diff mononomial.m @ 820:501750fbbfdb

Merge with feature/grids
author Jonatan Werpers <jonatan@werpers.com>
date Fri, 07 Sep 2018 14:40:58 +0200
parents 0090a86d8b72
children
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mononomial.m	Fri Sep 07 14:40:58 2018 +0200
@@ -0,0 +1,17 @@
+% calculate a N-D mononomial with powers k in points x:
+%  z = x(:,1).^k(1) * x(:,2).^k(2) * ...
+function z = mononomial(x, k)
+    assert(size(x,2) == length(k), 'k must have the same length as the width of x');
+
+    if any(k < 0)
+        z = x(:,1)*0;
+        return
+    end
+
+    denom = prod(factorial(k));
+
+    for i = 1:length(k)
+        x(:,i) = x(:,i).^k(i);
+    end
+    z = prod(x,2)/denom;
+end