PLOGHELP MINUS Kathryn Seifert October 1986
Operator to subtract one number from another
?- X is - .
Keywords: subtraction, arithmetic expressions, arithmetic, evaluation
To subtract one number from another, use the minus sign, with the
operator "is":
?- X is 2 - 1.
X = 1 ?
You can negate numbers too:
?- X is 3, Y is -X.
X = 3
Y = -3 ?
-- RELATED DOCUMENTATION -----------------------------------------------
PLOGHELP * ARITHMETIC
Overview of HELP files dealing with operations on numbers.
PLOGHELP * IS
Evaluating POP-11 and arithmetic expressions which return one result
PLOGHELP * SYMBOLS
Summary and index of HELP files for symbols used in Prolog
PLOGHELP * OPERATORS
Operator declarations made when the Prolog system is loaded
PLOGHELP * OP
How to declare operators