---
title: If-else branching
---

# #19. If-else branching

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To get a better learning experience we recommend to install the
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All the comparison nodes return true or false.

Let's imagine that you need to turn the servo to a certain angle, for instance
to 45° when you receive true, and to 135° when you receive false. How can we
make that work?

There is an `if-else` node in `xod/core`. The `COND` pin of this node checks
the boolean input value. If `COND` receives true, the node sets the value
from the `T` pin to the `R` pin. When it receives false, it sets the value
from the `F` pin to the `R` pin.

![Patch](./patch.png)

Now simply set the `T` value to 0.25 and the `F` value to 0.75 to make things
work.

## Test circuit

![Circuit](./circuit.fz.png)

[↓ Download as a Fritzing project](./circuit.fzz)

Now, if the comparison condition is true, the servo will turn to the angle from
the `T` pin of the `if-else` node or, otherwise, to the angle set in the `F`
pin of the same node.

[Next lesson →](../20-fade/)