def topoplot(values=None, axes=None, center=(0,0), nose_dir=0., radius=0.5,
sensors=None, colors=('black','black','black'),
linewidths=(3,2,2,0.5), contours_ls='-', contours=15, resolution=400,
cmap=None, axis_props='off', plot_mask='circular'):
"""
Plot a topographic map of the scalp in a 2-D circular view
(looking down at the top of the head).
Parameters
----------
values : {None, array-like}, optional
Values to plot. There must be one value for each electrode.
axes : {matplotlib.axes}, optional
Axes to which the topoplot should be added.
center : {tuple of floats}, optional
x and y coordinates of the center of the head.
nose_dir : {float}, optional
Angle (in degrees) where the nose is pointing. 0 is
up, 90 is left, 180 is down, 270 is right, etc.
radius : {float}, optional
Radius of the head.
sensors : {None, tuple of floats}, optional
Polar coordinates of the sensor locations. If not None,
sensors[0] specifies the angle (in degrees) and sensors[1]
specifies the radius.
colors : {tuple of str or None}, optional
Colors for the outline of the head, sensor markers, and contours
respectively. If any is None, the corresponding feature is
not plotted. For contours either a single color or
multiple colors can be specified.
linewidths : {tuple of floats}, optional
Line widths for the head, nose, ears, and contours
respectively. For contours either a single linewith or
multiple linewidths can be specified.
contours_ls : {str}, optional
Line style of the contours.
contours : {int}, optional
Number of countours.
resolution : {int}, optional
Resolution of the interpolated grid. Higher numbers give
smoother edges of the plot, but increase memory and
computational demands.
cmap : {None,matplotlib.colors.LinearSegmentedColormap}, optional
Color map for the contour plot. If colMap==None, the default
color map is used.
axis_props : {str}, optional
Axis properties.
plot_mask : {str}, optional
The mask around the plotted values. 'linear' conects the outer
electrodes with straight lines, 'circular' draws a circle
around the outer electrodes, and 'square' (or any other value)
draws a square around the electrodes.
"""
# If no colormap is specified, use default colormap:
if cmap is None:
cmap = plt.get_cmap()
if axes is not None: # axes are given
a=axes
else: # a new subplot is created
a=plt.subplot(1,1,1, aspect='equal')
plt.axis(axis_props)
if colors[0]: # head should be plotted
# Set up head
head = plt.Circle(center, radius,fill=False, linewidth=linewidths[0],
edgecolor=colors[0])
# Nose:
nose_width = 0.18*radius
# Distance from the center of the head to the point where the
# nose touches the outline of the head:
nose_dist = np.cos(np.arcsin((nose_width/2.)/radius))*radius
# Distance from the center of the head to the tip of the nose:
nose_tip_dist = 1.15*radius
# Convert to polar coordinates for rotating:
nose_polar_angle,nose_polar_radius = cart2pol(
np.array([-nose_width/2,0,nose_width/2]),
np.array([nose_dist,nose_tip_dist,nose_dist]))
nose_polar_angle = nose_polar_angle+deg2rad(nose_dir)
# And back to cartesian coordinates for plotting:
nose_x,nose_y = pol2cart(nose_polar_angle,nose_polar_radius)
# Move nose with head:
nose_x = nose_x + center[0]
nose_y = nose_y + center[1]
nose = plt.Line2D(nose_x,nose_y,color=colors[0],linewidth=linewidths[1],
solid_joinstyle='round',solid_capstyle='round')
# Ears:
q = .04 # ear lengthening
ear_x = np.array([.497-.005,.510,.518,.5299,
.5419,.54,.547,.532,.510,.489-.005])*(radius/0.5)
ear_y = np.array([q+.0555,q+.0775,q+.0783,q+.0746,q+.0555,
-.0055,-.0932,-.1313,-.1384,-.1199])*(radius/0.5)
# Convert to polar coordinates for rotating:
rightear_polar_angle,rightear_polar_radius = cart2pol(ear_x,ear_y)
leftear_polar_angle,leftear_polar_radius = cart2pol(-ear_x,ear_y)
rightear_polar_angle=rightear_polar_angle+deg2rad(nose_dir)
leftear_polar_angle=leftear_polar_angle+deg2rad(nose_dir)
# And back to cartesian coordinates for plotting:
rightear_x,rightear_y=pol2cart(rightear_polar_angle,
rightear_polar_radius)
leftear_x,leftear_y=pol2cart(leftear_polar_angle,leftear_polar_radius)
# Move ears with head:
rightear_x = rightear_x + center[0]
rightear_y = rightear_y + center[1]
leftear_x = leftear_x + center[0]
leftear_y = leftear_y + center[1]
ear_right = plt.Line2D(rightear_x,rightear_y,color=colors[0],
linewidth=linewidths[3],solid_joinstyle='round',
solid_capstyle='round')
ear_left = plt.Line2D(leftear_x,leftear_y,color=colors[0],
linewidth=linewidths[3],solid_joinstyle='round',
solid_capstyle='round')
a.add_artist(head)
a.add_artist(nose)
a.add_artist(ear_right)
a.add_artist(ear_left)
if sensors is None:
if axes is None:
plt.xlim(-radius*1.2+center[0],radius*1.2+center[0])
plt.ylim(-radius*1.2+center[1],radius*1.2+center[1])
return("No sensor locations specified!")
# Convert & rotate sensor locations:
angles=sensors[0]
angles=angles+nose_dir
angles = deg2rad(angles)
radii=sensors[1]
# expand or shrink electrode locations with radius of head:
radii = radii*(radius/0.5)
# plotting radius is determined by largest sensor radius:
plot_radius = max(radii)
# convert electrode locations to cartesian coordinates for plotting:
x,y = pol2cart(angles,radii)
x = x + center[0]
y = y + center[1]
if colors[1]: # plot electrodes
plt.plot(x,y,markerfacecolor=colors[1],marker='o',linestyle='')
if values is None:
return('No values to plot specified!')
if np.size(values) != np.size(sensors,1):
return('Numer of values to plot is different from number of sensors!'+
'\nNo values have been plotted!')
z = values
# resolution determines the number of interpolated points per unit
nx = round(resolution*plot_radius)
ny = round(resolution*plot_radius)
# now set up the grid:
xi, yi = np.meshgrid(np.linspace(-plot_radius,plot_radius,nx),
np.linspace(-plot_radius,plot_radius,ny))
# and move the center to coincide with the center of the head:
xi = xi + center[0]
yi = yi + center[1]
# interploate points:
if plot_mask=='linear':
# masked = True means that no extrapolation outside the
# electrode boundaries is made this effectively creates a mask
# with a linear boundary (connecting the outer electrode
# locations)
#zi = griddata(x,y,z,xi,yi,masked=True)
zi = griddata(x,y,z,xi,yi)
else:
# we need a custom mask:
#zi = griddata(x,y,z,xi,yi,ext=1,masked=False)
zi = griddata(x,y,z,xi,yi)
if plot_mask=='circular':
# the interpolated array doesn't know about its position
# in space and hence we need to subtract head center from
# xi & xi to calculate the mask
mask = (np.sqrt(np.power(xi-center[0],2) +
np.power(yi-center[1],2)) > plot_radius)
zi[mask] = 0
# other masks may be added here and can be defined as shown
# for the circular mask. All other plot_mask values result in
# no mask which results in showing interpolated values for the
# square surrounding the head.
# make contour lines:
if linewidths[3] > 0:
plt.contour(xi,yi,zi,contours,linewidths=linewidths[3],
linestyle=contours_ls,colors=colors[2])
# make countour color patches:
plt.contourf(xi,yi,zi,contours,cmap=cmap)
def topoplot(values=None, labels=None, sensors=None, axes=None,
center=(0,0), nose_dir=0., radius=0.5,
head_props=None, sensor_props=None,
label_props=None,
contours=15, contour_props=None,
resolution=400, cmap=None, axis_props='off',
plot_mask='circular', plot_radius_buffer=.2):
"""
Plot a topographic map of the scalp in a 2-D circular view
(looking down at the top of the head).
Parameters
----------
values : {None, array-like}, optional
Values to plot. There must be one value for each electrode.
labels : {None, array-like}, optional
Electrode labels/names to plot. There must be one for each electrode.
sensors : {None, tuple of floats}, optional
Polar coordinates of the sensor locations. If not None,
sensors[0] specifies the angle (in degrees) and sensors[1]
specifies the radius.
axes : {matplotlib.axes}, optional
Axes to which the topoplot should be added.
center : {tuple of floats}, optional
x and y coordinates of the center of the head.
nose_dir : {float}, optional
Angle (in degrees) where the nose is pointing. 0 is
up, 90 is left, 180 is down, 270 is right, etc.
radius : {float}, optional
Radius of the head.
head_props : dict
Dictionary of head properties. See default_head_props for choices.
sensor_props : dict
Dictionary of sensor properties. See options for scatter in mpl and
default_sensor_props.
label_props : dict
Dictionary of sensor label properties. See options for text in mpl
and default_label_props.
contours : {int}, optional
Number of contours.
contour_props : dict
Dictionary of contour properties. See options for contour in mpl and
default_contour_props.
resolution : {int}, optional
Resolution of the interpolated grid. Higher numbers give
smoother edges of the plot, but increase memory and
computational demands.
cmap : {None,matplotlib.colors.LinearSegmentedColormap}, optional
Color map for the contour plot. If colMap==None, the default
color map is used.
axis_props : {str}, optional
Axis properties.
plot_mask : {str}, optional
The mask around the plotted values. 'linear' conects the outer
electrodes with straight lines, 'circular' draws a circle
around the outer electrodes (see plot_radius_buffer).
plot_radius_buffer : float, optional
Buffer outside the electrode circumference for generating
interpolated values with a circular mask.
This should be greater than zero to aviod interpolation errors.
"""
if axes is not None: # axes are given
a=axes
else: # a new subplot is created
a=plt.subplot(1,1,1, aspect='equal')
plt.axis(axis_props)
if True: # head should be plotted
# deal with the head props
hprops = default_head_props.copy()
if not head_props is None:
hprops.update(head_props)
# Set up head
head = plt.Circle(center, radius, fill=False,
linewidth=hprops['head_linewidth'],
edgecolor=hprops['head_linecolor'])
# Nose:
nose_width = 0.18*radius
# Distance from the center of the head to the point where the
# nose touches the outline of the head:
nose_dist = np.cos(np.arcsin((nose_width/2.)/radius))*radius
# Distance from the center of the head to the tip of the nose:
nose_tip_dist = 1.15*radius
# Convert to polar coordinates for rotating:
nose_polar_angle,nose_polar_radius = cart2pol(
np.array([-nose_width/2,0,nose_width/2]),
np.array([nose_dist,nose_tip_dist,nose_dist]))
nose_polar_angle = nose_polar_angle+deg2rad(nose_dir)
# And back to cartesian coordinates for plotting:
nose_x,nose_y = pol2cart(nose_polar_angle,nose_polar_radius)
# Move nose with head:
nose_x = nose_x + center[0]
nose_y = nose_y + center[1]
nose = plt.Line2D(nose_x,nose_y,
solid_joinstyle='round',solid_capstyle='round',
color=hprops['head_linecolor'],
linewidth=hprops['nose_linewidth'])
# Ears:
q = .04 # ear lengthening
ear_x = np.array([.497-.005,.510,.518,.5299,
.5419,.54,.547,.532,.510,.489-.005])*(radius/0.5)
ear_y = np.array([q+.0555,q+.0775,q+.0783,q+.0746,q+.0555,
-.0055,-.0932,-.1313,-.1384,-.1199])*(radius/0.5)
# Convert to polar coordinates for rotating:
rightear_polar_angle,rightear_polar_radius = cart2pol(ear_x,ear_y)
leftear_polar_angle,leftear_polar_radius = cart2pol(-ear_x,ear_y)
rightear_polar_angle=rightear_polar_angle+deg2rad(nose_dir)
leftear_polar_angle=leftear_polar_angle+deg2rad(nose_dir)
# And back to cartesian coordinates for plotting:
rightear_x,rightear_y=pol2cart(rightear_polar_angle,
rightear_polar_radius)
leftear_x,leftear_y=pol2cart(leftear_polar_angle,leftear_polar_radius)
# Move ears with head:
rightear_x = rightear_x + center[0]
rightear_y = rightear_y + center[1]
leftear_x = leftear_x + center[0]
leftear_y = leftear_y + center[1]
ear_right = plt.Line2D(rightear_x,rightear_y,color=hprops['head_linecolor'],
linewidth=hprops['ear_linewidth'],
solid_joinstyle='round',
solid_capstyle='round')
ear_left = plt.Line2D(leftear_x,leftear_y,color=hprops['head_linecolor'],
linewidth=hprops['ear_linewidth'],
solid_joinstyle='round',
solid_capstyle='round')
a.add_artist(head)
a.add_artist(nose)
a.add_artist(ear_right)
a.add_artist(ear_left)
if sensors is None:
if axes is None:
plt.xlim(-radius*1.2+center[0],radius*1.2+center[0])
plt.ylim(-radius*1.2+center[1],radius*1.2+center[1])
return("No sensor locations specified!")
# Convert & rotate sensor locations:
angles=sensors[0]
angles=angles+nose_dir
angles = deg2rad(angles)
radii=sensors[1]
# expand or shrink electrode locations with radius of head:
radii = radii*(radius/0.5)
# plotting radius is determined by largest sensor radius:
plot_radius = max(radii)*(1.0+plot_radius_buffer)
# convert electrode locations to cartesian coordinates for plotting:
x,y = pol2cart(angles,radii)
x = x + center[0]
y = y + center[1]
if True: # plot electrodes
sprops = default_sensor_props.copy()
if not sensor_props is None:
sprops.update(sensor_props)
#a.plot(x,y,markerfacecolor=colors[1],marker='o',linestyle='')
a.scatter(x, y, zorder=10, **sprops)
if not labels is None:
lprops = default_label_props.copy()
if not label_props is None:
lprops.update(label_props)
for i in range(len(labels)):
a.text(x[i],y[i],labels[i],**lprops)
if values is None:
return #('No values to plot specified!')
if np.size(values) != np.size(sensors,1):
return('Numer of values to plot is different from number of sensors!'+
'\nNo values have been plotted!')
# set the values
z = values
# resolution determines the number of interpolated points per unit
nx = round(resolution*plot_radius)
ny = round(resolution*plot_radius)
# now set up the grid:
xi, yi = np.meshgrid(np.linspace(-plot_radius,plot_radius,nx),
np.linspace(-plot_radius,plot_radius,ny))
# and move the center to coincide with the center of the head:
xi = xi + center[0]
yi = yi + center[1]
# interploate points:
if plot_mask=='linear':
# masked = True means that no extrapolation outside the
# electrode boundaries is made this effectively creates a mask
# with a linear boundary (connecting the outer electrode
# locations)
#zi = griddata(x,y,z,xi,yi,masked=True)
#zi = griddata(x,y,z,xi,yi)
pass
elif plot_mask=='circular':
npts = np.mean((nx,ny))*2
t = np.linspace(0,2*np.pi,npts)[:-1]
x = np.r_[x,np.cos(t)*plot_radius]
y = np.r_[y,np.sin(t)*plot_radius]
z = np.r_[z,np.zeros(len(t))]
else:
# we need a custom mask:
#zi = griddata(x,y,z,xi,yi,ext=1,masked=False)
#zi = griddata(x,y,z,xi,yi)
# zi = griddata((x,y),z,(xi,yi),method='cubic')
# if plot_mask=='circular':
# # the interpolated array doesn't know about its position
# # in space and hence we need to subtract head center from
# # xi & xi to calculate the mask
# mask = (np.sqrt(np.power(xi-center[0],2) +
# np.power(yi-center[1],2)) > plot_radius)
# zi[mask] = 0
# zi[np.isnan(zi)] = 0.0
# zi[mask] = np.nan
# other masks may be added here and can be defined as shown
# for the circular mask. All other plot_mask values result in
# no mask which results in showing interpolated values for the
# square surrounding the head.
pass
# calc the grid
zi = griddata((x,y),z,(xi,yi),method='cubic')
# If no colormap is specified, use default colormap:
if cmap is None:
cmap = plt.get_cmap()
# make contours
cprops = default_contour_props.copy()
if not contour_props is None:
cprops.update(contour_props)
if np.any(cprops['linewidths'] > 0):
plt.contour(xi,yi,zi,contours,**cprops)
# make countour color patches:
plt.contourf(xi,yi,zi,contours,cmap=cmap,extend='both')
def topoplot(values=None,
labels=None,
sensors=None,
axes=None,
center=(0, 0),
nose_dir=0.,
radius=0.5,
head_props=None,
sensor_props=None,
label_props=None,
contours=15,
contour_props=None,
resolution=400,
cmap=None,
axis_props='off',
plot_mask='circular',
plot_radius_buffer=.2):
"""
Plot a topographic map of the scalp in a 2-D circular view
(looking down at the top of the head).
Parameters
----------
values : {None, array-like}, optional
Values to plot. There must be one value for each electrode.
labels : {None, array-like}, optional
Electrode labels/names to plot. There must be one for each electrode.
sensors : {None, tuple of floats}, optional
Polar coordinates of the sensor locations. If not None,
sensors[0] specifies the angle (in degrees) and sensors[1]
specifies the radius.
axes : {matplotlib.axes}, optional
Axes to which the topoplot should be added.
center : {tuple of floats}, optional
x and y coordinates of the center of the head.
nose_dir : {float}, optional
Angle (in degrees) where the nose is pointing. 0 is
up, 90 is left, 180 is down, 270 is right, etc.
radius : {float}, optional
Radius of the head.
head_props : dict
Dictionary of head properties. See default_head_props for choices.
sensor_props : dict
Dictionary of sensor properties. See options for scatter in mpl and
default_sensor_props.
label_props : dict
Dictionary of sensor label properties. See options for text in mpl
and default_label_props.
contours : {int}, optional
Number of contours.
contour_props : dict
Dictionary of contour properties. See options for contour in mpl and
default_contour_props.
resolution : {int}, optional
Resolution of the interpolated grid. Higher numbers give
smoother edges of the plot, but increase memory and
computational demands.
cmap : {None,matplotlib.colors.LinearSegmentedColormap}, optional
Color map for the contour plot. If colMap==None, the default
color map is used.
axis_props : {str}, optional
Axis properties.
plot_mask : {str}, optional
The mask around the plotted values. 'linear' conects the outer
electrodes with straight lines, 'circular' draws a circle
around the outer electrodes (see plot_radius_buffer).
plot_radius_buffer : float, optional
Buffer outside the electrode circumference for generating
interpolated values with a circular mask.
This should be greater than zero to aviod interpolation errors.
"""
if axes is not None: # axes are given
a = axes
else: # a new subplot is created
a = plt.subplot(1, 1, 1, aspect='equal')
plt.axis(axis_props)
if True: # head should be plotted
# deal with the head props
hprops = default_head_props.copy()
if not head_props is None:
hprops.update(head_props)
# Set up head
head = plt.Circle(center,
radius,
fill=False,
linewidth=hprops['head_linewidth'],
edgecolor=hprops['head_linecolor'])
# Nose:
nose_width = 0.18 * radius
# Distance from the center of the head to the point where the
# nose touches the outline of the head:
nose_dist = np.cos(np.arcsin((nose_width / 2.) / radius)) * radius
# Distance from the center of the head to the tip of the nose:
nose_tip_dist = 1.15 * radius
# Convert to polar coordinates for rotating:
nose_polar_angle, nose_polar_radius = cart2pol(
np.array([-nose_width / 2, 0, nose_width / 2]),
np.array([nose_dist, nose_tip_dist, nose_dist]))
nose_polar_angle = nose_polar_angle + deg2rad(nose_dir)
# And back to cartesian coordinates for plotting:
nose_x, nose_y = pol2cart(nose_polar_angle, nose_polar_radius)
# Move nose with head:
nose_x = nose_x + center[0]
nose_y = nose_y + center[1]
nose = plt.Line2D(nose_x,
nose_y,
solid_joinstyle='round',
solid_capstyle='round',
color=hprops['head_linecolor'],
linewidth=hprops['nose_linewidth'])
# Ears:
q = .04 # ear lengthening
ear_x = np.array([
.497 - .005, .510, .518, .5299, .5419, .54, .547, .532, .510,
.489 - .005
]) * (radius / 0.5)
ear_y = np.array([
q + .0555, q + .0775, q + .0783, q + .0746, q + .0555, -.0055,
-.0932, -.1313, -.1384, -.1199
]) * (radius / 0.5)
# Convert to polar coordinates for rotating:
rightear_polar_angle, rightear_polar_radius = cart2pol(ear_x, ear_y)
leftear_polar_angle, leftear_polar_radius = cart2pol(-ear_x, ear_y)
rightear_polar_angle = rightear_polar_angle + deg2rad(nose_dir)
leftear_polar_angle = leftear_polar_angle + deg2rad(nose_dir)
# And back to cartesian coordinates for plotting:
rightear_x, rightear_y = pol2cart(rightear_polar_angle,
rightear_polar_radius)
leftear_x, leftear_y = pol2cart(leftear_polar_angle,
leftear_polar_radius)
# Move ears with head:
rightear_x = rightear_x + center[0]
rightear_y = rightear_y + center[1]
leftear_x = leftear_x + center[0]
leftear_y = leftear_y + center[1]
ear_right = plt.Line2D(rightear_x,
rightear_y,
color=hprops['head_linecolor'],
linewidth=hprops['ear_linewidth'],
solid_joinstyle='round',
solid_capstyle='round')
ear_left = plt.Line2D(leftear_x,
leftear_y,
color=hprops['head_linecolor'],
linewidth=hprops['ear_linewidth'],
solid_joinstyle='round',
solid_capstyle='round')
a.add_artist(head)
a.add_artist(nose)
a.add_artist(ear_right)
a.add_artist(ear_left)
if sensors is None:
if axes is None:
plt.xlim(-radius * 1.2 + center[0], radius * 1.2 + center[0])
plt.ylim(-radius * 1.2 + center[1], radius * 1.2 + center[1])
return ("No sensor locations specified!")
# Convert & rotate sensor locations:
angles = sensors[0]
angles = angles + nose_dir
angles = deg2rad(angles)
radii = sensors[1]
# expand or shrink electrode locations with radius of head:
radii = radii * (radius / 0.5)
# plotting radius is determined by largest sensor radius:
plot_radius = max(radii) * (1.0 + plot_radius_buffer)
# convert electrode locations to cartesian coordinates for plotting:
x, y = pol2cart(angles, radii)
x = x + center[0]
y = y + center[1]
if True: # plot electrodes
sprops = default_sensor_props.copy()
if not sensor_props is None:
sprops.update(sensor_props)
#a.plot(x,y,markerfacecolor=colors[1],marker='o',linestyle='')
a.scatter(x, y, zorder=10, **sprops)
if not labels is None:
lprops = default_label_props.copy()
if not label_props is None:
lprops.update(label_props)
for i in range(len(labels)):
a.text(x[i], y[i], labels[i], **lprops)
if values is None:
return #('No values to plot specified!')
if np.size(values) != np.size(sensors, 1):
return (
'Numer of values to plot is different from number of sensors!' +
'\nNo values have been plotted!')
# set the values
z = values
# resolution determines the number of interpolated points per unit
nx = round(resolution * plot_radius)
ny = round(resolution * plot_radius)
# now set up the grid:
xi, yi = np.meshgrid(np.linspace(-plot_radius, plot_radius, nx),
np.linspace(-plot_radius, plot_radius, ny))
# and move the center to coincide with the center of the head:
xi = xi + center[0]
yi = yi + center[1]
# interploate points:
if plot_mask == 'linear':
# masked = True means that no extrapolation outside the
# electrode boundaries is made this effectively creates a mask
# with a linear boundary (connecting the outer electrode
# locations)
#zi = griddata(x,y,z,xi,yi,masked=True)
#zi = griddata(x,y,z,xi,yi)
pass
elif plot_mask == 'circular':
npts = np.mean((nx, ny)) * 2
t = np.linspace(0, 2 * np.pi, npts)[:-1]
x = np.r_[x, np.cos(t) * plot_radius]
y = np.r_[y, np.sin(t) * plot_radius]
z = np.r_[z, np.zeros(len(t))]
else:
# we need a custom mask:
#zi = griddata(x,y,z,xi,yi,ext=1,masked=False)
#zi = griddata(x,y,z,xi,yi)
# zi = griddata((x,y),z,(xi,yi),method='cubic')
# if plot_mask=='circular':
# # the interpolated array doesn't know about its position
# # in space and hence we need to subtract head center from
# # xi & xi to calculate the mask
# mask = (np.sqrt(np.power(xi-center[0],2) +
# np.power(yi-center[1],2)) > plot_radius)
# zi[mask] = 0
# zi[np.isnan(zi)] = 0.0
# zi[mask] = np.nan
# other masks may be added here and can be defined as shown
# for the circular mask. All other plot_mask values result in
# no mask which results in showing interpolated values for the
# square surrounding the head.
pass
# calc the grid
zi = griddata((x, y), z, (xi, yi), method='cubic')
# If no colormap is specified, use default colormap:
if cmap is None:
cmap = plt.get_cmap()
# make contours
cprops = default_contour_props.copy()
if not contour_props is None:
cprops.update(contour_props)
if np.any(cprops['linewidths'] > 0):
plt.contour(xi, yi, zi, contours, **cprops)
# make countour color patches:
plt.contourf(xi, yi, zi, contours, cmap=cmap, extend='both')
def topoplot(values=None, axes=None, center=(0,0), nose_dir=0., radius=0.5,
sensors=None, colors=('black','black','black'),
linewidths=(3,2,2,0.5), contours_ls='-', contours=15, resolution=400,
cmap=None, axis_props='off', plot_mask='circular'):
"""
Plot a topographic map of the scalp in a 2-D circular view
(looking down at the top of the head).
Parameters
----------
values : {None, array-like}, optional
Values to plot. There must be one value for each electrode.
axes : {matplotlib.axes}, optional
Axes to which the topoplot should be added.
center : {tuple of floats}, optional
x and y coordinates of the center of the head.
nose_dir : {float}, optional
Angle (in degrees) where the nose is pointing. 0 is
up, 90 is left, 180 is down, 270 is right, etc.
radius : {float}, optional
Radius of the head.
sensors : {None, tuple of floats}, optional
Polar coordinates of the sensor locations. If not None,
sensors[0] specifies the angle (in degrees) and sensors[1]
specifies the radius.
colors : {tuple of str or None}, optional
Colors for the outline of the head, sensor markers, and contours
respectively. If any is None, the corresponding feature is
not plotted. For contours either a single color or
multiple colors can be specified.
linewidths : {tuple of floats}, optional
Line widths for the head, nose, ears, and contours
respectively. For contours either a single linewith or
multiple linewidths can be specified.
contours_ls : {str}, optional
Line style of the contours.
contours : {int}, optional
Number of countours.
resolution : {int}, optional
Resolution of the interpolated grid. Higher numbers give
smoother edges of the plot, but increase memory and
computational demands.
cmap : {None,matplotlib.colors.LinearSegmentedColormap}, optional
Color map for the contour plot. If colMap==None, the default
color map is used.
axis_props : {str}, optional
Axis properties.
plot_mask : {str}, optional
The mask around the plotted values. 'linear' conects the outer
electrodes with straight lines, 'circular' draws a circle
around the outer electrodes, and 'square' (or any other value)
draws a square around the electrodes.
"""
# If no colormap is specified, use default colormap:
if cmap is None:
cmap = plt.get_cmap()
if axes is not None: # axes are given
a=axes
else: # a new subplot is created
a=plt.subplot(1,1,1, aspect='equal')
plt.axis(axis_props)
if colors[0]: # head should be plotted
# Set up head
head = plt.Circle(center, radius,fill=False, linewidth=linewidths[0],
edgecolor=colors[0])
# Nose:
nose_width = 0.18*radius
# Distance from the center of the head to the point where the
# nose touches the outline of the head:
nose_dist = np.cos(np.arcsin((nose_width/2.)/radius))*radius
# Distance from the center of the head to the tip of the nose:
nose_tip_dist = 1.15*radius
# Convert to polar coordinates for rotating:
nose_polar_angle,nose_polar_radius = cart2pol(
np.array([-nose_width/2,0,nose_width/2]),
np.array([nose_dist,nose_tip_dist,nose_dist]))
nose_polar_angle = nose_polar_angle+deg2rad(nose_dir)
# And back to cartesian coordinates for plotting:
nose_x,nose_y = pol2cart(nose_polar_angle,nose_polar_radius)
# Move nose with head:
nose_x = nose_x + center[0]
nose_y = nose_y + center[1]
nose = plt.Line2D(nose_x,nose_y,color=colors[0],linewidth=linewidths[1],
solid_joinstyle='round',solid_capstyle='round')
# Ears:
q = .04 # ear lengthening
ear_x = np.array([.497-.005,.510,.518,.5299,
.5419,.54,.547,.532,.510,.489-.005])*(radius/0.5)
ear_y = np.array([q+.0555,q+.0775,q+.0783,q+.0746,q+.0555,
-.0055,-.0932,-.1313,-.1384,-.1199])*(radius/0.5)
# Convert to polar coordinates for rotating:
rightear_polar_angle,rightear_polar_radius = cart2pol(ear_x,ear_y)
leftear_polar_angle,leftear_polar_radius = cart2pol(-ear_x,ear_y)
rightear_polar_angle=rightear_polar_angle+deg2rad(nose_dir)
leftear_polar_angle=leftear_polar_angle+deg2rad(nose_dir)
# And back to cartesian coordinates for plotting:
rightear_x,rightear_y=pol2cart(rightear_polar_angle,
rightear_polar_radius)
leftear_x,leftear_y=pol2cart(leftear_polar_angle,leftear_polar_radius)
# Move ears with head:
rightear_x = rightear_x + center[0]
rightear_y = rightear_y + center[1]
leftear_x = leftear_x + center[0]
leftear_y = leftear_y + center[1]
ear_right = plt.Line2D(rightear_x,rightear_y,color=colors[0],
linewidth=linewidths[3],solid_joinstyle='round',
solid_capstyle='round')
ear_left = plt.Line2D(leftear_x,leftear_y,color=colors[0],
linewidth=linewidths[3],solid_joinstyle='round',
solid_capstyle='round')
a.add_artist(head)
a.add_artist(nose)
a.add_artist(ear_right)
a.add_artist(ear_left)
if sensors is None:
if axes is None:
plt.xlim(-radius*1.2+center[0],radius*1.2+center[0])
plt.ylim(-radius*1.2+center[1],radius*1.2+center[1])
return("No sensor locations specified!")
# Convert & rotate sensor locations:
angles=sensors[0]
angles=angles+nose_dir
angles = deg2rad(angles)
radii=sensors[1]
# expand or shrink electrode locations with radius of head:
radii = radii*(radius/0.5)
# plotting radius is determined by largest sensor radius:
plot_radius = max(radii)
# convert electrode locations to cartesian coordinates for plotting:
x,y = pol2cart(angles,radii)
x = x + center[0]
y = y + center[1]
if colors[1]: # plot electrodes
plt.plot(x,y,markerfacecolor=colors[1],marker='o',linestyle='')
if values is None:
return('No values to plot specified!')
if np.size(values) != np.size(sensors,1):
return('Numer of values to plot is different from number of sensors!'+
'\nNo values have been plotted!')
z = values
# resolution determines the number of interpolated points per unit
nx = round(resolution*plot_radius)
ny = round(resolution*plot_radius)
# now set up the grid:
xi, yi = np.meshgrid(np.linspace(-plot_radius,plot_radius,nx),
np.linspace(-plot_radius,plot_radius,ny))
# and move the center to coincide with the center of the head:
xi = xi + center[0]
yi = yi + center[1]
# interploate points:
if plot_mask=='linear':
# masked = True means that no extrapolation outside the
# electrode boundaries is made this effectively creates a mask
# with a linear boundary (connecting the outer electrode
# locations)
#zi = griddata(x,y,z,xi,yi,masked=True)
zi = griddata(x,y,z,xi,yi)
else:
# we need a custom mask:
#zi = griddata(x,y,z,xi,yi,ext=1,masked=False)
zi = griddata(x,y,z,xi,yi)
if plot_mask=='circular':
# the interpolated array doesn't know about its position
# in space and hence we need to subtract head center from
# xi & xi to calculate the mask
mask = (np.sqrt(np.power(xi-center[0],2) +
np.power(yi-center[1],2)) > plot_radius)
zi[mask] = 0
# other masks may be added here and can be defined as shown
# for the circular mask. All other plot_mask values result in
# no mask which results in showing interpolated values for the
# square surrounding the head.
# make contour lines:
plt.contour(xi,yi,zi,contours,linewidths=linewidths[3],
linestyle=contours_ls,colors=colors[2])
# make countour color patches:
plt.contourf(xi,yi,zi,contours,cmap=cmap)