py作图

import numpy as np import matplotlib.pyplot as plt plt.rcParams['font.sans-serif'] = ['FangSong'] plt.rcParams['axes.unicode_minus'] = False xs = np.linspace(-1, 1, 11) ys = np.array([-0.3, -0.5, -0.2, -0.3, 0, 0.4, 0.2, -0.3, 0.2, 0.5, 0.4]) xm = np.linspace(-1, 1, 201) ym = ((xm**2-1)**3 + 0.5)*np.sin(2*xm) + np.random.random(201)/10 - 0.1 fs4 = np.poly1d(np.polyfit(xs, ys, 4)) fs5 = np.poly1d(np.polyfit(xs, ys, 5)) fs6 = np.poly1d(np.polyfit(xs, ys, 6)) fs7 = np.poly1d(np.polyfit(xs, ys, 7)) fs8 = np.poly1d(np.polyfit(xs, ys, 8)) fs9 = np.poly1d(np.polyfit(xs, ys, 9)) fs10 = np.poly1d(np.polyfit(xs, ys, 10)) fm2 = np.poly1d(np.polyfit(xm, ym, 2)) fm3 = np.poly1d(np.polyfit(xm, ym, 3)) fm4 = np.poly1d(np.polyfit(xm, ym, 4)) fm5 = np.poly1d(np.polyfit(xm, ym, 5)) fm6 = np.poly1d(np.polyfit(xm, ym, 6)) fm7 = np.poly1d(np.polyfit(xm, ym, 7)) plt.subplot(211) plt.plot(xs, ys, c='r', ls='', marker='o') plt.plot(xs, fs4(xs), label=u'四次多项式') plt.plot(xs, fs5(xs), label=u'五次多项式') plt.plot(xs, fs6(xs), label=u'六次多项式') plt.plot(xs, fs7(xs), label=u'七次多项式') plt.plot(xs, fs8(xs), label=u'八次多项式') plt.plot(xs, fs9(xs), label=u'九次多项式') plt.legend() plt.subplot(212) plt.plot(xm, ym, c='g', ls='', marker='.') plt.plot(xm, fm2(xm), label=u'二次多项式') plt.plot(xm, fm3(xm), label=u'三次多项式') plt.plot(xm, fm4(xm), label=u'四次多项式') plt.plot(xm, fm5(xm), label=u'五次多项式') plt.plot(xm, fm6(xm), label=u'六次多项式') plt.plot(xm, fm7(xm), label=u'七次多项式') plt.legend() plt.show()