Equivalent to Max/MSP [scale]

engartst · January 18, 2021, 8:44pm

Looking for a way of scaling my data and I really like how Max does it.
aka [scale] (input-low input-high output-low output-high)

In SCAMP I have been doing:

1 fund = data['f0'] # this is reading from a JSON file
2 xmin, xmax = min(fund), max(fund) # this gets the min/max of input
3 for i, val in enumerate(fund): # normalize 
4     fund[i] = (val-xmin) / (xmax-xmin)
5 midiFund = [round(element * 30) + 50 for element in fund] 
# the first int above is the effectively the range 
# the second int is where to place that range

Anyway, it seems like this is beating around the bush quite a bit. Is there a simpler way to get desired results?

shiihs · January 19, 2021, 7:21am

You could borrow some code from someone else

E.g. if you put this file in your project and import it,

github.com

shimpe/pyvectortween/blob/master/vectortween/Mapping.py

import math


class Mapping(object):
    """
    class to map numbers from one range to another range
    """

    def _init__(self):
        pass

    @staticmethod
    def clip_value(value, minimum, maximum):
        if minimum > maximum:
            minimum, maximum = maximum, minimum
        if value < minimum:
            return minimum
        elif value > maximum:
            return maximum
        else:

This file has been truncated. show original

Then you can write e.g.

Mapping.linlin(min_in, max_in, min_out, max_out)

for linear mapping. There are also linexp, explin, and expexp for exponential or logarithmic warping during mapping.