Please help me!! how to assemble a new array with chumpy object?

[FLOWERCLOUD]

for example:
a = ch.array(5)

Rx = ch.array([[1, 0, 0],
[0, ch.cos(a), -ch.sin(a)],
[0, ch.sin(a), ch.cos(a)]])

but when I change a[0] ,the value in Rx will not change . It seems that my way of array assembly will break the forward-mode
So how can I assemble a new array and still hold the forward mode.

[tneumann]

It apparently works if you use the vstack, hstack, concatenate or reshape functions, e.g. one possibility with concatenate + reshape would be:

a = ch.array(5)
Rx = ch.concatenate([
  1, 0, 0,  
  0, ch.cos(a), -ch.sin(a),  
  0, ch.sin(a), ch.cos(a)]).reshape(3, 3)

[FLOWERCLOUD]

that works well ,thank you