Merge pull request #1354 from mathics/combinatorica-2.0-prereqs

Go over Quiet, All, and Part docs

Author: rocky

mathics/builtin/inout.py

@@ -1516,9 +1516,18 @@ class Quiet(Builtin):
         <dd>evaluates $expr$, with messages $off$ being suppressed, but messages $on$ being displayed.
     </dl>
 
+    Evaluate without generating messages:
+    >> Quiet[1/0]
+     = ComplexInfinity
+
+    Same as above:
+    >> Quiet[1/0, All]
+     = ComplexInfinity
+
     >> a::b = "Hello";
     >> Quiet[x+x, {a::b}]
      = 2 x
+
     >> Quiet[Message[a::b]; x+x, {a::b}]
      = 2 x
 
@@ -1527,7 +1536,7 @@ class Quiet(Builtin):
      : Hello
      = 2 x
 
-    >> Quiet[expr, All, All]
+    #> Quiet[expr, All, All]
      : Arguments 2 and 3 of Quiet[expr, All, All] should not both be All.
      = Quiet[expr, All, All]
     >> Quiet[x + x, {a::b}, {a::b}]

mathics/builtin/lists.py

@@ -379,8 +379,8 @@ def apply(self, expr, evaluation):
 class All(Predefined):
     """
     <dl>
-    <dt>'All'
-        <dd>is a possible value for 'Span' and 'Quiet'.
+      <dt>'All'
+      <dd>is a possible option value for 'Span', 'Quiet', 'Part' and related functions. 'All' specifies all parts at a particular level.
     </dl>
     """
 
@@ -991,8 +991,8 @@ def convert_seq(seq):
 class Part(Builtin):
     """
     <dl>
-    <dt>'Part[$expr$, $i$]'
-        <dd>returns part $i$ of $expr$.
+      <dt>'Part[$expr$, $i$]'
+      <dd>returns part $i$ of $expr$.
     </dl>
 
     Extract an element from a list:
@@ -1030,11 +1030,17 @@ class Part(Builtin):
     >> B = {{a, b, c}, {d, e, f}, {g, h, i}};
     >> B[[;;, 2]]
      = {b, e, h}
+
     Extract a submatrix of 1st and 3rd row and the two last columns:
     >> B = {{1, 2, 3}, {4, 5, 6}, {7, 8, 9}};
+
     >> B[[{1, 3}, -2;;-1]]
      = {{2, 3}, {8, 9}}
 
+    The 3d column of a matrix:
+    >> {{a, b, c}, {d, e, f}, {g, h, i}}[[All, 3]]
+     = {c, f, i}
+
     Further examples:
     >> (a+b+c+d)[[-1;;-2]]
      = 0