init

FOTF Toolbox/num_diff.m

@@ -0,0 +1,13 @@
+function [f,t]=num_diff(y,h,n,p)
+% num_diff integer-order numerical differentiation
+
+% Copyright (c) Dingyu Xue, Northeastern University, China
+% Last modified 18 May, 2022 
+   arguments, y(:,1), h(1,1) {mustBePositive}
+      n(1,1){mustBeInteger,mustBePositive}
+      p(1,1){mustBeInteger,mustBePositive}
+   end
+   m=n+p; alpha=0:m; c=double(fdcoef(n,m,alpha)); 
+   t=(0:length(y)-m)'*h; 
+   for i=1:length(y)-m+1, yy=y(i:i+m-1); f(i,1)=c*yy/h^n; end
+end