Added special-case logical-indexing function * logical-index.h (New file) : Logical-indexing function. May be called on octave_value types via call_bool_index * nz-iterators.h : Add base-class nz_iterator for iterator types. Array has template bool for whether to internally store row-col or compute on the fly Add skip_ahead method which skips forward to the next nonzero after its argument Add flat_index for computing octave_idx_type index of current position (with assertion failure in the case of overflow) Move is_zero to separate file * ov-base-diag.cc, ov-base-mat.cc, ov-base-sparse.cc, ov-perm.cc (do_index_op): Add call to call_bool_index in logical-index.h * Array.h : Move forward-declaration for array_iterator to separate header file * dim-vector.cc (dim_max): Refers to idx-bounds.h (max_idx) * array-iter-decl.h (New file): Header file for forward declaration of array-iterator * direction.h : Add constants fdirc and bdirc to avoid having to reconstruct them * dv-utils.h, dv-utils.cc (New files) : Utility functions for querying and constructing dim-vectors * idx-bounds.h (New file) : Utility constants and functions for determining whether things will overflow the maximum allowed bounds * interp-idx.h (New function : to_flat_idx) : Converts row-col pair to linear index of octave_idx_type * is-zero.h (New file) : Function for determining whether an element is zero * logical-index.tst : Add tests for correct return-value dimensions and large sparse matrix behavior

--- a/libinterp/octave-value/ov-base-diag.cc	Mon Jul 14 13:07:59 2014 -0600
+++ b/libinterp/octave-value/ov-base-diag.cc	Fri Jul 25 13:39:31 2014 -0600
@@ -37,6 +37,7 @@
 #include "gripes.h"
 #include "oct-stream.h"
 #include "ops.h"
+#include "logical-index.h"
 
 #include "ls-oct-ascii.h"
 
@@ -125,6 +126,8 @@
             retval = to_dense ().do_index_op (idx, resize_ok);
         }
     }
+  else if (idx.length () == 1 && idx(0).is_bool_type ())
+    retval = call_bool_index (matrix, idx(0));
   else
     retval = to_dense ().do_index_op (idx, resize_ok);