(maxima.info)Relational operators

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7.3 Relational operators
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 -- Operator: <
 -- Operator: <=
 -- Operator: >=
 -- Operator: >

     The symbols '<' '<=' '>=' and '>' represent less than, less than or
     equal, greater than or equal, and greater than, respectively.  The
     names of these operators are '"<"' '"<="' '">="' and '">"', which
     may appear where the name of a function or operator is required.

     These relational operators are all binary operators; constructs
     such as 'a < b < c' are not recognized by Maxima.

     Relational expressions are evaluated to Boolean values by the
     functions 'is' and 'maybe', and the programming constructs 'if',
     'while', and 'unless'.  Relational expressions are not otherwise
     evaluated or simplified to Boolean values, although the arguments
     of relational expressions are evaluated (when evaluation is not
     otherwise prevented by quotation).

     When a relational expression cannot be evaluated to 'true' or
     'false', the behavior of 'is' and 'if' are governed by the global
     flag 'prederror'.  When 'prederror' is 'true', 'is' and 'if'
     trigger an error.  When 'prederror' is 'false', 'is' returns
     'unknown', and 'if' returns a partially-evaluated conditional
     expression.

     'maybe' always behaves as if 'prederror' were 'false', and 'while'
     and 'unless' always behave as if 'prederror' were 'true'.

     Relational operators do not distribute over lists or other
     aggregates.

     See also '=', '#', 'equal', and 'notequal'.

     Examples:

     Relational expressions are evaluated to Boolean values by some
     functions and programming constructs.

          (%i1) [x, y, z] : [123, 456, 789];
          (%o1)                    [123, 456, 789]
          (%i2) is (x < y);
          (%o2)                         true
          (%i3) maybe (y > z);
          (%o3)                         false
          (%i4) if x >= z then 1 else 0;
          (%o4)                           0
          (%i5) block ([S], S : 0, for i:1 while i <= 100 do S : S + i,
                       return (S));
          (%o5)                         5050

     Relational expressions are not otherwise evaluated or simplified to
     Boolean values, although the arguments of relational expressions
     are evaluated.

          (%o1)                    [123, 456, 789]
          (%i2) [x < y, y <= z, z >= y, y > z];
          (%o2)    [123 < 456, 456 <= 789, 789 >= 456, 456 > 789]
          (%i3) map (is, %);
          (%o3)               [true, true, true, false]