elif len(args) == 2:
contours = args[0]
levels = args[1]
else:
raise TypeError("Illegal arguments to clabel, see help(clabel)")
self.fp = FontProperties()
if fontsize == None:
font_size = int(self.fp.get_size_in_points())
else:
if type(fontsize) not in [int, float, str]:
raise TypeError("Font size must be an integer number.")
else:
if type(fontsize) == str:
font_size = int(self.fp.get_size_in_points())
else:
self.fp.set_size(fontsize)
font_size = fontsize
fslist = [font_size] * len(levels)
if colors == None:
colors = [c._colors[0] for c in contours]
else:
colors = colors * len(contours)
if inline not in [0,1]:
raise TypeError("inline must be 0 or 1")
self.cl = []
self.cl_xy = []
# we have a list of contours and each contour has a list of
# segments. We want changes in the contour color to be
# reflected in changes in the label color. This is a good use
# for traits observers, but in the interim, until traits are
# utilized, we'll create a dict mapping i,j to text instances.
# i is the contour level index, j is the sement index
self.labeld = {}
if inline == 1:
self.inline_labels(levels, contours, colors, fslist, fmt)
else:
self.labels(levels, contours, colors, fslist, fmt)
for label in self.cl:
self.ax.add_artist(label)
ret = silent_list('Text', self.cl)
ret.mappable = getattr(contours, 'mappable', None)
# support colormapping for label
if ret.mappable is not None:
ret.mappable.labeld = self.labeld
return ret
def print_label(self, linecontour,labelwidth):
"if contours are too short, don't plot a label"
lcsize = len(linecontour)
if lcsize > 10 * labelwidth:
return 1
xmax = amax(array(linecontour)[:,0])
xmin = amin(array(linecontour)[:,0])
ymax = amax(array(linecontour)[:,1])
ymin = amin(array(linecontour)[:,1])
lw = labelwidth
if (xmax - xmin) > 1.2* lw or (ymax - ymin) > 1.2 * lw:
return 1
else:
return 0
def too_close(self, x,y, lw):
"if there's a label already nearby, find a better place"
if self.cl_xy != []:
dist = [sqrt((x-loc[0]) ** 2 + (y-loc[1]) ** 2) for loc in self.cl_xy]
for d in dist:
if d < 1.2*lw:
return 1
else: return 0
else: return 0
def get_label_coords(self, distances, XX, YY, ysize, lw):
""" labels are ploted at a location with the smallest
dispersion of the contour from a straight line
unless there's another label nearby, in which case
the second best place on the contour is picked up
if there's no good place a label isplotted at the
beginning of the contour
"""
hysize = int(ysize/2)
adist = argsort(distances)
for ind in adist:
x, y = XX[ind][hysize], YY[ind][hysize]
if self.too_close(x,y, lw):
continue
else:
self.cl_xy.append((x,y))
return x,y, ind
ind = adist[0]
x, y = XX[ind][hysize], YY[ind][hysize]
self.cl_xy.append((x,y))
return x,y, ind
def get_label_width(self, lev, fmt, fsize):
"get the width of the label in points"
if is_string_like(lev):
lw = (len(lev)) * fsize
else:
lw = (len(fmt%lev)) * fsize
return lw
def set_label_props(self, label,text, color):
"set the label properties - color, fontsize, text"
label.set_text(text)
label.set_color(color)
label.set_fontproperties(self.fp)
label.set_clip_box(self.ax.bbox)
def get_text(self, lev, fmt):
"get the text of the label"
if is_string_like(lev):
return lev
else:
return fmt%lev
def break_linecontour(self, linecontour, rot, labelwidth, ind):
"break a contour in two contours at the location of the label"
lcsize = len(linecontour)
hlw = int(labelwidth/2)
#length of label in screen coords
ylabel = abs(hlw * sin(rot*pi/180))
xlabel = abs(hlw * cos(rot*pi/180))
trans = self.ax.transData
slc = trans.seq_xy_tups(linecontour)
x,y = slc[ind]
xx= array(slc)[:,0].copy()
yy=array(slc)[:,1].copy()
#indices which are under the label
inds=nonzero(((xx < x+xlabel) & (xx > x-xlabel)) & ((yy < y+ylabel) & (yy > y-ylabel)))
if len(inds) >0:
#if the label happens to be over the beginning of the
#contour, the entire contour is removed, i.e.
#indices to be removed are
#inds= [0,1,2,3,305,306,307]
#should rewrite this in a better way
linds = nonzero(inds[1:]- inds[:-1] != 1)
if inds[0] == 0 and len(linds) != 0:
ii = inds[linds[0]]
lc1 =linecontour[ii+1:inds[ii+1]]
lc2 = []
else:
lc1=linecontour[:inds[0]]
lc2= linecontour[inds[-1]+1:]
else:
lc1=linecontour[:ind]
lc2 = linecontour[ind+1:]
if rot <0:
new_x1, new_y1 = x-xlabel, y+ylabel
new_x2, new_y2 = x+xlabel, y-ylabel
else:
new_x1, new_y1 = x-xlabel, y-ylabel
new_x2, new_y2 = x+xlabel, y+ylabel
new_x1d, new_y1d = trans.inverse_xy_tup((new_x1, new_y1))
new_x2d, new_y2d = trans.inverse_xy_tup((new_x2, new_y2))
if rot > 0:
if len(lc1) > 0 and (lc1[-1][0] <= new_x1d) and (lc1[-1][1] <= new_y1d):
lc1.append((new_x1d, new_y1d))
if len(lc2) > 0 and (lc2[0][0] >= new_x2d) and (lc2[0][1] >= new_y2d):
lc2.insert(0, (new_x2d, new_y2d))
else:
if len(lc1) > 0 and ((lc1[-1][0] <= new_x1d) and (lc1[-1][1] >= new_y1d)):
lc1.append((new_x1d, new_y1d))
if len(lc2) > 0 and ((lc2[0][0] >= new_x2d) and (lc2[0][1] <= new_y2d)):
lc2.insert(0, (new_x2d, new_y2d))
return [lc1,lc2]
def locate_label(self, linecontour, labelwidth):
"""find a good place to plot a label (relatively flat
part of the contour) and the angle of rotation for the
text object
"""
nsize= len(linecontour)
if labelwidth > 1:
xsize = int(ceil(nsize/labelwidth))
else:
xsize = 1
if xsize == 1:
ysize = nsize
else:
ysize = labelwidth
XX = resize(array(linecontour)[:,0],(xsize, ysize))
YY = resize(array(linecontour)[:,1],(xsize,ysize))
yfirst = YY[:,0]
ylast = YY[:,-1]
xfirst = XX[:,0]
xlast = XX[:,-1]
s = (reshape(yfirst, (xsize,1))-YY)*(reshape(xlast,(xsize,1))-reshape(xfirst,(xsize,1)))-(reshape(xfirst,(xsize,1))-XX)*(reshape(ylast,(xsize,1))-reshape(yfirst,(xsize,1)))
L=sqrt((xlast-xfirst)**2+(ylast-yfirst)**2)
dist = add.reduce(([(abs(s)[i]/L[i]) for i in range(xsize)]),-1)
x,y,ind = self.get_label_coords(dist, XX, YY, ysize, labelwidth)
angle = arctan2(ylast - yfirst, xlast - xfirst)
rotation = angle[ind]*180/pi
if rotation > 90:
rotation = rotation -180
if rotation < -90:
rotation = 180 + rotation
dind = list(linecontour).index((x,y))
return x,y, rotation, dind
def inline_labels(self, levels, contours, colors, fslist, fmt):
trans = self.ax.transData
contourNum = 0
for lev, con, color, fsize in zip(levels, contours, colors, fslist):
toremove = []
toadd = []
lw = self.get_label_width(lev, fmt, fsize)
for segNum, linecontour in enumerate(con._segments):
key = contourNum, segNum
# for closed contours add one more point to
# avoid division by zero
if linecontour[0] == linecontour[-1]:
linecontour.append(linecontour[1])
# transfer all data points to screen coordinates
slc = trans.seq_xy_tups(linecontour)
if self.print_label(slc,lw):
x,y, rotation, ind = self.locate_label(slc, lw)
# transfer the location of the label back to
# data coordinates
dx,dy = trans.inverse_xy_tup((x,y))
t = Text(dx, dy, rotation = rotation, horizontalalignment='center', verticalalignment='center')
self.labeld[key] = t
text = self.get_text(lev,fmt)
self.set_label_props(t, text, color)
self.cl.append(t)
new = self.break_linecontour(linecontour, rotation, lw, ind)
for c in new: toadd.append(c)
toremove.append(linecontour)
for c in toremove:
con._segments.remove(c)
for c in toadd: con._segments.append(c)
contourNum += 1
def labels(self, levels, contours, colors, fslist, fmt):
trans = self.ax.transData
for lev, con, color, fsize in zip(levels, contours, colors, fslist):
lw = self.get_label_width(lev, fmt, fsize)
for linecontour in con._segments:
# for closed contours add one more point
if linecontour[0] == linecontour[-1]:
linecontour.append(linecontour[1])
# transfer all data points to screen coordinates
slc = trans.seq_xy_tups(linecontour)
if self.print_label(slc,lw):
x,y, rotation, ind = self.locate_label(slc, lw)
# transfer the location of the label back into
# data coordinates
dx,dy = trans.inverse_xy_tup((x,y))
t = Text(dx, dy, rotation = rotation, horizontalalignment='center', verticalalignment='center')
text = self.get_text(lev, fmt)
self.set_label_props(t, text, color)
self.cl.append(t)
else:
pass