matplotlib 重载绘图函数

感谢 Yngve Moe 的回答，我已经设法编写了这个函数

def plot_yerr_filled(x=None, y=None, axis=plt, color=(0,0,0), alpha=0.25, *args, **kwargs):
    """Creates a 'filled error bar' plot. All keyword arguments in matplotlib functions are accepted.

    Parameters
    ----------
    x : Array like (list of float, int, etc. or numpy.array or list of magnitude) of exact 'x' values (i.e. with no error, if 'x' is a list of 'magnitude' type objects, errors are discarded).
    y : Array like (list) of 'magnitude' type elements containing the 'y' values and the 'yerr' associated error.
    axis: matplotlib.axes (optional) in which to plot the data.
    color: tuple (r,g,b) defining the color.
    alpha: float between 0 and 1 indicating the transparency of the filled error bar.
    """

    for i in range(0, len(x)): # Validation of x
        if isinstance(x[i], magnitude):
            x[i] = x[i].val
    for i in range(len(y)): # Validation of y
        if not isinstance(y[i], magnitude):
            raise ValueError('y[' + str(i) + '] is not of type "magnitude"')

    y_val = [y[i].val for i in range(len(y))]
    y_err = [y[i].err for i in range(len(y))]
    axis.fill_between(np.array(x), np.array(y_val)-np.array(y_err), np.array(y_val) + np.array(y_err), alpha=alpha, edgecolor=color, facecolor=color )
    lines = axis.plot(np.array(x), np.array(y_val), color=color, *args, **kwargs)
    return lines

这正是我想要的。这里我举个例子

import pymagpy as mg
import matplotlib.pyplot as plt
plt.rc('axes', axisbelow=True) # This is for plotting data in front of the grid.
plt.rcParams.update({'font.size': 8}) # Changes the default font size for the plots.
import numpy as np

x = mg.magnitude(1, 0.1)
y = mg.magnitude(-6798, 6)
z = mg.magnitude(1e-30, .00002872982778297289e-30)

print(x)
print(y)
print(z)
print(x+y/z*2-z/x*y) # Automatically calculates the error propagation.

x_values = []
y_values = []
z_values = []
for k in range(10):
    x_values.append(mg.magnitude(k, k**2))
    y_values.append(mg.magnitude(k**2, k))
    z_values.append(mg.magnitude(np.sqrt(300*k)+1, k/(k-2.2)+5))

FIG_WIDTH = 130e-3 # Figure width in meters (size of the chart+axis_ticks, not counting legend, title, etc.).
FIG_RATIO = [1, 0.8] # XY ratio aspect of figures.
f, (ax1, ax2) = plt.subplots(2, sharex=True, figsize=(FIG_WIDTH*FIG_RATIO[0]/25.4e-3, FIG_WIDTH*FIG_RATIO[1]/25.4e-3)) # Create the figure for plotting.
f.subplots_adjust(hspace=0.1) # Fine-tune figure; make subplots close to each other and hide x ticks for all but bottom plot.
mg.plot_yerr_filled(x_values, y_values, color=(1,0,0), alpha=.1, axis=ax1, label='Y', marker='.')
mg.plot_yerr_filled(x_values, z_values, color=(0,0,1), axis=ax1, label='Z', marker='o', linestyle='')
ax1.set_ylabel('y axis')
ax1.grid(b=True, which='major', color='#aaaaaa', linestyle='-', linewidth=0.5) # Configure the grid in a more fachera way.
ax1.grid(b=True, which='minor', color='#dddddd', linestyle='-', linewidth=0.25) # Configure the grid in a more fachera way.
ax1.minorticks_on() # Enables minor ticks without text, only the ticks.
ax1.legend(loc='best', fancybox=True, framealpha=0.7, ncol=1, fontsize=8)
mg.plot_yerr_filled(x_values, [(a*b)/(a+b) for a,b in zip(y_values, z_values)], axis=ax2, label='(Y*Z)/(Y+Z)', marker='.', linestyle='--')
ax2.set_xlabel('x axis')
ax2.set_ylabel('y axis')
ax2.grid(b=True, which='major', color='#aaaaaa', linestyle='-', linewidth=0.5) # Configure the grid in a more fachera way.
ax2.grid(b=True, which='minor', color='#dddddd', linestyle='-', linewidth=0.25) # Configure the grid in a more fachera way.
ax2.minorticks_on() # Enables minor ticks without text, only the ticks.
ax2.legend(loc='best', fancybox=True, framealpha=0.7, ncol=1, fontsize=8)
plt.savefig('example.pdf', bbox_inches='tight')
plt.show()

产生这个情节：