@Aditya Gandhi: in general interpolation will not work, e.g. as shown in all the completely nonsensical answers below. Your independent variables are RPM and throttle, the function of those two variables is torque. Importantly, the torque function is non-monotonic (it increases and then decreases with RPM).
Now you have torque and RPM values, and you want to identify the corresponding throttle angle: this means you have a function value and one independent variable, and you are trying to obtain the value of the other independent variable.
In general there is no simple way to solve this problem. Note that there can be zero, one, a finite number, or infinite values of that independent variable that produce that function value. This I already explained to you:
In the same comment I also gave you an approach you could use to start investigating this. This you have ignored.
You keep trying to interpolate different permutations of the data, hoping that one of them will magically interpolate. It won't.
A much better use of your time would be to
- understand the problem (which would also show you why interpolation does not work)
- investigate appropriate solutions (e.g. contour algorithms, joining closest points, etc)
Note that in some limited circumstances (e.g. you take a subset of the function which is monotonic) you might be able to use interpolation, but this would a) not be a general solution, b) take some effort to isolate the required domain (if at all possible).
