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diff stencilEquation.m @ 820:501750fbbfdb

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Merge with feature/grids
author Jonatan Werpers <jonatan@werpers.com>
date Fri, 07 Sep 2018 14:40:58 +0200
parents 184833fe4c0e
children
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/stencilEquation.m	Fri Sep 07 14:40:58 2018 +0200
@@ -0,0 +1,13 @@
+% Find the equation for the stencil for d^k/dx^k
+function [A,b] = stencilEquation(k, offsets, order)
+    q = sym('q', [1, length(offsets)]);
+
+    p = 0:(order-1+k);
+
+    v     = vandermonde(offsets, p);
+    vdiff = vandermonde(      0, p-k);
+
+    eq = q*v == vdiff;
+
+    [A,b] = equationsToMatrix(eq, q);
+end