How to adjust values to a new range

[Jerson]

The concept of mapping a range should be clear by this code example in C explained

// map a value(inputlow to inputhigh) to the range(outputlow to outputhigh)

int16   map(int16 val, int16 inpl, int16 inph, int16 outl, int16 outh){
int32 tmp=MAX(val,inpl)-inpl;                         // tmp = (maximum of Val and inputlow) - inputlow

    tmp *= (outh-outl);                                      // tmp = tmp * (outputhigh - outputlow)
    tmp /= (inph-inpl);                                       // tmp = tmp / (inputhigh - inputlow)
    tmp += outl;                                                // tmp = tmp + outputlow
    return MIN(tmp,outh);                                 // return the lower of tmp or outputhigh
}