# HG changeset patch
# User Rik <rik@octave.org>
# Date 1391495532 28800
# Node ID 07ca8b9f8cab4ca5a29c52efaa9249613a943bd3
# Parent  cb377af34c00e65ac7a01fbe94399bdd72251d70
surface.m: Simplify input argument processing.

* surface.m (__surface__): Use cellfun call rather than loop to find first
string argument.  Use switch statement instead of long if/elseif tree.

diff -r cb377af34c00 -r 07ca8b9f8cab scripts/plot/draw/surface.m
--- a/scripts/plot/draw/surface.m	Sun Feb 02 22:21:45 2014 -0800
+++ b/scripts/plot/draw/surface.m	Mon Feb 03 22:32:12 2014 -0800
@@ -73,109 +73,110 @@
 
   h = 0;
   bad_usage = false;
-  firststring = nargin;
-  for i = 1 : (nargin - 1)
-    if (ischar (varargin{i}))
-      firststring = i;
-      break;
-    endif
-  endfor
+  firststring = find (cellfun ("isclass", varargin, "char"), 1);
+  if (isempty (firststring))
+    firststring = nargin;
+  endif
 
-  if (firststring > 5)
-    bad_usage = true;
-    return;
-  elseif (firststring == 5)
-    x = varargin{1};
-    y = varargin{2};
-    z = varargin{3};
-    c = varargin{4};
+  switch (firststring)
+    case 5
+      x = varargin{1};
+      y = varargin{2};
+      z = varargin{3};
+      c = varargin{4};
 
-    if (iscomplex (x) || iscomplex (y) || iscomplex (z) || iscomplex (c))
-      error ("mesh: X, Y, Z, C arguments must be real");
-    endif
+      if (iscomplex (x) || iscomplex (y) || iscomplex (z) || iscomplex (c))
+        error ("mesh: X, Y, Z, C arguments must be real");
+      endif
+
+      [z_nr, z_nc] = size (z);
+      [c_nr, c_nc, c_np] = size (c);
+      if (! (z_nr == c_nr && z_nc == c_nc && (c_np == 1 || c_np == 3)))
+        error ("surface: Z and C must have the same size");
+      endif
 
-    [z_nr, z_nc] = size (z);
-    [c_nr, c_nc, c_np] = size (c);
-    if (! (z_nr == c_nr && z_nc == c_nc && (c_np == 1 || c_np == 3)))
-      error ("surface: Z and C must have the same size");
-    endif
-
-    if (isvector (x) && isvector (y) && ismatrix (z))
-      if (rows (z) == length (y) && columns (z) == length (x))
-        x = x(:)';
-        y = y(:);
+      if (isvector (x) && isvector (y) && ismatrix (z))
+        if (rows (z) == length (y) && columns (z) == length (x))
+          x = x(:)';
+          y = y(:);
+        else
+          error ("surface: rows (Z) must be the same as length (Y) and columns (Z) must be the same as length (X)");
+        endif
+      elseif (ismatrix (x) && ismatrix (y) && ismatrix (z))
+        if (! size_equal (x, y, z))
+          error ("surface: X, Y, and Z must have the same dimensions");
+        endif
       else
-        error ("surface: rows (Z) must be the same as length (Y) and columns (Z) must be the same as length (X)");
+        error ("surface: X and Y must be vectors and Z must be a matrix");
       endif
-    elseif (ismatrix (x) && ismatrix (y) && ismatrix (z))
-      if (! size_equal (x, y, z))
-        error ("surface: X, Y, and Z must have the same dimensions");
+
+    case 4
+      x = varargin{1};
+      y = varargin{2};
+      z = varargin{3};
+      c = z;
+
+      if (iscomplex (x) || iscomplex (y) || iscomplex (z))
+        error ("mesh: X, Y, Z arguments must be real");
       endif
-    else
-      error ("surface: X and Y must be vectors and Z must be a matrix");
-    endif
-  elseif (firststring == 4)
-    x = varargin{1};
-    y = varargin{2};
-    z = varargin{3};
-    c = z;
-
-    if (iscomplex (x) || iscomplex (y) || iscomplex (z))
-      error ("mesh: X, Y, Z arguments must be real");
-    endif
 
-    if (isvector (x) && isvector (y) && ismatrix (z))
-      if (rows (z) == length (y) && columns (z) == length (x))
-        x = x(:)';
-        y = y(:);
+      if (isvector (x) && isvector (y) && ismatrix (z))
+        if (rows (z) == length (y) && columns (z) == length (x))
+          x = x(:)';
+          y = y(:);
+        else
+          error ("surface: rows (Z) must be the same as length (Y) and columns (Z) must be the same as length (X)");
+        endif
+      elseif (ismatrix (x) && ismatrix (y) && ismatrix (z))
+        if (! size_equal (x, y, z))
+          error ("surface: X, Y, and Z must have the same dimensions");
+        endif
       else
-        error ("surface: rows (Z) must be the same as length (Y) and columns (Z) must be the same as length (X)");
-      endif
-    elseif (ismatrix (x) && ismatrix (y) && ismatrix (z))
-      if (! size_equal (x, y, z))
-        error ("surface: X, Y, and Z must have the same dimensions");
+        error ("surface: X and Y must be vectors and Z must be a matrix");
       endif
-    else
-      error ("surface: X and Y must be vectors and Z must be a matrix");
-    endif
-  elseif (firststring == 3)
-    z = varargin{1};
-    c = varargin{2};
 
-    if (iscomplex (z) || iscomplex (c))
-      error ("mesh: X, C arguments must be real");
-    endif
+    case 3
+      z = varargin{1};
+      c = varargin{2};
+
+      if (iscomplex (z) || iscomplex (c))
+        error ("mesh: X, C arguments must be real");
+      endif
 
-    if (ismatrix (z) && !isvector (z) && !isscalar (z))
-      [nr, nc] = size (z);
-      x = 1:nc;
-      y = (1:nr)';
-    else
-      error ("surface: Z argument must be a matrix");
-    endif
-  elseif (firststring == 2)
-    z = varargin{1};
-    c = z;
+      if (ismatrix (z) && !isvector (z) && !isscalar (z))
+        [nr, nc] = size (z);
+        x = 1:nc;
+        y = (1:nr)';
+      else
+        error ("surface: Z argument must be a matrix");
+      endif
 
-    if (iscomplex (z))
-      error ("mesh: Z argument must be real");
-    endif
+    case 2
+      z = varargin{1};
+      c = z;
+
+      if (iscomplex (z))
+        error ("mesh: Z argument must be real");
+      endif
 
-    if (ismatrix (z) && !isvector (z) && !isscalar (z))
-      [nr, nc] = size (z);
-      x = 1:nc;
-      y = (1:nr)';
-    else
-      error ("surface: Z argument must be a matrix");
-    endif
-  elseif (firststring == 1)
-    x = 1:3;
-    y = x';
-    c = z = eye (3);
-  else
-    bad_usage = true;
-    return;
-  endif
+      if (ismatrix (z) && !isvector (z) && !isscalar (z))
+        [nr, nc] = size (z);
+        x = 1:nc;
+        y = (1:nr)';
+      else
+        error ("surface: Z argument must be a matrix");
+      endif
+
+    case 1
+      x = 1:3;
+      y = x';
+      c = z = eye (3);
+
+    otherwise
+      bad_usage = true;
+      return;
+  
+  endswitch
 
   if (firststring < nargin)
     other_args = varargin(firststring:end);