# HG changeset patch
# User Chris Cannam
# Date 1367518148 -3600
# Node ID 344f0fefa00cc1eb42597fd83e0b3c9561b6f356
# Parent  ec43e528464be717f129d4f9fe48b8fe0ab5694e
Implement and test delayedBy

diff -r ec43e528464b -r 344f0fefa00c yetilab/stream/filter.yeti
--- a/yetilab/stream/filter.yeti	Thu May 02 19:09:01 2013 +0100
+++ b/yetilab/stream/filter.yeti	Thu May 02 19:09:08 2013 +0100
@@ -2,6 +2,7 @@
 module yetilab.stream.filter;
 
 mat = load yetilab.matrix.matrix;
+bl = load yetilab.block.block;
 
 load yetilab.stream.streamtype;
 
@@ -41,6 +42,38 @@
         close = s.close,
     };
 
+delayedBy nsamples s = //!!! should nsamples be a time in seconds?
+   (var prepos = 0;
+    delay = nsamples;
+    zeros n = 
+       (prepos := prepos + n;
+        mat.zeroMatrix { rows = s.channels, columns = n });
+    glueMatrices m1 m2 =
+        mat.newMatrix (RowMajor ())
+           (map2 do row1 row2: bl.concat [ row1, row2 ] done 
+               (mat.asRows m1) (mat.asRows m2));
+    {
+        get position () = 
+            if prepos < delay then prepos else s.position + delay fi,
+        get channels () = s.channels,
+        get sampleRate () = s.sampleRate,
+        get available () = 
+            case s.available of 
+            Known a: Known (a + delay - prepos); 
+            other: other 
+            esac,
+        get finished? () = (prepos >= delay) and s.finished?,
+        read count =
+            if prepos >= delay then s.read count
+            elif prepos + count < delay then zeros count
+            else
+                nleft = delay - prepos;
+                left = zeros nleft;
+                right = s.read (count - nleft);
+                glueMatrices left right;
+            fi,
+        close = s.close
+    });
 
 //!!! not really mixed -- what's the word for it? one per channel
 mixed s1 s2 = //!!! could generalise to list of streams
@@ -64,6 +97,7 @@
 
 {
     truncatedTo, 
+    delayedBy,
     mixed,
 //!!!} as {
 //    truncatedTo is number -> stream -> stream
diff -r ec43e528464b -r 344f0fefa00c yetilab/stream/test/test_filter.yeti
--- a/yetilab/stream/test/test_filter.yeti	Thu May 02 19:09:01 2013 +0100
+++ b/yetilab/stream/test/test_filter.yeti	Thu May 02 19:09:08 2013 +0100
@@ -20,6 +20,91 @@
         compare str.finished? false and
         compare (bl.list ((str.read 4).getRow 0)) [ 0, 0.5, 1 ] and
         compare str.position 3 and
+        compare str.available (Known 0) and
+        compare str.finished? true and
+        ( str.close (); true )
+),
+
+"delayedBy-0-3": \(
+    str = filt.delayedBy 0 (filt.truncatedTo 3 (syn.generated 2 id));
+    compare str.position 0 and
+        compare str.channels 1 and
+        compare str.sampleRate 2 and
+        compare str.available (Known 3) and
+        compare str.finished? false and
+        compare (bl.list ((str.read 4).getRow 0)) [ 0, 0.5, 1 ] and
+        compare str.position 3 and
+        compare str.available (Known 0) and
+        compare str.finished? true and
+        ( str.close (); true )
+),
+
+"delayedBy-0-inf": \(
+    str = filt.delayedBy 0 (syn.generated 2 id);
+    compare str.position 0 and
+        compare str.channels 1 and
+        compare str.sampleRate 2 and
+        compare str.available (Infinite ()) and
+        compare str.finished? false and
+        compare (bl.list ((str.read 4).getRow 0)) [ 0, 0.5, 1, 1.5 ] and
+        compare str.position 4 and
+        compare str.available (Infinite ()) and
+        compare str.finished? false and
+        ( str.close (); true )
+),
+
+"delayedBy-2-3": \(
+    str = filt.delayedBy 2 (filt.truncatedTo 3 (syn.generated 2 id));
+    compare str.position 0 and
+        compare str.channels 1 and
+        compare str.sampleRate 2 and
+        compare str.available (Known 5) and
+        compare str.finished? false and
+        compare (bl.list ((str.read 4).getRow 0)) [ 0, 0, 0, 0.5 ] and
+        compare str.position 4 and
+        compare str.available (Known 1) and
+        compare str.finished? false and
+        compare (bl.list ((str.read 4).getRow 0)) [ 1 ] and
+        compare str.position 5 and
+        compare str.available (Known 0) and
+        compare str.finished? true and
+        ( str.close (); true )
+),
+
+"delayedBy-2-3b": \(
+    str = filt.delayedBy 2 (filt.truncatedTo 3 (syn.generated 2 id));
+    compare str.position 0 and
+        compare str.channels 1 and
+        compare str.sampleRate 2 and
+        compare str.available (Known 5) and
+        compare str.finished? false and
+        compare (bl.list ((str.read 0).getRow 0)) [ ] and
+        compare str.position 0 and
+        compare str.available (Known 5) and
+        compare str.finished? false and
+        compare (bl.list ((str.read 5).getRow 0)) [ 0, 0, 0, 0.5, 1 ] and
+        compare str.position 5 and
+        compare str.available (Known 0) and
+        compare str.finished? true and
+        ( str.close (); true )
+),
+
+"delayedBy-2-inf": \(
+    str = filt.delayedBy 2 (syn.generated 2 id);
+    compare str.position 0 and
+        compare str.channels 1 and
+        compare str.sampleRate 2 and
+        compare str.available (Infinite ()) and
+        compare str.finished? false and
+        compare (bl.list ((str.read 2).getRow 0)) [ 0, 0 ] and
+        compare str.position 2 and
+        compare str.finished? false and
+        compare (bl.list ((str.read 2).getRow 0)) [ 0, 0.5 ] and
+        compare str.position 4 and
+        compare str.finished? false and
+        compare (bl.list ((str.read 2).getRow 0)) [ 1, 1.5 ] and
+        compare str.position 6 and
+        compare str.finished? false and
         ( str.close (); true )
 ),
 
diff -r ec43e528464b -r 344f0fefa00c yetilab/stream/test/test_framer.yeti
--- a/yetilab/stream/test/test_framer.yeti	Thu May 02 19:09:01 2013 +0100
+++ b/yetilab/stream/test/test_framer.yeti	Thu May 02 19:09:08 2013 +0100
@@ -4,8 +4,11 @@
 fr = load yetilab.stream.framer;
 block = load yetilab.block.block;
 mat = load yetilab.matrix.matrix;
+syn = load yetilab.stream.syntheticstream;
 
-{ compare, compareUsing, testStream } = load yetilab.test.test;
+{ compare, compareUsing } = load yetilab.test.test;
+
+testStream n is number -> 'a  = syn.precalculated 1000 (block.fromList [1..n]);
 
 compareFrames frames1 frames2 =
     all id (map2 do f1 f2: compareUsing mat.equal f1 f2 done frames1
diff -r ec43e528464b -r 344f0fefa00c yetilab/test/test.yeti
--- a/yetilab/test/test.yeti	Thu May 02 19:09:01 2013 +0100
+++ b/yetilab/test/test.yeti	Thu May 02 19:09:08 2013 +0100
@@ -1,14 +1,14 @@
 module yetilab.test.test;
 
 block = load yetilab.block.block;
-ss = load yetilab.stream.syntheticstream;
 
 import yeti.lang: FailureException;
 
-testStream n is number -> 'a  = ss.precalculated 1000 (block.fromList [1..n]);
+var goodCompares = 0;
 
 compareUsing comparator obtained expected =
     if comparator obtained expected then
+        goodCompares := goodCompares + 1;
         true;
     else
         println "** expected: \(expected)\n   obtained: \(obtained)";
@@ -44,6 +44,7 @@
     bad);
 
 {
-    testStream, compare, compareUsing, failedTests, runTests
+    compare, compareUsing,
+    runTests, 
 }