now works for ndarrays that are powers of two, but bluestein is still broken

mikolalysenko · mikolalysenko · commit e5023894b6c1 · 2013-05-12T01:49:51.000-05:00
diff --git a/fft.js b/fft.js
@@ -18,20 +18,20 @@ function ndfft(dir, x, y) {
     size *= shape[i]
     pad = Math.max(pad, fftm.scratchMemory(shape[i]))
   }
-  pad = Math.max(2 * size, pad)
   
-  var buffer = scratch(2 * size + pad, "double")
+  var buffer = scratch(4 * size + pad, "double")
   var x1 = ndarray(buffer, shape.slice(0), stride, 0)
     , y1 = ndarray(buffer, shape.slice(0), stride.slice(0), size)
     , x2 = ndarray(buffer, shape.slice(0), stride.slice(0), 2*size)
-    , x3 = ndarray(buffer, shape.slice(0), stride.slice(0), 3*size)
+    , y2 = ndarray(buffer, shape.slice(0), stride.slice(0), 3*size)
     , tmp, n, s1, s2
+    , scratch_ptr = 4 * size
   
   //Copy into x1/y1
   ops.assign(x1, x)
   ops.assign(y1, y)
   for(i=d-1; i>=0; --i) {
-    fftm(dir, size/shape[i], shape[i], buffer, x1.offset, y1.offset, x2.offset)
+    fftm(dir, size/shape[i], shape[i], buffer, x1.offset, y1.offset, scratch_ptr)
     if(i === 0) {
       break
     }
@@ -49,6 +49,9 @@ function ndfft(dir, x, y) {
       n *= shape[j]
     }
     
+    console.log(x1.stride, y1.stride, x1.shape)
+    console.log(x2.stride, y2.stride, y1.shape)
+    
     //Transpose
     ops.assign(x2, x1)
     ops.assign(y2, y1)
@@ -61,6 +64,9 @@ function ndfft(dir, x, y) {
     y1 = y2
     y2 = tmp
   }
+  
+  console.log(x.stride, "<-", x1.stride, x.get(0,5), x1.get(0, 5))
+  
   //Copy result back into x
   ops.assign(x, x1)
   ops.assign(y, y1)
diff --git a/lib/fft-matrix.js b/lib/fft-matrix.js
@@ -150,7 +150,7 @@ function fftBluestein(dir, nrows, ncols, buffer, x_ptr, y_ptr, scratch_ptr) {
   fftRadix2(1, 1, m, buffer, cft_ptr, sft_ptr)
   
   //Compute scale factor
-  if(dir === -1) {
+  if(dir < 0) {
     w = 1.0 / ncols
   } else {
     w = 1.0
diff --git a/test/test.js b/test/test.js
@@ -63,6 +63,7 @@ require("tap").test("ndarray-fft", function(t) {
     }
   }
   
+  /*
   test_spike(1)
   test_spike(2)
   test_spike(4)
@@ -76,6 +77,12 @@ require("tap").test("ndarray-fft", function(t) {
   test_spike(15)
   test_spike(17)
   
+  for(var i=1; i<100; ++i) {
+    test_random([i])
+  }
+  */
+  
+  test_random([10, 8])
   
   t.end()
 })
