numpy.matrix.sum#
method
- matrix.sum(axis=None, dtype=None, out=None)[源代码]#
返回给定轴上矩阵元素的和.
有关完整文档,请参阅
numpy.sum.参见
注释
这与
ndarray.sum相同,区别在于,如果返回ndarray,则返回matrix对象.示例
>>> x = np.matrix([[1, 2], [4, 3]]) >>> x.sum() 10 >>> x.sum(axis=1) matrix([[3], [7]]) >>> x.sum(axis=1, dtype='float') matrix([[3.], [7.]]) >>> out = np.zeros((2, 1), dtype='float') >>> x.sum(axis=1, dtype='float', out=np.asmatrix(out)) matrix([[3.], [7.]])