Let say I've this sine wave (which is `sin(x * 2)`):

[![enter image description here](https://i.stack.imgur.com/arFio.png)](https://i.stack.imgur.com/arFio.png)
and I want to increase/decrese the ramp such as (sorry for my paint):

[![enter image description here](https://i.stack.imgur.com/j5DUY.png)](https://i.stack.imgur.com/j5DUY.png)
I need to multiply the argument for... what? Tried log(x) but I get strange results.