一、总述:
NumPy的基础,方便查阅。
...[[0,2],[0,4],[5,6]]
x[:2,:1] = [[8],[6]] # 用数组赋值
print(x) # [[8,2],[6,4],[5,6]]
六、ndarray数组的布尔索引和其他索引...(cond,-2,2)
print(x) # [-2 2 -2 2]
cond = numpy.array([1,2,3,4])
x = numpy.where(cond>2,-2,2)
...print(x) # [ 2 2 -2 -2]
y1 = numpy.array([-1,-2,-3,-4])
y2 = numpy.array([1,2,3,4])
x = numpy.where...(cond>5,y3,numpy.where(cond>2,y1,y2))
print(x) # [ 1. 2. -3. -4. -5. 0.]