# How to define a matrix conditional to a list of strings

Need a little help. suppose I have the following list :

```
signs=['=','=','>=','>=','>=','<=','<=','<=','<=','<=']
```

with this list I need to create in Sagemath a matrix with 10 lines and 18 columns each equality/inequality sign correspond to a line with

```
'=' gives 1 on the corresponding line the other 17 enters being 0
'>=' gives - 1, 1 on the corresponding line the other 16 enters being 0
'<=' gives 1, 1 on the corresponding line the other 16 enters being 0
```

and of course, there is only one 1 (-1) in each column.

What I want is a function. Someone will tell me that I must learn Python (smile) but each of my tentatives fails.

Thank in advance for the help