## Issue

**I want to transform A into B:**

```
A =
[1, 1, 1]
[2]
[3, 3, 3, 3]
[4, 4]
B =
[
[0, 1, 1, 1]
[0, 0, 0, 2]
[3, 3, 3, 3]
[0, 0, 4, 4]
]
```

**Input**:

– a list of lists

**Output**:

– a single matrix or tensor

– right aligned

– Left fill with 0’s

## Solution

`A`

is a list, so we can for-loop and use `tf.pad`

and `tf.stack`

to get the output tensor.

```
max_len = max(len(e) for e in A)
res = tf.stack([tf.pad(e, [[max_len - len(e),0]]) for e in A], axis=0)
# array([[0, 1, 1, 1],
# [0, 0, 0, 2],
# [3, 3, 3, 3],
# [0, 0, 4, 4]], dtype=int32)
```

Answered By – zihaozhihao

**This Answer collected from stackoverflow, is licensed under cc by-sa 2.5 , cc by-sa 3.0 and cc by-sa 4.0 **