Question

如果两个矢量可能缺少值，你如何做一个numpy dot产品？这似乎需要许多额外的步骤，有更简单的方法吗？：

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Answer 1

我们可以使用np.nansum来总结在元素乘法后忽略unescaped_str的值 -

אפרת

示例运行 -

NaNs

Answer 2

另一种解决方案是使用掩码数组：

v1 = np.array([1,4,2,np.nan,3])
v2 = np.array([np.nan,np.nan,2,4,1])

v1_m = numpy.ma.array(v1, mask=numpy.isnan(v1))
v2_m = numpy.ma.array(v2, mask=numpy.isnan(v2))

numpy.ma.dot(v1_m, v2_m)

缺少值的numpy dot产品

2 个答案: