DSP - Cross Correlation (Scilab Code with Plot)

Scilab Code:

//Cross-correlation of x(n) and h(n) is:

//R(k) = summation of x(n).h(n-k) for n = -INF to INF

//Positions of origin in given sequences don't matter,

//they're taken only for plotting the given sequences.

clc; clear; close;

x = input("Enter First Sequence: ");

h = input("Enter Second Sequence: ");

x_origin = input("Enter the origin position in first sequence: ");

h_origin = input("Enter the origin position in second sequence: ");

x_upper = length(x) - x_origin;

h_upper = length(h) - h_origin;

x_lower = -(x_origin - 1);

h_lower = -(h_origin - 1);

//Plot x(n)

subplot(3,1, 1);

n = x_lower : x_upper;

plot2d3(n, x, style=color("red"));

xtitle("x(n)","n");

a = gca();

a.x_location = "origin";

a.y_location = "origin";

a.children.children(1).thickness = 2;

//Plot h(n)

subplot(3,1, 2);

n = h_lower : h_upper;

plot2d3(n, h, style=color("green"));

xtitle("h(n)","n");

a = gca();

a.x_location = "origin";

a.y_location = "origin";

a.children.children(1).thickness = 2;

//Plot the cross correlation

subplot(3,1, 3);

[y, ind] = xcorr(x, h);

disp(y, "Cross correlation  = ");

plot2d3(ind, y, style=color("blue"));

a = gca();

a.y_location = "origin";

xtitle("Cross Correlation of x(n) and h(n)","n","R(k)");

a.children.children(1).thickness = 2;

Console I/O:

Plot: