1 files changed, 50 insertions, 68 deletions
diff --git a/macros/prepad.sci b/macros/prepad.sci
index 4e517f8..d3595bf 100644
--- a/macros/prepad.sci
+++ b/macros/prepad.sci
@@ -1,83 +1,65 @@
 // Copyright (C) 2018 - IIT Bombay - FOSSEE
-//
 // This file must be used under the terms of the CeCILL.
 // This source file is licensed as described in the file COPYING, which
 // you should have received as part of this distribution.  The terms
 // are also available at
 // http://www.cecill.info/licences/Licence_CeCILL_V2-en.txt
-// Author:[insert name]
+// Author: Abinash Singh Under FOSSEE Internship
+// Modifieded by: Abinash Singh Under FOSSEE Internship
+// Last Modified on : 3 Feb 2024
 // Organization: FOSSEE, IIT Bombay
 // Email: toolbox@scilab.in
+/*
+Calling Sequence :
+    prepad (x, l)
+    prepad (x, l, c)
+    prepad (x, l, c, dim)
 
-
-function y = prepad (x, l, c, dim)
-// Calling sequence:
-// y= prepad (x, l)
-// y= prepad (x, l, c)
-// y= prepad (x, l, c, dim)
-// Prepend the scalar value c to the vector x until it is of length
-// l.  If c is not given, a value of 0 is used.
-//
-// If length (x) > l, elements from the beginning of x
-// are removed until a vector of length l is obtained.
-//
-// If x is a matrix, elements are prepended or removed from each row.
-//
-// If the optional argument dim is given, operate along this dimension.
-//
-// If dim is larger than the dimensions of x, the result will have
-// dim dimensions.
-
-//Test cases:
-//prepad ([1,2], 4,0,2)
-//Output: [0,0,1,2]
-
-
-[nargout,nargin]=argn();
-  if (nargin < 2 | nargin > 4)
-    error("wrong number of input arguments");
-  end
-
-  if (nargin < 3 | isempty (c))
-    c = 0;
-  else
-    if (~ isscalar (c))
-      error ("prepad: pad value C must be empty or a scalar");
+Prepend the scalar value c to the vector x until it is of length l. If c is not given, a value of 0 is used.
+If length (x) > l, elements from the beginning of x are removed until a vector of length l is obtained.
+If x is a matrix, elements are prepended or removed from each row.
+If the optional argument dim is given, operate along this dimension.
+If dim is larger than the dimensions of x, the result will have dim dimensions.
+*/
+function res = prepad(x,l,c,dim)
+    if nargin < 2 then 
+        error("Usage :  postpad(x,l,c(optional),dim(optional))")
     end
-  end
-//dim=1;
-  nd = ndims (x);
-  sz = size (x);
-  if (argn(2) < 4)
-    // Find the first non-singleton dimension.
-    dim = find (sz > 1, 1)
-    if (dim == [])
-      dim = 1
+    if nargin < 3 then 
+        c = 0 ;
     end
-  else
-    if (~(isscalar (dim) & dim == fix (dim) & dim >= 1))
-      error ("prepad: DIM must be an integer and a valid dimension");
+    if nargin < 4 then 
+        dim = find(size(x)>1)
+        if isempty(dim) then dim = 2 end
+        if isvector(dim) then dim = dim(1) end
     end
-  end
-
-  if (~ isscalar (l) | l < 0)
-    error ("prepad: length L must be a positive scalar");
-  end
 
-  if (dim > nd)
-    sz(nd+1:dim) = 1;
-  end
-
-  d = sz(dim);
+    if l < size(x,dim) then
+        if isvector(x) then 
+            start = length(x) - l+1;
+            res=x(start:$)
+            return;
+        else
+            error("prepad : l must be greter than dim size for matrices")
+        end
+        
+    end
+    
+    if dim == 1 then 
+        res = [ c* ones( l - size(x,1) , size(x,2)) ; x]
+    elseif dim == 2 then 
+        res = [ c* ones( size(x,1) , l - size(x,2)) x]
+    else
+        error("prepad : Invalid value for arg dim 1 or 2 expected")
+    end
+endfunction
 
-  if (d >= l)
-//    idx = repmat ({':'}, nd, 1);
-//    idx(dim) = (d-l+1) : d;
-//    y = x(idx(:));
-      y=x;
-  else
-    sz(dim) = l - d;
-    y = cat (dim, c(ones (sz(1),sz(2))), x);
-  end
+/*
+#test for row vectors
+prepad([1 2 3 4],6) 
+prepad([1 ;2 ;3 ;4],6) 
+prepad([1 2 3 4;5 6 7 8;9 10 11 12],6) 
+prepad([1 2 ;3 4;5 6],6,-1) 
 
-endfunction
+// FIXME : Tests for 2d and high dimesnsional matrices
+*/