Number API Functions
This document lists most useful (and most often needed) functions. Be aware, that there are many more to be found in either the class references or via the builtin class browser.
Reference: Integer Float Fraction FixedPoint Complex which all inherit from Number
Inhaltsverzeichnis
Testing[Bearbeiten]
Check if number is not infinity and not NaN:
aNumber isFinite => Boolean
Check if number is either positive infinity (INF) or negative infinity (-INF):
aNumber isInfinite => Boolean
Check if number is NaN ("Not a Number"):
aNumber isNaN => Boolean
Sign checks[Bearbeiten]
aNumber negative => Boolean
same as aNumber < 0
aNumber positive => Boolean
same as aNumber >= 0
aNumber strictlyPositive => Boolean
same as aNumber > 0
Misc Properties[Bearbeiten]
anInteger isPrime => Boolean
true if the number is a prime number
anInteger isPowerOf2 => Boolean
true if there exists an n, such that 2ˆn equals the number
anInteger isPowerOf:b => Boolean
true if there exists an n, such that bˆn equals the number
Queries[Bearbeiten]
anInteger nextPrime => anInteger anInteger nextPowerOf2 => anInteger
Arithmetic[Bearbeiten]
The usual arithmetic operators.
Notice, that they are evaluated left to right, without special precedences.
Thus you should always use parentheses to group expressions when there are two or more operators in an arithmetic expression.
aNumber + aNumber => Number aNumber - aNumber => Number aNumber * aNumber => Number aNumber / aNumber => Number
Truncated result (towards the next smaller integer i.e. towards negative infinity):
aNumber // aNumber => Integer
Examples:
100 // 3 => 33
-100 // 3 => -34
Trigonometric and Mathematical Functions[Bearbeiten]
The usual operations are provided as unary messages to the number:
aNumber sin => Number aNumber log => Number
Printing[Bearbeiten]
Numbers can print themself on an output stream,
aNumber printOn: aStream
or convert themself to a string:
aNumber printString => String
The above generate a standard format, which should fit most needs.
More control is available via the printf functions, which offer a range of options to fill left or right, to control printing of the sign and to fill with zeros.
The printf:on: function:
formatString printf: { aNumber } on: aStream
takes an argument Vector as first Argument; thus, multiple values are printed as in the following example:
'%04x %3d %4.3f' printf:{ 123 . 4 . 3.14159 } on:Transcript
Individual conversions can be done with:
aNumber printfPrintString: formatString => String