# How to assign matrix (vector) value to variable

when I tried to assign a matrix or a vector to variables, something wrong happens:

```
sage: sin([1,2,3,4]).n()
Traceback (click to the left of this block for traceback)
...
TypeError: cannot coerce arguments: no canonical coercion from <type
'list'> to Symbolic Ring
```

what I want to achieve is that the out put gives a vector that equals to [sin(1),sin(2),sin(3),sin(4)].

Thanks in advance!