src/swipl-devel/packages/xpce/man/refmanual/md/real.md

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class real {#class-real}

A real object represents a floating point number in PCE. As PCE is designed first of all for developing user interfaces, reals are rarely used and therefore represented as true objects. The behaviour of reals is very similar to the behaviour of class number.

The value of a real object is represented as a double-precision float using the native floating point format of the machine.

@see class binary_expression

Send methods {#class-real-send}

• real->minus: real Subtract argument from value.

• real->plus: real Add argument to value.

• real->times: real Multiply value by argument.

• real->divide: real Basic arithmetic operations. Note that possible resulting floating point exceptions are not handled gracefully in the current implementation.

• real->equal: real Test if equal to argument.

• real->larger_equal: real Test if larger-or-equal than argument.

• real->less_equal: real Test if less-or-equal than argument.

• real->not_equal: real Test if not-equal to argument.

• real->smaller: real Test if less than argument.

• real->larger: real Compare the receiver's <-value to the <-value of the argument. It ->larger succeeds, the receiver is larger than the argument. Note that type conversion allows for the comparison of integers and numbers too.

• real->value: real Copy the <-value from the <-value of the argument.

Get methods {#class-real-get}

• real<-catch_all: selector=name, argument=unchecked ... -> copy=real Non-destructive arithmetic. Create a new real object with the same <-value, execute the operation and, if the operation succeeds, return the new real. See also number <-catch_all.

• real<-value: -> real Equivalent to <-self.

  Bugs: It might be better to return a copy.

rswipl documentation built on June 16, 2026, 5:07 p.m.