Hi everybody,

I have a problem regarding data processing in python. Assuming we have two sets of data (x1, y1 and x2, y2), both have different points and spacing. For example:

```
x1=[4, 3, 2.5, 2, 1, -1, -1.5, -2, -4]
y1=[1, 0.8, 0.7, 0.5, 0.3, 0, -0.3, -0.6, -0.9]
x2=[5, 3, 2, 1, -1, -1.5, -5]
y2=[2, 1.8, 1, 0, 0.2, -0.5, -1.5, 2.5]
```

How to subtract `y1 `

from `y2`

?

```
y3=y2-y1
```

So far I have tried to use interpolate to first get `y1_new`

, which represents `y1`

in `x2`

:

```
y1_new = y1 = np.interp(x2,x1,y1)
```

Thanks in advance.