I hope this helps. I’ve always had a hard time with matplotlib’s dates. Matplotlib requires a float format which is days since epoch. The helper functions num2date and date2num along with python builtin datetime can be used to convert to/from. The formatting business was lifted from this example. You can change an axis on any … Read more
Using the new pandas release (0.14.0 or later) the below code will work. To create the two axis I have manually created two matplotlib axes objects (ax and ax2) which will serve for both bar plots. When plotting a Dataframe you can choose the axes object using ax=…. Also in order to prevent the two … Read more
Actually both linked questions provide a way how to achieve the desired result. The easiest method is to create as many scatter plots as unique classes exist and give each a single color and legend entry. import matplotlib.pyplot as plt x=[1,2,3,4] y=[5,6,7,8] classes = [2,4,4,2] unique = list(set(classes)) colors = [plt.cm.jet(float(i)/max(unique)) for i in unique] … Read more
To plot multiple graphs on the same figure you will have to do: from numpy import * import math import matplotlib.pyplot as plt t = linspace(0, 2*math.pi, 400) a = sin(t) b = cos(t) c = a + b plt.plot(t, a, ‘r’) # plotting t, a separately plt.plot(t, b, ‘b’) # plotting t, b separately … Read more
The plt.tick_params method is very useful for stuff like this. This code turns off major and minor ticks and removes the labels from the x-axis. Note that there is also ax.tick_params for matplotlib.axes.Axes objects. from matplotlib import pyplot as plt plt.plot(range(10)) plt.tick_params( axis=”x”, # changes apply to the x-axis which=”both”, # both major and minor … Read more
They all do different things, since matplotlib uses a hierarchical order in which a figure window contains a figure which may consist of many axes. Additionally, there are functions from the pyplot interface and there are methods on the Figure class. I will discuss both cases below. pyplot interface pyplot is a module that collects … Read more
When using matplotlib.pyplot.savefig, the file format can be specified by the extension: from matplotlib import pyplot as plt plt.savefig(‘foo.png’) plt.savefig(‘foo.pdf’) That gives a rasterized or vectorized output respectively. In addition, there is sometimes undesirable whitespace around the image, which can be removed with: plt.savefig(‘foo.png’, bbox_inches=”tight”) Note that if showing the plot, plt.show() should follow plt.savefig(); … Read more
Abritrary points can be supplied as 1D arrays to matplotlib.Axes3D.plot_trisurf. It doesn’t matter whether they follow a specific structure. Other methods which would depend on the structure of the data would be Interpolate the points on a regular rectangular grid. This can be accomplished using scipy.interpolate.griddata. See example here Reshape the input arrays such that … Read more