import matplotlib.pyplot as plt
import seaborn


hoge # ndarray (H,W)

fig = plt.figure()
sbplt = fig.add_subplot()
sbplt = seaborn.heatmap(hoge, vmin=0.0,vmax=1.0, annot=True, fmt='1.3f', ax=sbplt)
sbplt.figure.savefig('hoge.pdf')