Implement autoreg_matrix.sci in Scilab

1 files changed, 31 insertions, 37 deletions

diff --git a/macros/autoreg_matrix.sci b/macros/autoreg_matrix.sci
index 2b70ced..95eb356 100644
--- a/macros/autoreg_matrix.sci
+++ b/macros/autoreg_matrix.sci
@@ -1,59 +1,53 @@
+function x = autoreg_matrix (y, k)
 // Given a time series (vector) Y, return a matrix with ones in the first column and the first K lagged values of Y in the other columns.
-
-//Calling Sequence
+//Calling Sequence:
 //autoreg_matrix(Y, K)
-
-//Parameters
-//Y: Vector
-//K: Scalar or Vector
-
-//Description
+//Parameters:
+//Y: vector
+//K: scalar
+//Description:
 // Given a time series (vector) Y, return a matrix with ones in the first column and the first K lagged values of Y in the other columns.
-//
 //In other words, for T > K, '[1, Y(T-1), ..., Y(T-K)]' is the t-th row of the result.
-//
 //The resulting matrix may be used as a regressor matrix in autoregressions.
-
-//Examples
-//autoreg_matrix([1,2,3],2)
+//Examples:
+//autoreg_matrix([1,2,3], 2)
 //ans =
 //      1.    0.    0.
 //      1.    1.    0.
 //      1.    2.    1.
 
-
-
-//function y = autoreg_matrix(Y, varargin)
-//funcprot(0);
-//rhs = argn(2)
-//if(rhs<2 | rhs>2)
-//error("Wrong number of input arguments.");
-//end
-//
-//	select(rhs)
-//	case 2 then
-//	y = callOctave("autoreg_matrix", Y, varargin(1));
-//	end
-//endfunction
-
-function X = autoreg_matrix (y, k)
-
   funcprot(0);
-  [nargout, nargin] = argn() ;
 
-  if (nargin ~= 2)
-    error('autoreg_matrix: invalid input') ;
+  if (argn(2) ~= 2)
+    error("autoreg_matrix: wrong number of input arguments") ;
   end
 
   if (~ (isvector (y)))
-    error ("autoreg_matrix: Y must be a vector");
+    error ("autoreg_matrix: y must be a vector");
   end
 
   T = length (y);
   y = matrix(y, T, 1);
-  X = ones (T, k+1);
-  for j = 1 : k;
-    X(:, j+1) = [(zeros (j, 1)); y(1:T-j)];
+  x = ones (T, k+1);
+  for j = 1 : k
+    x(:, j+1) = [(zeros(j, 1)); y(1:T-j)];
   end
 
 endfunction
+
+//input validation:
+//assert_checkerror("autoreg_matrix(1)", "autoreg_matrix: wrong number of input arguments");
+//assert_checkerror("autoreg_matrix(1, 2, 3)", "Wrong number of input arguments.");
+//assert_checkerror("autoreg_matrix(1, 2)", "autoreg_matrix: y must be a vector");
+//assert_checkerror("autoreg_matrix([1, 2; 3, 4], 2)", "autoreg_matrix: y must be a vector");
+
+//tests:
+//assert_checkequal(autoreg_matrix([1, 2], -1), []);
+//assert_checkequal(autoreg_matrix([1, 2, 3], 2), [1, 0, 0; 1, 1, 0; 1, 2, 1]);
+//assert_checkequal(autoreg_matrix([1, 2, 3], 2), autoreg_matrix([1; 2; 3], 2));
+//assert_checkequal(autoreg_matrix([1, 2, 3, 4, 5], 0), [1; 1; 1; 1; 1]);
+//assert_checkequal(autoreg_matrix([-1; -3; -5; -7; -9], 5), [1 0 0 0 0 0;1 -1 0 0 0 0;1 -3 -1 0 0 0;1 -5 -3 -1 0 0;1 -7 -5 -3 -1 0])
+//assert_checkequal(autoreg_matrix([1+2*%i, 5+4*%i, -4*%i, -1-6*%i], 1), [1, 0; 1, 1 + 2*%i; 1, 5 + 4*%i; 1, -4*%i]);
+//assert_checkequal(autoreg_matrix([1+2*%i, 5+4*%i, -4*%i, -1-6*%i], 3), autoreg_matrix([1+2*%i; 5+4*%i; -4*%i; -1-6*%i], 3));
+//assert_checkequal(autoreg_matrix([-%i; -3-%i; 5+6*%i; 7+9*%i;], 3), [1 0 0 0;1 -%i 0 0;1 -3-%i -%i 0;1 5+6*%i -3-%i -%i]);
+//assert_checkequal(autoreg_matrix([-%i; -3-%i; 5+6*%i; 7+9*%i;], 0), [1; 1; 1; 1]);