I am getting an **“unknown name”** semantic error on the **clamp()** function in the .cantabileControlCurve file I am developing. The expression is:

```
"scalarToPosition(x)": "clamp( ((log(x,10)*20 >= -6) ? ((log(x,10)*20 + 26.8235294118) * 31.1666666641) : (826 - Sqrt(-34869 - 220660*log(x,10)))) / 1023, 0, 1)",
```

*(This relates to my development of control curves that match TotalMix.)*

The error occurs when I start up Cantabile (which apparently parses all available .cantabileControlCurve files in the Resources directory on launch):

I’m looking at the function reference at https://www.cantabilesoftware.com/guides/functions.

**When I remove the clamp() call the expression parses and Cantabile implements the new control curves as expected.**

Not sure if this is an @brad question, or whether I’ve misunderstood control expressions.