# HG changeset patch
# User Chris Cannam
# Date 1382698235 -3600
# Node ID b3106795bbbfa0be553483adecd8fdcdbc0959c6
# Parent  2e87f815f5bcdec64ed3043cd379e6e8c8122771
Fix and test complex fft

diff -r 2e87f815f5bc -r b3106795bbbf src/may/transform/fft.yeti
--- a/src/may/transform/fft.yeti	Fri Oct 25 11:50:16 2013 +0100
+++ b/src/may/transform/fft.yeti	Fri Oct 25 11:50:35 2013 +0100
@@ -5,6 +5,7 @@
 
 vec = load may.vector;
 complex = load may.complex;
+bf = load may.vector.blockfuncs;
 
 load may.complex.type;
 
@@ -33,21 +34,18 @@
     v);
 
 unpackedToComplex len unp is number -> ~double[] -> array<cplx> =
-    array
-       (map2 complex.complex
-           (vec.list (vec.slice unp 0 len))
-           (vec.list (vec.slice unp len (len*2))));
+   (vv = bf.unzipped 2 unp;
+    array (map2 complex.complex (vec.list vv[0]) (vec.list vv[1])));
 
-complexToUnpacked len cc is number -> array<cplx> -> ~double[] =
-    vec.primitive
-       (vec.resizedTo (len*2)
-           (vec.fromList (map complex.real cc ++ map complex.imaginary cc)));
+complexToUnpacked cc is array<cplx> -> ~double[] =
+    bf.zipped [ vec.fromList (map complex.real cc),
+                vec.fromList (map complex.imaginary cc) ];
 
 //!!! doc: n separately as below
 forward n =
    (d = new DoubleFFT_1D(n);
     do cc:
-        arr = complexToUnpacked n cc;
+        arr = vec.resizedTo (n*2) (complexToUnpacked cc);
         d#complexForward(arr);
         unpackedToComplex n arr;
     done);
@@ -56,7 +54,7 @@
 inverse n =
    (d = new DoubleFFT_1D(n);
     do cc:
-        arr = complexToUnpacked n cc;
+        arr = vec.resizedTo (n*2) (complexToUnpacked cc);
         d#complexInverse(arr, true);
         unpackedToComplex n arr;
     done);
@@ -67,7 +65,7 @@
 realForward n = 
    (d = new DoubleFFT_1D(n);
     do bl:
-        v = vec.primitive (vec.resizedTo n bl);
+        v = vec.resizedTo n bl;
         d#realForward(v);
         packedToComplex n v;
     done);
diff -r 2e87f815f5bc -r b3106795bbbf src/may/transform/test/test_fft.yeti
--- a/src/may/transform/test/test_fft.yeti	Fri Oct 25 11:50:16 2013 +0100
+++ b/src/may/transform/test/test_fft.yeti	Fri Oct 25 11:50:35 2013 +0100
@@ -1,9 +1,9 @@
 
 module may.transform.test.test_fft;
 
-{ realForward, realForwardMagnitude, realInverse } = load may.transform.fft;
+{ forward, inverse, realForward, realForwardMagnitude, realInverse } = load may.transform.fft;
 { list, fromList } = load may.vector;
-{ complex, magnitude } = load may.complex;
+{ complex, magnitude, real, imaginary } = load may.complex;
 
 { compare } = load may.test.test;
 
@@ -17,10 +17,17 @@
                                reals imags)
     );
 
+testFFTComplex rin iin rout iout =
+   (cin = array (map2 complex rin iin);
+    cout = forward (length cin) cin;
+    back = inverse (length cin) cout;
+    compare (map real cout) rout and
+        compare (map imaginary cout) iout and
+        compare back cin
+    );
+
 [
 
-//!!! test complex forward/inverse
-
 "dc": \(
     testFFT [1,1,1,1] [4,0,0] [0,0,0];
 ),
@@ -48,6 +55,18 @@
         testFFT [0,0,0,1] [1,0,-1] [0,1,0];
 ),
 
+"c_dc": \(
+    testFFTComplex [1,1,1,1] [1,1,1,1] [4,0,0,0] [4,0,0,0];
+),
+
+"c_cosine": \(
+    testFFTComplex [1,0,-1,0] [1,0,-1,0] [0,2,0,2] [0,2,0,2];
+),
+
+"c_sineCosine": \(
+    testFFTComplex [1,0,-1,0] [0,1,0,-1] [0,4,0,0] [0,0,0,0];
+),
+
 ] is hash<string, () -> boolean>;