added [mtx_sh] for spherical harmonics evaluation.

svn path=/trunk/externals/iem/iemmatrix/; revision=10515

1 files changed, 43 insertions, 0 deletions

diff --git a/src/mtx_sh/sharmonics.h b/src/mtx_sh/sharmonics.h
new file mode 100644
index 0000000..78919f7
--- /dev/null
+++ b/src/mtx_sh/sharmonics.h
@@ -0,0 +1,43 @@
+/*
+ * Recursive computation of (arbitrary degree) spherical harmonics, 
+ * according to Gumerov and Duraiswami,
+ * "The Fast Multipole Methods for the Helmholtz Equation in Three Dimensions",
+ * Elsevier, 2005.
+ *
+ * Implementation by Franz Zotter, Institute of Electronic Music and Acoustics
+ * (IEM), University of Music and Dramatic Arts (KUG), Graz, Austria
+ * http://iem.at/Members/zotter, 2007.
+ *
+ * This code is published under the Gnu General Public License, see
+ * "LICENSE.txt"
+ */
+
+#ifndef _sh_h__
+#define _sh_h__
+
+#include <stdlib.h>
+#include "legendre_a.h"
+#include "chebyshev12.h"
+#include "sharmonics_normalization.h"
+
+typedef struct _SHWorkSpace_
+{
+   size_t nmax;
+   size_t l;
+   
+   double *y;
+
+   SHNorml *wn;
+   Cheby12WorkSpace *wc;
+   LegendreWorkSpace *wl;
+
+} SHWorkSpace;
+
+SHWorkSpace *sharmonics_alloc(size_t nmax, size_t l);
+
+void sharmonics_free(SHWorkSpace *sh);
+
+void sharmonics(double *phi, double *theta, SHWorkSpace *ws);
+
+#endif
+