CUMSIM: "CUMulative SIMpson" integral

CUMSIM integrates sampled vectors or matrices y as functions of vector x, not necessarily uniform. Parabolic interpolation is made by PARFIL.

Contents of CUMSIM.zip

CUMSIM
CUMSPLINE
COMPCUM

CUMSPLINE: similar to CUMSIM, but interpolation is made by interp1(x,y,X,'spline'), where X=parfil(x,x);

COMPCUM: compares results of

CUMSIM,
CUMSIMPSON (cf. FEX) and
CUMSPLINE,

integrating sin(x) with randomly generated x.
Repetitive call of COMPCUM generates different versions of the screenshot above.

As a rule, CUMSPLINE wins, but if the data are slightly noisy, CUMSIM can win (cf. PARFIL).