where¶

paddle.fluid.layers. where ( condition ) [源代码] ¶

该OP计算输入元素中为True的元素在输入中的坐标（index）。

参数¶

condition （Variable）– 输入秩至少为1的多维Tensor，数据类型是bool类型。

返回¶

输出condition元素为True的坐标（index），将所有的坐标（index）组成一个2-D的Tensor。

返回类型¶

Variable，数据类型是int64。

代码示例¶

          import paddle.fluid as fluid
import paddle.fluid.layers as layers
import numpy as np

# condition is a tensor [True, False, True]
condition = layers.assign(np.array([1, 0, 1], dtype='int32'))
condition = layers.cast(condition, 'bool')
out = layers.where(condition) # [[0], [2]]

# condition is a tensor [[True, False], [False, True]]
condition = layers.assign(np.array([[1, 0], [0, 1]], dtype='int32'))
condition = layers.cast(condition, 'bool')
out = layers.where(condition) # [[0, 0], [1, 1]]

# condition is a tensor [False, False, False]
condition = layers.assign(np.array([0, 0, 0], dtype='int32'))
condition = layers.cast(condition, 'bool')
out = layers.where(condition) # [[]]

         