# defining multivariate piecewise function

I need to define some function like `f(x,y) = x * sin(y)/y if y != 0, x otherwise`

, such that `f`

can be differentiated. Is there a way to do so? Thanks!

defining multivariate piecewise function

`f(x,y) = x * sin(y)/y if y != 0, x otherwise`

, such that `f`

can be differentiated. Is there a way to do so? Thanks!

add a comment

1

`piecewise`

currently only supports a single variable, but in your case you could factor out the `x`

and define

```
f(x,y) = x * piecewise([[(-oo,0), sin(y)/y], [[0,0], 1], [(0,oo), sin(y)/y]])
```

The square brackets around the origin denote a closed domain to ensure that point is included.

Asked: **
2017-02-11 07:24:14 -0500
**

Seen: **41 times**

Last updated: **Feb 11**

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