robtillaart:
would be better...
put this in a file multiMap.h and use it as a library
#include "Arduino.h"
template
T multiMap(T val, T* _in, T* _out, uint8_t size)
{
// take care the value is within range
// val = constrain(val, _in[0], _in[size-1]);
if (val <= _in[0]) return _out[0];
if (val >= _in[size-1]) return _out[size-1];
// search right interval
uint8_t pos = 1; // _in[0] allready tested
while(val > _in[pos]) pos++;
// this will handle all exact "points" in the _in array
if (val == _in[pos]) return _out[pos];
// interpolate in the right segment for the rest
return (val - _in[pos-1]) * (_out[pos] - _out[pos-1]) / (_in[pos] - _in[pos-1]) + _out[pos-1];
}
demo sketch
#include "multiMap.h"
int in[] = {
11,22,33};
int out[] = {
111,222,555};
float fin[] = {
11,22,33};
float fout[] = {
111,222,555};
uint32_t start;
uint32_t stop;
void setup()
{
Serial.begin(115200);
Serial.println("Start ");
start = micros();
float x = multiMap(12, in, out, 3);
stop = micros();
Serial.println(stop-start);
Serial.println(x);
start = micros();
float y = multiMap(12, fin, fout, 3);
stop = micros();
Serial.println(stop-start);
Serial.println(y);
}
void loop() {}
disclaimer, not tested extensively.
