Implement schtrig.sci in Scilab

1 files changed, 125 insertions, 28 deletions

diff --git a/macros/schtrig.sci b/macros/schtrig.sci
index 90286e2..f50adca 100644
--- a/macros/schtrig.sci
+++ b/macros/schtrig.sci
@@ -1,30 +1,127 @@
-function v = schtrig (x, lev, rs)
-//This function implements a multisignal Schmitt triggers with lev levels supplied as input.
-//Calling Sequence
-//v = schtrig (x, lev)
-//v = schtrig (x, lev, rs)
-//Parameters 
-//x: vector or matrix of real numbers
-//lev: real number 
-//rs: default value 1
-//Description
-//This is an Octave function.
-//This function implements a multisignal Schmitt triggers with lev levels supplied as input.
-//The argument 1 is a matrix (or a vector) and this trigger works along its first dimension. 
-//Examples
-//schtrig([0.2,-3,5],-4)
-//ans  =
-//    0.    0.    1.  
-
-funcprot(0);
-rhs = argn(2)
-if(rhs<2 | rhs>3)
-error("Wrong number of input arguments.")
-end
-if(rhs==2)
-v = callOctave("schtrig", x, lev)
-elseif(rhs==3)
-v = callOctave("schtrig",x, lev, rs)
-end
+function [v, rg] = schtrig (x, lvl, rst)
+//This function implements a multisignal Schmitt triggers with 'lvl' levels supplied as input.
+//Calling Sequence:
+//x = schtrig(x, lvl)
+//lvl = schtrig(x, lvl, rst)
+//Parameters:
+//x: Vector or matrix of real numbers
+//lvl: Real number
+//rst: Boolean, default value is 'true'
+//Description:
+//This function implements a multisignal Schmitt triggers with 'lvl' levels supplied as input.
+//The argument 1 is a matrix (or a vector) and this trigger works along its first dimension.
+//Examples:
+//schtrig([0.2,-3,5], -4)
+//ans = [0, 0, 1]
+
+  funcprot(0);
+  warning('off');
+  if (argn(2) < 2 | argn(2) > 3)
+    error("Wrong number of input arguments.");
+  elseif (argn(2) == 2)
+    rst = %T;
+  end
+  if (length (ndims (x)) > 2)
+    error ('The input should be two dimensional.');
+  end
+  if (length (ndims (lvl)) > 2)
+    error ('Only a maximum of two threshold levels accepted.');
+  end
+
+  [nT nc] = size (x);
+
+  global st0;
+  if (rst || isempty (st0))
+    st0 = zeros (1,nc);
+  end
+
+  if (length(lvl) == 1)
+    lvl = abs (lvl) .* [1 -1];
+  else
+    lvl = gsort(lvl, 'g', 'd');
+  end
+
+  v      = repmat(%nan, nT, nc);
+  v(1,:) = st0;
+
+  up    = x > lvl(1);
+  v(up) = 1;
+
+  dw    = x < lvl(2);
+  v(dw) = 0;
+
+  idx    = bool2s(isnan(v));
+  xhi = idx';
+  bool_discon = diff (xhi, 1, 2);
+  [Np Na]     = size (xhi);
+  ranges   = cell (1, Np);
+
+  for i = 1:Np
+    idxUp  = find (bool_discon(i,:) > 0) + 1;
+    idxDwn = find (bool_discon(i,:) < 0);
+    tLen   = length (idxUp) + length (idxDwn);
+
+    if (xhi(i,1) == 1)
+      ranges{i}(1) = 1;
+      ranges{i}(2:2:tLen+1) = idxDwn;
+      ranges{i}(3:2:tLen+1) = idxUp;
+    else
+      ranges{i}(1:2:tLen) = idxUp;
+      ranges{i}(2:2:tLen) = idxDwn;
+    end
+
+    if (xhi(i, $) == 1)
+      ranges{i}($+1) = Na;
+    end
+
+    tLen = length(ranges{i});
+    if (tLen ~= 0)
+      ranges{i} = matrix(ranges{i}, 2, tLen / 2);
+    end
+
+  end
+
+  if (Np == 1)
+    ranges = cell2mat(ranges);
+  end
+  if (nc == 1)
+    ranges = {ranges};
+  end
+
+  for i=1:nc
+    if (~isempty(ranges{i}))
+      prev         = ranges{i}(1,:)-1;
+      prev(prev<1) = 1;
+      st0          = v(prev, i);
+      ini_idx = ranges{i}(1,:);
+      end_idx = ranges{i}(2,:);
+      for j =1:length(ini_idx)
+        v(ini_idx(j):end_idx(j),i) = st0(j);
+      end
+    end
+  end
+
+  st0 = v($, :);
 
 endfunction
+
+//input validation:
+//assert_checkerror("schtrig(1)", "Wrong number of input arguments.");
+//assert_checkerror("schtrig(1, 2, 3, 4)", "Wrong number of input arguments.");
+
+//tests:
+//assert_checkequal(schtrig(ones(128, 1), -1), zeros(128, 1));
+//assert_checkequal(schtrig(ones(128, 1), -1), schtrig(ones(128, 1), -1, %F));
+//
+//assert_checkequal(schtrig([1 5 1], 3), schtrig([1 5 1], 3, %T));
+//assert_checkequal(schtrig([1 5 1], 3), [0 1 0]);
+//assert_checkequal(schtrig([1 5 1], 3, %F), schtrig([1 5 1], 3));
+//
+//assert_checkequal(schtrig([-3; 4; -1], -2), [0; 1; 1]);
+//assert_checkequal(schtrig([-3; 4; -1], -2, %F), schtrig([-3; 4; -1], -2));
+//
+//assert_checkequal(schtrig([1 -3; 2 4; 5 -1], -2), [0 0; 0 1; 1 1]);
+//assert_checkequal(schtrig([1 -3; 2 4; 5 -1], -2, %F), [1 0; 1 1; 1 1]);
+//
+//assert_checkequal(schtrig([1.1 1.5 0; 0.53 1.21 3.57; 5.34 -1.24 0], 0.424), [1 1 0;1 1 1;1 0 1]);
+//assert_checkequal(schtrig([1.1 1.5 0; 0.53 -1.21 3.57; 5.34 -1.24 0], 0.424, %F), [1 1 1;1 0 1;1 0 1]);