testspline.m

Interpolation routines in matlab

%
% Cubic Spline Interpolation
%

clear;

n = 4;
x = [ 0.1; 0.2; 0.3; 0.4];
f = [ -0.6205; -0.2839; 0.0066; 0.2484];
z = [ 0.25 ];
fpa = 4;
fpb = 2;


% Compute free cubic spline

[a, b, c, d, iflag] = cfspline( x, f );

table(1:n-1,1) = a(1:n-1)';
table(1:n-1,2) = b(1:n-1)';
table(1:n-1,3) = c(1:n-1)';
table(1:n-1,4) = d(1:n-1)';
disp(' coefficients of free cubic spline ')
disp( '      a(i)      b(i)      c(i)      d(i) ' )
disp(table)

s = csplineeval( x, a, b, c, d, z )



% Compute clamped cubic spline

[a, b, c, d, iflag] = ccspline( x, f, fpa, fpb );

table(1:n-1,1) = a(1:n-1)';
table(1:n-1,2) = b(1:n-1)';
table(1:n-1,3) = c(1:n-1)';
table(1:n-1,4) = d(1:n-1)';
disp(' coefficients of clamped cubic spline ')
disp( '      a(i)      b(i)      c(i)      d(i) ' )
disp(table)

s = csplineeval( x, a, b, c, d, z )