将数组转换为矩阵，其元素填充 Tensorflow 中矩阵的上三角形

Question

我想通过以下方式之一将数组转换为填充矩阵上三角形的矩阵

在tf.contrib.distributions.fill_triangular中，三角矩阵元素以顺时针螺旋方式填充，包括对角线元素。我尝试了以下一组命令，但没有奏效。

x = placeholder(tf.float32, shape=[None, 891])
dummy_expected_output = placeholder(tf.float32, shape=[None, 42, 42])
ones = tf.ones_like(dummy_expected_output) #size of the output matrix 
mask_a = tf.matrix_band_part(ones, 0, -1)  # Upper triangular matrix of 0s and 1s
mask_b = tf.matrix_band_part(ones, 0, 0)  # Diagonal matrix of 0s and 1s
mask = tf.subtract(mask_a, mask_b) # Mask of upper triangle above diagonal
zero = tf.constant(0, dtype=tf.float32)
non_zero = tf.not_equal(ones, zero) #Conversion of mask to Boolean matrix

indices = tf.cast(tf.where(non_zero),dtype=tf.int64) # Extracting the indices of upper triangle elements

zeros = tf.zeros_like(dummy_expected_output) #size of the output matrix
out = tf.add(zeros, tf.sparse_to_dense(indices,tf.cast(tf.shape(zeros),dtype=tf.int64), tf.reshape(x,[-1]), default_value=0))

导致错误“无法将类型对象转换为张量。内容：[无]。考虑将元素转换为支持的类型”。我尝试铸造，但没有奏效。谁能帮帮我？

Answer 1

您的输出模式之一是通过稍微重构代码获得的。

sess = tf.InteractiveSession()
x = tf.constant([1, 2, 3, 4, 5, 6])
ones = tf.ones((4,4),dtype=tf.int64) #size of the output matrix
mask_a = tf.matrix_band_part(ones, 0, -1)  # Upper triangular matrix of 0s and 1s
mask_b = tf.matrix_band_part(ones, 0, 0)  # Diagonal matrix of 0s and 1s
mask = tf.subtract(mask_a, mask_b) # Mask of upper triangle above diagonal

zero = tf.constant(0, dtype=tf.int64)
non_zero = tf.not_equal(mask, zero) #Conversion of mask to Boolean matrix
sess.run(non_zero)
indices = tf.where(non_zero) # Extracting the indices of upper trainagle elements

out = tf.SparseTensor(indices,x,dense_shape=tf.cast((4,4),dtype=tf.int64))
dense = tf.sparse_tensor_to_dense(out)
dense = tf.print(dense, [dense], summarize=100)
sess.run(dense)

输出是这样的。

[[0 1 2 3]
 [0 0 4 5]
 [0 0 0 6]
 [0 0 0 0]]