Add a useful package (from Source forge) for octave

[CreaPhase.git] / octave_packages / general-1.3.1 / @dict / subsasgn.m

diff --git a/octave_packages/general-1.3.1/@dict/subsasgn.m b/octave_packages/general-1.3.1/@dict/subsasgn.m
new file mode 100644 (file)
index 0000000..d2bce91
--- /dev/null
+++ b/octave_packages/general-1.3.1/@dict/subsasgn.m
@@ -0,0 +1,103 @@
+## Copyright (C) 2009 VZLU Prague, a.s., Czech Republic
+##
+## This program is free software; you can redistribute it and/or modify it under
+## the terms of the GNU General Public License as published by the Free Software
+## Foundation; either version 3 of the License, or (at your option) any later
+## version.
+##
+## This program is distributed in the hope that it will be useful, but WITHOUT
+## ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+## FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
+## details.
+##
+## You should have received a copy of the GNU General Public License along with
+## this program; if not, see <http://www.gnu.org/licenses/>.
+
+## -*- texinfo -*-
+## @deftypefn{Function File} {d =} subsasgn (d, s, val)
+## Overloaded subsasgn for dictionaries.
+## @end deftypefn
+
+## Author: Jaroslav Hajek <highegg@gmail.com>
+
+function d = subsasgn (d, s, val)
+  if (isempty (s))
+    error ("dict: missing index");
+  endif
+
+  switch (s(1).type)
+    case "()"
+      ind = s(1).subs;
+      if (numel (ind) == 1)
+        ind = ind{1};
+      else
+        error ("dict: needs exactly one index");
+      endif
+      if (ischar (ind))
+        ## Scalar assignment case. Search whether the key is present.
+        i = lookup (d.keys, ind, "m");
+        if (i)
+          ## The key is present; handle the rest of chain if needed,
+          ## then assign.
+          if (numel (s) > 1)
+            val = subsasgn (d.values{i}, s(2:end), val);
+          endif
+          d.values{i} = val;
+        else
+          ## The key is missing; handle the rest of chain if needed.
+          if (numel (s) > 1)
+            val = subsasgn ([], s(2:end), val);
+          endif
+          ## Look up the proper place to insert the new key.
+          i = lookup (d.keys, ind);
+          d.keys = [d.keys(1:i,1); {ind}; d.keys(i+1:end,1)];
+          ## Insert value.
+          d.values = [d.values(1:i,1); {val}; d.values(i+1:end,1)];
+        endif
+      elseif (iscellstr (ind))
+        ## Multiple assignment case. Perform checks.
+        if (numel (s) > 1)
+          error ("chained subscripts not allowed for multiple fields");
+        endif
+        if (isnull (val))
+          ## Deleting elements.
+          i = lookup (d.keys, ind, "m");
+          i = i(i != 0);
+          d.keys(i) = [];
+          d.values(i) = [];
+        elseif (iscell (val))
+          if (numel (val) == 1)
+            val = repmat (val, size (ind));
+          elseif (numel (ind) != numel (val))
+            error ("numbers of elements of index and rhs must match");
+          endif
+          ## Choose from two paths.
+          if (numel (ind) < numel (d.keys))
+            ## Scarce assignment. There's a good chance that all keys will be present.
+            i = lookup (d.keys, ind, "m");
+            mask = i != 0;
+            if (all (mask))
+              d.values(i) = val;
+            else
+              d.values(i(mask)) = val(mask);
+              mask = !mask;
+              [d.keys, i] = sort ([d.keys; ind(mask)(:)]);
+              d.values = [d.values; val(mask)(:)](i);
+            endif
+          else
+            ## Mass assignment. Probably most of the keys are new ones, so simply
+            ## melt all together.
+            [d.keys, i] = unique ([d.keys; ind(:)]);
+            d.values = [d.values; val(:)](i);
+          endif
+        else
+          error ("expected cell rhs for cell index");
+        endif
+      else
+        error ("invalid index");
+      endif
+    otherwise
+      error ("invalid subscript type for assignment");
+  endswitch
+endfunction
+