# Source code for sfepy.postprocess.plot_dofs

```"""
Functions to visualize the mesh connectivity with global and local DOF
numberings.
"""
import numpy as nm

import matplotlib.pyplot as plt

def _get_axes(ax, dim):
if ax is None:
fig = plt.figure()
if dim == 3:
from mpl_toolkits.mplot3d import axes3d
axes3d # Make pyflakes happy...

else:

return ax

def _to2d(coors):
if coors.shape[1] == 1:
coors = nm.c_[coors, nm.zeros_like(coors)]

return coors

[docs]def plot_points(ax, coors, vals=None, point_size=20,
show_colorbar=False):
"""
Plot points with given coordinates, optionally colored using `vals` values.
"""
dim = coors.shape[1]
ax = _get_axes(ax, dim)

colors = 'b' if vals is None else vals

coors = _to2d(coors)
sc = ax.scatter(*coors.T, s=point_size, c=colors, alpha=1)

if show_colorbar and (vals is not None):
plt.colorbar(sc)

return ax

[docs]def plot_mesh(ax, coors, conn, edges, color='k', **plot_kwargs):
"""
Plot a finite element mesh as a wireframe.
"""
dim = coors.shape[1]
ax = _get_axes(ax, dim)
coors = _to2d(coors)

for el in conn:
eds = el[edges]

for ed in eds:
cc = coors[ed]

ax.plot(*cc.T, color=color, **plot_kwargs)

return ax

[docs]def plot_global_dofs(ax, coors, econn):
"""
Plot global DOF numbers given in an extended connectivity.

The DOF numbers are plotted for each element, so on common facets they are
plotted several times - this can be used to check the consistency of the
global DOF connectivity.
"""
dim = coors.shape[1]
ax = _get_axes(ax, dim)
coors = _to2d(coors)

for el in econn:
for gdof in el:
ax.text(*coors[gdof], s='%d' % gdof,
color='g', fontsize=12, weight='bold')

return ax

[docs]def plot_local_dofs(ax, coors, econn):
"""
Plot local DOF numbers corresponding to an extended connectivity.
"""
dim = coors.shape[1]
ax = _get_axes(ax, dim)
coors = _to2d(coors)

eps = 0.1
oeps = 1.0 - eps
for el in econn:
# Element centre.
centre = coors[el].sum(0) / el.shape[0]

for ldof, gdof in enumerate(el):
# Shift labels towards the centre.
cc = oeps * coors[gdof] + eps * centre

ax.text(*cc, s='%d' % ldof,
color='b', fontsize=10, weight='light')

return ax

[docs]def plot_nodes(ax, coors, econn, ref_nodes, dofs):
"""
Plot Lagrange reference element nodes corresponding to global DOF numbers
given in an extended connectivity.
"""
dim = coors.shape[1]
ax = _get_axes(ax, dim)
coors = _to2d(coors)

eps = 0.2
oeps = 1.0 - eps
for el in econn:
# Element centre.
centre = coors[el].sum(0) / el.shape[0]

for gdof in dofs:
if not gdof in el:
continue
ldof = nm.where(el == gdof)[0]
node = ref_nodes[ldof]

# Shift labels towards the centre.
cc = oeps * coors[gdof] + eps * centre

ax.text(*cc, s='%s' % node,
color='r', fontsize=8, weight='light')

return ax
```