np.argmax(array, axis)

np.argmax()这个函数返回的就是数组array中最大值的索引值.

argmax(a, axis=None, out=None)
    Returns the indices of the maximum values along an axis.           
    #返回向量的最大值的索引
 
    Parameters
    ----------
    a : array_like
        Input array.
    axis : int, optional
        By default, the index is into the flattened array, otherwise
        along the specified axis.
    out : array, optional
        If provided, the result will be inserted into this array. It should
        be of the appropriate shape and dtype.

函数用法

1、一维数组

In :       	a = np.array([3,1,2,1,3,5])
Out: 		[3,1,2,1,3,5]
 
In : 		b = np.argmax(a)                        # 元素最大值的索引值      
Out: 		5    

2、二维数组

In :       	a = np.array([[1, 3, 5, 7],[5, 7, 2, 2],[4, 6, 8, 1]])
Out: 		[[1, 3, 5, 7],
                [5, 7, 2, 2],
                [4, 6, 8, 1]]
 
In : 		b = np.argmax(a, axis=0)						# 对数组按列方向搜索最大值                           
Out: 		[1 1 2 0]       
 
In : 		b = np.argmax(a, axis=1)						# 对数组按行方向搜索最大值                           
Out: 		[3 1 2]