How to construct piecewise polynomial?

I am using the following code to construct piecewise polynomial of a pascal matrix

clc
clear all
close all

% Read matrix
X=pascal(3);
disp(X);
[r c]=size(X);
i=2;
%while i==c
for j=1:c
    z=X(i,j);
    disp(z);
end
i=i+1;
%end
breaks=[0 4 10 15];
pp=mkpp(breaks,z);

Code is having error.

Answer 1

[Anurag Ojha]

Hi Avinash

The error in your code is occurring because the variable z is not defined outside the loop. To fix this, you can define z as an empty array before the loop and then append the values inside the loop.

Here's the corrected code:

clc
clear all
close all

% Read matrix
X = pascal(3);
disp(X);

     1     1     1
     1     2     3
     1     3     6

[r, c] = size(X);
i = 2;
z = []; % Initialize z as an empty array

%while i==c
for j = 1:c
    z = [z, X(i, j)]; % Append values to z
    disp(z);
end

     1

     1     2

     1     2     3

i = i + 1;
%end

breaks = [0 4 10 15];
pp = mkpp(breaks, z);

This code will construct a piecewise polynomial using the values of z obtained from the loop.