Physics, Data Science, Least Squares, Chemometrics, Spectroscopy.
for this case (the wavelength axis has 1000 values). So A is a vector composed of 1000 values, c is a vector composed of 3 values (the three component concentrations) and K is a 3x1000 matrix. Knowing A and K it is possible now to recalculate the 3 components concentration in the ‘unknown’ mixture: