April 27, 2015

# Mathematical Functions

#\$DifferenceFn   subtraction

An instance of both #\$BinaryFunction and #\$EvaluatableFunction. When applied to an instance MINUEND of #\$ScalarInterval and an instance SUBTRAHEND of #\$ScalarInterval, #\$DifferenceFn yields an instance of #\$ScalarInterval that is the result of subtracting SUBTRAHEND from MINUEND. For example, (#\$DifferenceFn 88 11) is 77 and (#\$DifferenceFn (#\$Kilogram 4.2) (#\$Kilogram 3)) is (#\$Kilogram 1.2). Note that when MINUEND is an instance of a specialization SCALAR-1 of #\$ScalarInterval, SUBTRAHEND is an instance of a specialization SCALAR-2 of #\$ScalarInterval, and neither (#\$genls SCALAR-1 SCALAR-2) nor (#\$genls SCALAR-2 SCALAR-1) holds, then (#\$DifferenceFn MINUEND SUBTRAHEND) is undefined. For example, (#\$DifferenceFn (#\$MinutesDuration 1) (#\$Meter 3)) is undefined, since (#\$MinutesDuration 1) is an instance of #\$Time-Quantity and (#\$Meter 3) is an instance of #\$Distance.

direct instance of: #\$FunctionFromQuantitiesToQuantities #\$PartialDenotationalFunction #\$BinaryFunction #\$Individual

#\$PlusFn   plus fn    **GAFs NOT REVIEWED**

A #\$VariableArityRelation which represents addition in Cyc. (#\$PlusFn ADDEND1 ADDEND2 …) yields a quantity which is the result of adding ADDEND1 ADDEND2 (…) together. All of the arguments to #\$PlusFn must be instances of #\$ScalarInterval, as is its result. Examples: (#\$PlusFn 2 3 4) returns 9; (#\$PlusFn (#\$Meter 1.5) (#\$Meter 0.7)) returns (#\$Meter 2.2). For subtraction, see #\$DifferenceFn.