changeset 382:a519d3b7e32c

My alpha, beta are not working in emacs on Windows (pity)

--- a/may/signal/window.yeti	Fri Sep 13 14:59:27 2013 +0100
+++ b/may/signal/window.yeti	Mon Sep 16 10:53:37 2013 +0100
@@ -97,7 +97,7 @@
         vec.fromList ((take n0 (reverse half)) ++ (take n1 half));
     fi;
 
-kaiser 𝛽 n =
+kaiser beta n =
    (bes0 x = 
        (fact x = fold do x y: x*y done 1 [1..x];   // x!
         ipow a b = fold do x _: x*a done 1 [1..b]; // a^b where b∈ℕ
@@ -108,48 +108,48 @@
              _: (ipow (x/2) (i*2)) / (square (fact i));
             esac;
         sum (map (term x) [0..20]));
-    denominator = bes0 𝛽;
+    denominator = bes0 beta;
     vec.fromList
        (map do i:
             k = 2*i / (n-1) - 1;
-            bes0 (𝛽 * sqrt (1 - k*k)) / denominator;
+            bes0 (beta * sqrt (1 - k*k)) / denominator;
             done [0..n-1]));
 
 /** 
   Kaiser window with sidelobe attenuation of 𝛼 dB and window length n
 */
-kaiserForAttenuation 𝛼 n =
-   (𝛽 =
-        if 𝛼 > 50 then 0.1102 * (𝛼 - 8.7)
-        elif 𝛼 > 21 then 0.5842 * Math#pow(𝛼 - 21, 0.4) + 0.07886 * (𝛼 - 21)
+kaiserForAttenuation alpha n =
+   (beta =
+        if alpha > 50 then 0.1102 * (alpha - 8.7)
+        elif alpha > 21 then 0.5842 * Math#pow(alpha - 21, 0.4) + 0.07886 * (alpha - 21)
         else 0
         fi;
-    kaiser 𝛽 n);
+    kaiser beta n);
 
 /**
-  Kaiser window with sidelobe attenuation of 𝛼 dB and transition 
+  Kaiser window with sidelobe attenuation of alpha dB and transition 
   bandwidth of (tw * samplerate) / (2 * pi)
 */
-kaiserForTransitionLength 𝛼 tw =
-   (m = if 𝛼 > 21 
-        then Math#ceil((𝛼 - 7.95) / (2.285 * tw))
+kaiserForTransitionLength alpha tw =
+   (m = if alpha > 21 
+        then Math#ceil((alpha - 7.95) / (2.285 * tw))
         else Math#ceil(5.79 / tw)
         fi;
-    kaiserForAttenuation 𝛼 (m+1));
+    kaiserForAttenuation alpha (m+1));
 
 /**
-  Kaiser window with sidelobe attenuation of 𝛼 dB and transition
+  Kaiser window with sidelobe attenuation of alpha dB and transition
   bandwidth of tbw Hz at the given sampleRate
 */
-kaiserForBandwidth 𝛼 tbw samplerate =
-    kaiserForTransitionLength 𝛼 ((tbw * 2 * pi) / samplerate);
+kaiserForBandwidth alpha tbw samplerate =
+    kaiserForTransitionLength alpha ((tbw * 2 * pi) / samplerate);
 
 windowFunction type options =
    (var sampling = Periodic ();
-    var 𝛽 = 4;
+    var beta = 4;
     for options \case of
         Symmetric s: if s then sampling := Symmetric () fi;
-        Beta b: 𝛽 := b;
+        Beta b: beta := b;
         esac;
     case type of
     Hann (): hann sampling;
@@ -160,7 +160,7 @@
     BlackmanHarris (): blackmanHarris sampling;
     Boxcar (): boxcar;
     Bartlett (): bartlett sampling;
-    Kaiser (): kaiser 𝛽;
+    Kaiser (): kaiser beta;
     esac);
 
 //!!! should use vector. but does anyone use this function anyway? would we use it in framer if it used vector?