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Jupyter Notebook

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构建两个x轴 [@Kington2010]

其中一个是group的性质。

```{python eval=F} import numpy as np import matplotlib.pyplot as plt import matplotlib as mpl

def annotate_group(name, xspan, ax=None): “““Annotates a span of the x-axis”” def annotate(ax, name, left, right, y, pad): arrow = ax.annotate(name, xy=(left, y), xycoords=‘data’, xytext=(right, y-pad), textcoords=‘data’, annotation_clip=False, verticalalignment=‘top’, horizontalalignment=‘center’, linespacing=2.0, arrowprops=dict(arrowstyle=’-’, shrinkA=0, shrinkB=0, connectionstyle=‘angle,angleB=90,angleA=0,rad=5’) ) return arrow if ax is None: ax = plt.gca() ymin = ax.get_ylim()[0] ypad = 0.01 * np.ptp(ax.get_ylim()) xcenter = np.mean(xspan) left_arrow = annotate(ax, name, xspan[0], xcenter, ymin, ypad) right_arrow = annotate(ax, name, xspan[1], xcenter, ymin, ypad) return left_arrow, right_arrow

def make_second_bottom_spine(ax=None, label=None, offset=0, labeloffset=20): “““Makes a second bottom spine”” if ax is None: ax = plt.gca() second_bottom = mpl.spines.Spine(ax, ‘bottom’, ax.spines[‘bottom’]._path) second_bottom.set_position((‘outward’, offset)) ax.spines[‘second_bottom’] = second_bottom

if label is not None:
    # Make a new xlabel
    ax.annotate(label,
            xy=(0.5, 0), xycoords='axes fraction',
            xytext=(0, -labeloffset), textcoords='offset points',
            verticalalignment='top', horizontalalignment='center')

#– Generate some data —————————————————- nx = 10 x = np.linspace(0, 2*np.pi, 10) y = 2 * np.sin(x)

groups = [(‘GroupA’, (x[0], x[nx//3])), (‘GroupB’, (x[-2*nx//3], x[2*nx//3])), (‘GroupC’, (x[-nx//3], x[-1]))]

#– Plot the results —————————————————— fig = plt.figure() ax = fig.add_subplot(111)

Give ourselves a bit more room at the bottom

plt.subplots_adjust(bottom=0.2)

ax.plot(x,y, ‘k^’)

Drop the bottom spine by 40 pts

ax.spines[‘bottom’].set_position((‘outward’, 40))

Make a second bottom spine in the position of the original bottom spine

make_second_bottom_spine(label=‘Treatment’)

Annotate the groups

for name, xspan in groups: annotate_group(name, xspan)

plt.xlabel(‘Dose’) plt.ylabel(‘Response’) plt.title(‘Experimental Data’)