Mercurial > hg > octave-lyh

changeset 13481:e643b9393eba

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Merge with Savannah
author Jordi Gutiérrez Hermoso <jordigh@gmail.com>
date Sat, 23 Apr 2011 20:14:08 -0500
parents f154bef3cf61 (diff) daa94255fff1 (current diff)
children 0daa1ac62b00
files
diffstat 7 files changed, 304 insertions(+), 178 deletions(-) [+]
line wrap: on
line diff
--- a/doc/faq/OctaveFAQ.texi
+++ b/doc/faq/OctaveFAQ.texi
@@ -780,15 +780,15 @@
 @end itemize
 @end itemize
 
-@node How do I ...?
-@chapter  How do I ...?
+@node Using Octave
+@chapter  Using Octave
 
 @menu
 * How do I set the number of displayed decimals?::
 @end menu
 
 @cindex Tips and tricks
-@cindex How do I @dots{} ?
+@cindex Using Octave
 
 @node How do I set the number of displayed decimals?
 @section How do I set the number of displayed decimals?
@@ -804,6 +804,19 @@
 @end group
 @end example
 
+@menu
+* How does Octave solve linear systems?
+@end menu
+
+@cindex backslash operator
+
+In addition to consulting Octave's source for the precise details, the
+Octave manual contains a complete high-level description of the
+algorithm that Octave uses to decide how to solve a particular linear
+system, e.g. how the backslash operator @code{A\x} will be interpreted.
+Sections ``Techniques used for Linear Algebra'' and ``Linear Algebra on
+Sparse Matrices'' from the manual describe this procedure.
+
 @node @sc{Matlab} compatibility
 @chapter Porting programs from @sc{Matlab} to Octave
 
--- a/doc/interpreter/expr.txi
+++ b/doc/interpreter/expr.txi
@@ -1239,51 +1239,62 @@
 any such mistake.
 
 When operators of equal precedence are used together, the leftmost
-operator groups first, except for the assignment and exponentiation
-operators, which group in the opposite order.  Thus, the expression
-@code{a - b + c} groups as @code{(a - b) + c}, but the expression
-@code{a = b = c} groups as @code{a = (b = c)}.
+operator groups first, except for the assignment operators, which group
+in the opposite order.  Thus, the expression @code{a - b + c} groups as
+@code{(a - b) + c}, but the expression @code{a = b = c} groups as
+@code{a = (b = c)}.
 
 The precedence of prefix unary operators is important when another
 operator follows the operand.  For example, @code{-x^2} means
 @code{-(x^2)}, because @samp{-} has lower precedence than @samp{^}.
 
-Here is a table of the operators in Octave, in order of increasing
-precedence.
+Here is a table of the operators in Octave, in order of decreasing
+precedence.  Unless noted, all operators group left to right.
 
 @table @code
-@item statement separators
-@samp{;}, @samp{,}.
+@item function call and array indexing, cell array indexing, and structure element indexing
+@samp{()}  @samp{@{@}} @samp{.}
+
+@item postfix increment, and postfix decrement
+@samp{++}  @samp{--}
+
+These operators group right to left.
+
+@item transpose and exponentiation
+@samp{'} @samp{.'} @samp{^} @samp{**} @samp{.^} @samp{.**}
 
-@item assignment
-@samp{=}, @samp{+=}, @samp{-=}, @samp{*=},@samp{/=}.  This operator
-groups right to left.
+@item unary plus, unary minus, prefix increment, prefix decrement, and logical "not"
+@samp{+} @samp{-} @samp{++}  @samp{--} @samp{~} @samp{!}
+
+@item multiply and divide
+@samp{*} @samp{/} @samp{\} @samp{.\} @samp{.*} @samp{./}
 
-@item logical "or" and "and"
-@samp{||}, @samp{&&}.
+@item add, subtract
+@samp{+} @samp{-}
 
-@item element-wise "or" and "and"
-@samp{|}, @samp{&}.
+@item colon
+@samp{:}
 
 @item relational
-@samp{<}, @samp{<=}, @samp{==}, @samp{>=}, @samp{>}, @samp{!=},
-@samp{~=}.
+@samp{<} @samp{<=} @samp{==} @samp{>=} @samp{>} @samp{!=}
+@samp{~=}
 
-@item colon
-@samp{:}.
+@item element-wise "and"
+@samp{&}
 
-@item add, subtract
-@samp{+}, @samp{-}.
+@item element-wise "or"
+@samp{|}
 
-@item multiply, divide
-@samp{*}, @samp{/}, @samp{\}, @samp{.\}, @samp{.*}, @samp{./}.
+@item logical "and"
+@samp{&&}
 
-@item transpose
-@samp{'}, @samp{.'}
+@item logical "or"
+@samp{||}
 
-@item unary plus, minus, increment, decrement, and ``not''
-@samp{+}, @samp{-}, @samp{++}, @samp{--}, @samp{!}, @samp{~}.
+@item assignment
+@samp{=} @samp{+=} @samp{-=} @samp{*=} @samp{/=} @samp{\=}
+@samp{^=} @samp{.*=} @samp{./=} @samp{.\=} @samp{.^=} @samp{|=}
+@samp{&=}
 
-@item exponentiation
-@samp{^}, @samp{**}, @samp{.^}, @samp{.**}.
+These operators group right to left.
 @end table
--- a/scripts/specfun/nthroot.m
+++ b/scripts/specfun/nthroot.m
@@ -35,8 +35,9 @@
 ## @end group
 ## @end example
 ##
-## @var{n} must be a scalar.  If @var{n} is not an even integer and @var{X} has
-## negative entries, an error is produced.
+## @var{x} must have all real entries.  @var{n} must be a scalar. 
+## If @var{n} is an even integer and @var{X} has negative entries, an
+## error is produced.
 ## @seealso{realsqrt, sqrt, cbrt}
 ## @end deftypefn
 
@@ -46,7 +47,11 @@
     print_usage ();
   endif
 
-  if (! isscalar (n))
+  if (any (iscomplex (x(:))))
+    error ("nthroot: X must not contain complex values");
+  endif
+
+  if (! isscalar (n) || n == 0)
     error ("nthroot: N must be a nonzero scalar");
   endif
 
@@ -58,7 +63,7 @@
     y = 1 ./ nthroot (x, -n);
   else
     ## Compute using power.
-    if (n == round (n) && mod (n, 2) == 1)
+    if (n == fix (n) && mod (n, 2) == 1)
       y = abs (x) .^ (1/n) .* sign (x);
     elseif (any (x(:) < 0))
       error ("nthroot: if X contains negative values, N must be an odd integer");
@@ -66,7 +71,7 @@
       y = x .^ (1/n);
     endif
 
-    if (finite (n) && n > 0 && n == round (n))
+    if (finite (n) && n > 0 && n == fix (n))
       ## Correction.
       y = ((n-1)*y + x ./ (y.^(n-1))) / n;
       y = merge (finite (y), y, x);
@@ -76,8 +81,18 @@
 
 endfunction
 
-%!assert(nthroot(-32,5), -2);
-%!assert(nthroot(81,4), 3);
-%!assert(nthroot(Inf,4), Inf);
-%!assert(nthroot(-Inf,7), -Inf);
-%!assert(nthroot(-Inf,-7), 0);
+%!assert (nthroot(-32,5), -2);
+%!assert (nthroot(81,4), 3);
+%!assert (nthroot(Inf,4), Inf);
+%!assert (nthroot(-Inf,7), -Inf);
+%!assert (nthroot(-Inf,-7), 0);
+
+%% Test input validation
+%!error (nthroot ())
+%!error (nthroot (1))
+%!error (nthroot (1,2,3))
+%!error (nthroot (1+j,2))
+%!error (nthroot (1,[1 2]))
+%!error (nthroot (1,0))
+%!error (nthroot (-1,2))
+
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -736,7 +736,7 @@
 
 ## We require Bison.
 #parse.cc : parse.y
-#	@echo "expect 14 shift/reduce conflicts"
+#	@echo "expect 16 shift/reduce conflicts"
 #	$(YACC) $(YFLAGS) --output=$@ --defines=y.tab.h $<
 
 #lex.cc : lex.l
--- a/src/lex.ll
+++ b/src/lex.ll
@@ -164,13 +164,13 @@
     } \
   while (0)
 
-#define BIN_OP_RETURN(tok, convert, bos) \
+#define BIN_OP_RETURN_INTERNAL(tok, convert, bos, qit) \
   do \
     { \
       yylval.tok_val = new token (input_line_number, current_input_column); \
       token_stack.push (yylval.tok_val); \
       current_input_column += yyleng; \
-      lexer_flags.quote_is_transpose = false; \
+      lexer_flags.quote_is_transpose = qit; \
       lexer_flags.convert_spaces_to_comma = convert; \
       lexer_flags.looking_for_object_index = false; \
       lexer_flags.at_beginning_of_statement = bos; \
@@ -178,6 +178,21 @@
     } \
   while (0)
 
+#define XBIN_OP_RETURN_INTERNAL(tok, convert, bos, qit) \
+  do \
+    { \
+      gripe_matlab_incompatible_operator (yytext); \
+      BIN_OP_RETURN_INTERNAL (tok, convert, bos, qit); \
+    } \
+  while (0)
+
+#define BIN_OP_RETURN(tok, convert, bos) \
+  do \
+    { \
+      BIN_OP_RETURN_INTERNAL (tok, convert, bos, false); \
+    } \
+  while (0)
+
 #define XBIN_OP_RETURN(tok, convert, bos) \
   do \
     { \
@@ -896,8 +911,8 @@
 ".^"    { LEXER_DEBUG (".^"); BIN_OP_RETURN (EPOW, false, false); }
 ".**"   { LEXER_DEBUG (".**"); XBIN_OP_RETURN (EPOW, false, false); }
 ".'"    { LEXER_DEBUG (".'"); do_comma_insert_check (); BIN_OP_RETURN (TRANSPOSE, true, false); }
-"++"    { LEXER_DEBUG ("++"); do_comma_insert_check (); XBIN_OP_RETURN (PLUS_PLUS, true, false); }
-"--"    { LEXER_DEBUG ("--"); do_comma_insert_check (); XBIN_OP_RETURN (MINUS_MINUS, true, false); }
+"++"    { LEXER_DEBUG ("++"); do_comma_insert_check (); XBIN_OP_RETURN_INTERNAL (PLUS_PLUS, true, false, true); }
+"--"    { LEXER_DEBUG ("--"); do_comma_insert_check (); XBIN_OP_RETURN_INTERNAL (MINUS_MINUS, true, false, true); }
 "<="    { LEXER_DEBUG ("<="); BIN_OP_RETURN (EXPR_LE, false, false); }
 "=="    { LEXER_DEBUG ("=="); BIN_OP_RETURN (EXPR_EQ, false, false); }
 "~="    { LEXER_DEBUG ("~="); BIN_OP_RETURN (EXPR_NE, false, false); }
--- a/src/oct-parse.yy
+++ b/src/oct-parse.yy
@@ -471,7 +471,7 @@
 %type <tree_matrix_type> matrix_rows matrix_rows1
 %type <tree_cell_type> cell_rows cell_rows1
 %type <tree_expression_type> matrix cell
-%type <tree_expression_type> primary_expr postfix_expr prefix_expr binary_expr
+%type <tree_expression_type> primary_expr oper_expr
 %type <tree_expression_type> simple_expr colon_expr assign_expr expression
 %type <tree_identifier_type> identifier fcn_name magic_tilde
 %type <tree_identifier_type> superclass_identifier meta_identifier
@@ -514,7 +514,6 @@
 %type <dummy_type> class_body
 
 // Precedence and associativity.
-%left ';' ',' '\n'
 %right '=' ADD_EQ SUB_EQ MUL_EQ DIV_EQ LEFTDIV_EQ POW_EQ EMUL_EQ EDIV_EQ ELEFTDIV_EQ EPOW_EQ OR_EQ AND_EQ LSHIFT_EQ RSHIFT_EQ
 %left EXPR_OR_OR
 %left EXPR_AND_AND
@@ -525,8 +524,9 @@
 %left ':'
 %left '-' '+' EPLUS EMINUS
 %left '*' '/' LEFTDIV EMUL EDIV ELEFTDIV
-%left UNARY PLUS_PLUS MINUS_MINUS EXPR_NOT
+%right UNARY EXPR_NOT
 %left POW EPOW QUOTE TRANSPOSE
+%right PLUS_PLUS MINUS_MINUS
 %left '(' '.' '{'
 
 // Where to start.
@@ -796,69 +796,61 @@
                   { lexer_flags.looking_at_indirect_ref = true; }
                 ;
 
-postfix_expr    : primary_expr
+oper_expr       : primary_expr
                   { $$ = $1; }
-                | postfix_expr '(' ')'
+                | oper_expr PLUS_PLUS
+                  { $$ = make_postfix_op (PLUS_PLUS, $1, $2); }
+                | oper_expr MINUS_MINUS
+                  { $$ = make_postfix_op (MINUS_MINUS, $1, $2); }
+                | oper_expr '(' ')'
                   { $$ = make_index_expression ($1, 0, '('); }
-                | postfix_expr '(' arg_list ')'
+                | oper_expr '(' arg_list ')'
                   { $$ = make_index_expression ($1, $3, '('); }
-                | postfix_expr '{' '}'
+                | oper_expr '{' '}'
                   { $$ = make_index_expression ($1, 0, '{'); }
-                | postfix_expr '{' arg_list '}'
+                | oper_expr '{' arg_list '}'
                   { $$ = make_index_expression ($1, $3, '{'); }
-                | postfix_expr PLUS_PLUS
-                  { $$ = make_postfix_op (PLUS_PLUS, $1, $2); }
-                | postfix_expr MINUS_MINUS
-                  { $$ = make_postfix_op (MINUS_MINUS, $1, $2); }
-                | postfix_expr QUOTE
+                | oper_expr QUOTE
                   { $$ = make_postfix_op (QUOTE, $1, $2); }
-                | postfix_expr TRANSPOSE
+                | oper_expr TRANSPOSE
                   { $$ = make_postfix_op (TRANSPOSE, $1, $2); }
-                | postfix_expr indirect_ref_op STRUCT_ELT
+                | oper_expr indirect_ref_op STRUCT_ELT
                   { $$ = make_indirect_ref ($1, $3->text ()); }
-                | postfix_expr indirect_ref_op '(' expression ')'
+                | oper_expr indirect_ref_op '(' expression ')'
                   { $$ = make_indirect_ref ($1, $4); }
-                ;
-
-prefix_expr     : postfix_expr
-                  { $$ = $1; }
-                | binary_expr
-                  { $$ = $1; }
-                | PLUS_PLUS prefix_expr %prec UNARY
+                | PLUS_PLUS oper_expr %prec UNARY
                   { $$ = make_prefix_op (PLUS_PLUS, $2, $1); }
-                | MINUS_MINUS prefix_expr %prec UNARY
+                | MINUS_MINUS oper_expr %prec UNARY
                   { $$ = make_prefix_op (MINUS_MINUS, $2, $1); }
-                | EXPR_NOT prefix_expr %prec UNARY
+                | EXPR_NOT oper_expr %prec UNARY
                   { $$ = make_prefix_op (EXPR_NOT, $2, $1); }
-                | '+' prefix_expr %prec UNARY
+                | '+' oper_expr %prec UNARY
                   { $$ = make_prefix_op ('+', $2, $1); }
-                | '-' prefix_expr %prec UNARY
+                | '-' oper_expr %prec UNARY
                   { $$ = make_prefix_op ('-', $2, $1); }
-                ;
-
-binary_expr     : prefix_expr POW prefix_expr
+                | oper_expr POW oper_expr
                   { $$ = make_binary_op (POW, $1, $2, $3); }
-                | prefix_expr EPOW prefix_expr
+                | oper_expr EPOW oper_expr
                   { $$ = make_binary_op (EPOW, $1, $2, $3); }
-                | prefix_expr '+' prefix_expr
+                | oper_expr '+' oper_expr
                   { $$ = make_binary_op ('+', $1, $2, $3); }
-                | prefix_expr '-' prefix_expr
+                | oper_expr '-' oper_expr
                   { $$ = make_binary_op ('-', $1, $2, $3); }
-                | prefix_expr '*' prefix_expr
+                | oper_expr '*' oper_expr
                   { $$ = make_binary_op ('*', $1, $2, $3); }
-                | prefix_expr '/' prefix_expr
+                | oper_expr '/' oper_expr
                   { $$ = make_binary_op ('/', $1, $2, $3); }
-                | prefix_expr EPLUS prefix_expr
+                | oper_expr EPLUS oper_expr
                   { $$ = make_binary_op ('+', $1, $2, $3); }
-                | prefix_expr EMINUS prefix_expr
+                | oper_expr EMINUS oper_expr
                   { $$ = make_binary_op ('-', $1, $2, $3); }
-                | prefix_expr EMUL prefix_expr
+                | oper_expr EMUL oper_expr
                   { $$ = make_binary_op (EMUL, $1, $2, $3); }
-                | prefix_expr EDIV prefix_expr
+                | oper_expr EDIV oper_expr
                   { $$ = make_binary_op (EDIV, $1, $2, $3); }
-                | prefix_expr LEFTDIV prefix_expr
+                | oper_expr LEFTDIV oper_expr
                   { $$ = make_binary_op (LEFTDIV, $1, $2, $3); }
-                | prefix_expr ELEFTDIV prefix_expr
+                | oper_expr ELEFTDIV oper_expr
                   { $$ = make_binary_op (ELEFTDIV, $1, $2, $3); }
                 ;
 
@@ -866,9 +858,9 @@
                   { $$ = finish_colon_expression ($1); }
                 ;
 
-colon_expr1     : prefix_expr
+colon_expr1     : oper_expr
                   { $$ = new tree_colon_expression ($1); }
-                | colon_expr1 ':' prefix_expr
+                | colon_expr1 ':' oper_expr
                   {
                     if (! ($$ = $1->append ($3)))
                       ABORT_PARSE;
--- a/test/test_parser.m
+++ b/test/test_parser.m
@@ -28,142 +28,222 @@
 %!assert ({1 2,{3,4}}, {1,2,{3,4}})
 %!assert ({1,2,{3 4}}, {1,2,{3,4}})
 
-%# Tests for operator precedence as documented in section 8.8 of manual
-%# There are 11 levels of precedence from "exponentiation" (highest) down to
-%# "statement operators" (lowest).
-%#
-%# Level 11 (exponentiation) overrides all others
+## Tests for operator precedence as documented in section 8.8 of manual
+## There are 13 levels of precedence from "parentheses and indexing" (highest)
+## down to "statement operators" (lowest).
+##
+## Level 13 (parentheses and indexing)
+## Overrides all other levels
+%!test
+%!  a.b = 1;
+%!  assert (a. b++, 1)
+%!  assert (a.b, 2)
+%!  clear a;
+%!  a.b = [0 1];
+%!  b = 2;
+%!  assert (a.b', [0;1])
+%!  assert (!a .b, logical ([1 0]))
+%!  assert (3*a .b, [0 3])
+%!  assert (a. b-1, [-1 0])
+%!  assert (a. b:3, 0:3)
+%!  assert (a. b>0.5, logical ([0 1]))
+%!  assert (a. b&0, logical ([0 0]))
+%!  assert (a. b|0, logical ([0 1]))
+%!  a.b = [1 2];
+%!  assert (a. b&&0, false)
+%!  assert (a. b||0, true)
+%!  a.b += a. b*2;
+%!  assert (a.b, [3 6])
+## Level 12 (postfix increment and decrement)
 %!test
-%!  assert (-2^2, -4)
-%!  assert (!0^0, false);
-# FIXME: This test is failing.  Transpose mistakenly has higher priority.
-%!  assert ([2 3].^2', [4; 9])
-%!  assert (2*3^2, 18)
-%!  assert (2+3^2, 11)
-%!  assert ([1:10](1:2^2), [1 2 3 4])
-%!  assert (3 > 2^2, false)
-%!  assert (1 & 0^0, true)
-%!  assert (1 && 0^0, true)
+%!  a = [3 5];
+%!  assert (2.^a ++, [8 32])
+%!  assert (a, [4 6])
+%!  assert (a--', [4; 6])
+%!  assert (a, [3 5])
+%!  a = 0;
+%!  assert (!a --, true)
+%!  assert (-a ++, 1)
+%!  assert (3*a ++, 0)
+%!  assert (a++-2, -1)
+%!  assert (1:a ++, 1:2)
+%!  assert (4>a++, true)
+%!  a = [0 -1];
+%!  assert ([1 1] & a++, logical ([0 1]))
+%!  assert ([0 0] | a++, logical ([1 0]))
+%!  a = 0;
+%!  assert (1 && a ++, false)
+%!  assert (0 || a --, true)
+%!  a = 5; b = 2;
+%!  b +=a ++;
+%!  assert (b, 7)
+
+## Level 11 (transpose and exponentiation)
+%!test
+%!  assert (-2 ^2, -4)
+%!  assert (!0 ^0, false)
+%!  assert (2*3 ^2, 18)
+%!  assert (2+3 ^2, 11)
+%!  assert ([1:10](1:2 ^2), [1 2 3 4])
+%!  assert (3>2 ^2, false)
+%!  assert (1&0 ^0, true)
+%!  assert (0|0 ^0, true)
+%!  assert (1&&0 ^0, true)
+%!  assert (0||0 ^0, true)
 %!  a = 3;
-%!  a *= 0^0;
+%!  a *= 0 ^0;
 %!  assert (a, 3)
-%# Level 10 (unary plus, increment, not)
+## Level 10 (unary plus/minus, prefix increment/decrement, not)
 %!test
-# FIXME: No test for increment and transpose that I can think of.
 %!  a = 2;
-%!  assert (++a*3, 9)
-%!  assert (a++-2, 1)
-%!  assert (a, 4)
-%!  assert ([1:10](1:++a), [1:5])
-%!  assert (5 == a++, true)
-%!  assert (7 == ++a, true)
+%!  assert (++ a*3, 9)
+%!  assert (-- a-2, 0)
+%!  assert (a, 2)
+%!  assert (! a-2, -2)
+%!  assert ([1:10](++ a:5), 3:5)
+%!  a = [1 0];
+%!  assert (! a>=[1 0], [false true])
 %!  a = 0;
-%!  assert (1 & a++, false)
-%!  assert (a, 1)
-%!  assert (1 && --a, false)
+%!  assert (++ a&1, true)
+%!  assert (-- a|0, false)
+%!  assert (-- a&&1, true)
+%!  assert (++ a||0, false)
 %!  a = 3;
-%!  a *= a++;
-%!  assert (a, 12)
-%# Level 9 (transpose)
+%!  a *= ++a;
+%!  assert (a, 16)
+## Level 9 (multiply, divide)
 %!test
-%!  assert ([1 2]*[3 4]', 11)
-%!  assert ([1 2]'+[3 4]', [4; 6])
-%!  assert (1:5', 1:5)
-%!  assert ([1; 2] == [1 2]', [true; true])
-%!  assert ([1; 0] & [1 0]', [true; false])
-# FIXME: No test for transpose and short-circuit operator that I can think of.
-%!  a = [1 2];
-%!  a *= [3 4]';
-%!  assert (a, 11)
-%# Level 8 (multiply, divide)
-%!test
-%!  assert (3 + 4 * 5, 23)
-%!  assert (3 + 4 * 5, 23)
-%!  assert (5*1:6, [5 6])
-%!  assert (3 > 1 * 5, false)
-%!  assert (1 & 1 * 0, false)
-%!  assert (1 && 1 * 0, false)
+%!  assert (3+4 * 5, 23)
+%!  assert (5 * 1:6, [5 6])
+%!  assert (3>1 * 5, false)
+%!  assert (1&1 * 0, false)
+%!  assert (1|1 * 0, true)
+%!  assert (1&&1 * 0, false)
+%!  assert (1||1 * 0, true)
 %!  a = 3;
 %!  a /= a * 2;
 %!  assert (a, 0.5)
-%# Level 7 (add, subtract)
+## Level 8 (add, subtract)
 %!test
 %!  assert ([2 + 1:6], 3:6)
-%!  assert (3 > 1 + 5, false)
-%!  assert (1 & 1 - 1, false)
-%!  assert (1 && 1 - 1, false)
+%!  assert (3>1 + 5, false)
+%!  assert (1&1 - 1, false)
+%!  assert (0|1 - 2, true)
+%!  assert (1&&1 - 1, false)
+%!  assert (0||1 - 2, true)
 %!  a = 3;
 %!  a *= 1 + 1;
 %!  assert (a, 6)
-%# Level 6 (colon)
+## Level 7 (colon)
 %!test
-%!  assert (5:-1: 3 > 4, [true false false])
-%!  assert (1: 3 & 1, [true true true])
-%!  assert (-1: 3 && 1, false)
+%!  assert (5:-1: 3>4, [true false false])
+%!  assert (1: 3&1, [true true true])
+%!  assert (1: 3|0, [true true true])
+%!  assert (-1: 3&&1, false)
+%!  assert (-1: 3||0, false)
 %!  a = [1:3];
 %!  a += 3 : 5;
 %!  assert (a, [4 6 8])
-%# Level 5 (relational)
+## Level 6 (relational)
 %!test
-%!  assert (0 == -1 & 0, false)
-%!  assert (0 == -1 && 0, false)
+%!  assert (0 == -1&0, false)
+%!  assert (1 == -1|0, false)
+%!  assert (0 == -1&&0, false)
+%!  assert (1 == -1||0, false)
 %!  a = 2;
 %!  a *= 3 > 1;
 %!  assert (a, 2)
-%# Level 4 (element-wise and, or)
+## Level 5 (element-wise and)
 %!test
-%!  assert (0 & 1 || 1, true)
-%!  assert (0 == -1 && 0, false)
+%!  assert (0 & 1|1, true)
+%!  assert ([0 1] & 1&&1, false)
+%!  assert (0 & 1||1, true)
 %!  a = 2;
 %!  a *= 3 & 1;
 %!  assert (a, 2)
-%# Level 3 (logical and, or)
+## Level 4 (element-wise or)
 %!test
+%!  assert ([0 1] | 1&&0, false)
+%!  assert ([0 1] | 1||0, true)
+%!  a = 2;
+%!  a *= 0 | 1;
+%!  assert (a, 2)
+## Level 3 (logical and)
+%!test
+%!  assert (0 && 1||1, true)
 %!  a = 2;
 %!  a *= 3 && 1;
 %!  assert (a, 2)
+## Level 2 (logical or)
+%!test
+%!  a = 2;
+%!  a *= 0 || 1;
+%!  assert (a, 2)
 
-%# Tests for operator precedence within each level where ordering should
-%# be left to right except for exponents and assignments.
-%# Level 11 (exponentiation)
+## Tests for operator precedence within each level where ordering should
+## be left to right except for postfix and assignment operators.
+
+## Level 13 (parentheses and indexing)
 %!test
-%# FIXME : Exponentiation seems to work left to right, despite the 
-%#         documentation and ordinary mathematical rules of precedence.
-%!  assert (2^3**2, 512)
-%# Level 10 (unary plus, increment, not)
+%!  a.b1 = 2;
+%!  assert (a.(strcat('b','1'))++, 2)
+%!  assert (a.b1, 3)
+%!  b = {1 2 3 4 5};
+%!  assert (b{(a. b1 + 1)}, 4)
+%!  b = 1:5;
+%!  assert (b(a. b1 + 1), 4)
+%!  assert ([2 3].^2', [4; 9])
+## Level 12 (postfix increment and decrement)
+## No tests possible since a++-- is not valid
+## Level 11 (transpose and exponentiation)
+## Note: Exponentiation works left to right for compatibility with Matlab.
+%!  assert (2^3**2, 64)
+%!  assert ([2 3].^2.', [4;9])
+%!  assert ([2 3].'.^2, [4;9])
+%!  assert (3*4i'.', 0 - 12i)
+%!  assert (3*4i.'.', 0 + 12i)
+## Level 10 (unary plus/minus, prefix increment/decrement, not)
 %!test
 %!  assert (+-+1, -1)
-%!  a = 0;
-%# FIXME : Should we test for this corner case at all?
-%#         (unary minus)(auto-decrement operator)
-%!  assert (---a, 1);
 %!  a = -1;
 %!  assert (!++a, true)
 %!  assert (a, 0)
 %!  assert (-~a, -1)
-%!  assert (!~a++, false)
-%!  assert (a, 1)
-%# Level 9 (transpose)
+%!  assert (!~--a, true)
+%!  assert (a, -1)
+## Level 9 (multiply, divide)
 %!test
-%!  assert (3*4i'.', 0 - 12i)
-%!  assert (3*4i.'.', 0 + 12i)
-%# Level 8 (multiply, divide)
+%!  assert (3 * 4 / 5, 2.4)
+%!  assert (3 ./ 4 .* 5, 3.75)
+%!  assert (2 * 4 \ 6, 0.75)
+%!  assert (2 .\ 4 .* 6, 12)
+## Level 8 (add, subtract)
 %!test
-%!assert (3 * 4 / 5, 2.4)
-%!assert (3 ./ 4 .* 5, 3.75)
-%# Level 7 (add, subtract)
-%!test
-%!assert (-3 - 4 + 1 + 3 * 2, 0)
-%# Level 5 (relational)
+%!  assert (-3 - 4 + 1 + 3 * 2, 0)
+## Level 7 (colon)
+## No tests possible because colon operator can't be combined with second colon operator
+## Level 6 (relational)
 %!test
 %!  assert (0 < 1 <= 0.5 == 0 >= 0.5 > 0, true)
 %!  assert (1 < 1 == 0 != 0, true)
 %!  assert (1 < 1 == 0 ~= 0, true)
-%# Level 4 (element-wise and, or)
+## Level 5 (element-wise and)
+## No tests possible.  Only one operator (&) at this precedence level and operation is associative.
+## Level 4 (element-wise or)
+## No tests possible.  Only one operator (|) at this precedence level and operation is associative.
+## Level 3 (logical and)
 %!test
-%!  assert ([ 1 0] & [0 1] | [1 0], [true false])
-%# Level 2 (assignment)
+%!  a = 1;
+%!  assert (1 && 0 && ++a, false)
+%!  assert (a, 1)
+## Level 2 (logical or)
+%!test
+%!  a = 1;
+%!  assert (0 || 1 || ++a, true)
+%!  assert (a, 1)
+## Level 1 (assignment)
 %!test
 %! a = 2; b = 5; c = 7;
 %! assert (a += b *= c += 1, 42)
 %! assert (b == 40 && c == 8)
+