Implement scalar multiple plots example for C++

[Wumpf]

What

• part of Implement missing code-examples for C++ #3751

What it says on the tin!
Tried using sin + cast instead of sinf, but still couldn't get the results to match with Rust sadly 🤷

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[emilk]

Tried using sin + cast instead of sinf, but still couldn't get the results to match with Rust sadly 🤷

We should make the comparison tool allow for a few bits of error in our floats