#!/usr/bin/env python3
# coding: utf-8

import pylab as p

data = [
        # SolarLader, Multimeter
        [0, 0],
        [0.412, 0.388],
        [0.421, 0.392],
        [0.64,  0.591],
        [0.72,  0.655],
        [0.78,  0.705],
        [1,     0.903],
        [1.05,  0.928],
        [1.2,   1.04],
        [1.36,  1.17],
        [1.4,   1.205],
        [1.706, 1.470],
        [1.93,  1.58],
        [2,     1.661],
        [2.01,  1.683],
        [2.08,  1.69],
        [2.22,  1.78],
        [2.27,  1.815],
    ]

data_array = p.transpose(p.array(data))

Ichg = data_array[0]
Imulti = data_array[1]

adc = Ichg * 4096/8.6 + 89

fit = p.polyfit(adc, Imulti, 1)

poly = p.poly1d(fit)

#Ifit = adc**2 * fit[0] + adc * fit[1] + fit[2]
Ifit = poly(adc)
Ierror = Ifit - Imulti

adc_expanded = p.arange(0, 4095, 1)
Ifit_expanded = poly(adc_expanded)

#print("adc² • {:.3f} + adc • {:.3f} + {:.3f}".format(fit[0], fit[1], fit[2]))
print("adc • {:.3g} + {:.3g}".format(fit[0], fit[1]))

p.figure()
p.plot(adc, Imulti, 'rx')
p.plot(adc, Ifit, 'r-')
p.figure()
p.plot(adc, Imulti, 'rx')
p.plot(adc_expanded, Ifit_expanded, 'b-')
p.figure()
p.plot(adc, Ierror)
p.show()