1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44

The file SHARE1;INEQ FASL contains a number of automatic simplifications
for manipulating inequalities. Be careful about using parentheses
around the inequalities: when the user types in (A>B)+(C=5) the
result is A+C>B+5; but A>B+C=5 is a syntax error; and (A>B+C)=5 is
something else entirely. Do DISPRULE(ALL); to see a complete listing
of the rule definitions. The user will be queried if MACSYMA is
unable to decide the sign of a quantity multiplying an inequality.
The most common misfeature is illustrated by:
eq:a>b;
2*eq;
%eq;
Another problem is 0 times an inequality; the default to have this
turn into 0 has been left alone. However, if you type
X*(some inequality); and MACSYMA asks about the sign of X and you
respond ZERO; (or Z;), the program will return X*(some inequality)
and not use the info that X is 0. You should do EV(%,X:0) in such
a case, as the database will only be used for comparison purposes
in decisions, and not for the purpose of evaluating X.
[Thus, INTEGRATE((I+1)*X^I,X); will ask about I+1 being zero or non
zero, and if you say Z;, the answer is (I+1)*LOG(X), so the decision
in INTEGRATE made use of the information, while (I+1) was not
evaluated.]
The user may note a slower response when this package is loaded, as
the simplifier is forced to examine more rules than without the
package, so you might wish to remove the rules after making use of
them. Do KILL(RULES); to eliminate all of the RULES (including any
that you might have defined); or you may be more selective by
KILL'ing only some of them; or use REMRULE on a specific rule.
*** Note that if you load this package after defining your own ***
rules you will clobber your rules that have the same name. The
rules in this package are:
*RULE1 ... *RULE8 +RULE1 ... +RULE18
and you must enclose the rulename in quotes to refer to it, as
in REMRULE("+","+RULE1"); to specifically remove the first rule
on "+" (capital letters in the name are essential, also), or
DISPRULE("*RULE2"); to display the definition of the second
multiplicative rule.
Suggestions, comments, and bugs to LPH@MITMC.
Leo P. Harten May 12, 1983
