Scale function in Spin

jdolecki

Arduino has a scale function to scale data

val = map(val, 0, 1023, 0, 179); // scale it to use it with the servo (value between 0 and 180)

How do i do this in spin?

SRLM

Take a look at the source:

long map(long x, long in_min, long in_max, long out_min, long out_max)
{
  return (x - in_min) * (out_max - out_min) / (in_max - in_min) + out_min;
}

If you assume that the minimum of the ranges are always 0 then you can simplify:

long map(long x, long in_max, long out_max)
{
  return (x) * (out_max) / (in_max);
}

Beau Schwabe

Here is a Spin PUB function which takes a similar approach to SRLM's version

pub map(_val,lowIN,highIN,lowOUT,highOUT)|deltaIN,deltaOUT
    deltaIN  := highIN-lowIN
    deltaOUT := highOUT-lowOUT
    result := ((deltaOUT * (_val-lowIN)) / deltaIN)+lowOUT