4.3. Plotting outputs in 3d: 2d histograms

4.3.1. 2d histograms

2d histograms as in example may be plotted in 3d. Three methods are provided for this purpose. All the methods support the same extra options as matshow.

4.3.1.1. Surface

The method plot_surface is using plot_surface(X, Y, Z, …) matplotlib function passing output data as X, Y and Z.

06_hist2d_plot3d.py

import gna.constructors as C
import numpy as np
from gna.bindings import common
from matplotlib import pyplot as plt
# Create numpy array for data points
xmin, ymin = 10, 20
nbinsx, nbinsy = 40, 50
edgesx = np.linspace(xmin, xmin+nbinsx*0.5, nbinsx+1)**2
edgesy = np.linspace(ymin, ymin+nbinsy*0.5, nbinsy+1)**0.25
# Create fake data array
cx = (edgesx[1:] + edgesx[:-1])*0.5
cy = (edgesy[1:] + edgesy[:-1])*0.5
X, Y = np.meshgrid(cx, cy, indexing='ij')
narray = np.exp(-0.5*(X-cx[15])**2/150.0**2 - 0.5*(Y-cy[20])**2/0.10**2)

# Create a histogram instance with data, stored in `narray`
# and edges, stored in `edges`
hist = C.Histogram2d(edgesx, edgesy, narray)

from mpl_toolkits.mplot3d import Axes3D

fig = plt.figure()
ax = plt.subplot( 111, projection='3d' )
ax.set_title( 'surface' )
ax.minorticks_on()
ax.set_xlabel( 'x label' )
ax.set_ylabel( 'y label' )

hist.hist.hist.plot_surface(cmap='viridis', colorbar=True)

plt.show()

In order the surface was colorized cmap option should be passed with a valid colormap name (use viridis).

2d histogram, plotted via plot_surface() method.

Note

Note that mplot3d toolkit should be used (line 20) and the projection='3d' option should be set for a subplot (line 23).

4.3.1.2. 3d bars

The method plot_bar3d is using bar3d(X, Y, Z, dX, dY, dZ, …) matplotlib function passing output data as X, Y, Z, dX, dY, dZ.

By default the bars are not colorized: cmap=True may be used to colorize the bars with default colormap.

06_hist2d_plot3d.py

hist.hist.hist.plot_bar3d(cmap=True, colorbar=True)

2d histogram, plotted via plot_bar3d() method.

4.3.1.3. Wireframe

The method plot_wireframe is using plot_wireframe(X, Y, Z, …) matplotlib function passing output data as X, Y, and Z.

By default wire frame is not colorized: cmap=True may be used to colorize the wires with default colormap.

06_hist2d_plot3d.py

hist.hist.hist.plot_wireframe(cmap=True, colorbar=True)

2d histogram, plotted via plot_wireframe() method.