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Sgnfunction

Returns the sign part of a number

Mathematical Functionsfunctiondocumented

Syntax

Declare Function Sgn ( ByVal number As numtype ) As numtype

Parameters

NameDescription
numberthe number to find the sign of
numtypea numeric type

Return value


Returns the sign part of number.
  • If number is greater than zero, then Sgn returns 1.
  • If number is equal to zero, then Sgn returns 0.
  • If number is less than zero, then Sgn returns -1.

Description


The required number argument can be any valid numeric expression.
Unsigned numbers of size greater than or equal to SizeOf(Any Ptr) will be treated as if they were signed, i.e. if the highest bit is set the number will be treated as negative, and -1 will be returned.

Note:
The return type of Sgn depends on the type of the passed argument (variable or constant, its data type), and of the used backend (gas, gas64, gcc 32-bit, gcc 64-bit):
- Sgn return type for a variable passed as argument:
Argument gas (32-bit) gas64 (64-bit) gcc 32-bit (*) gcc 64-bit (*)
[U]BYTE variable INTEGER INTEGER LONG LONG
[U]SHORT variable INTEGER INTEGER LONG LONG
[U]LONG variable INTEGER INTEGER LONG LONG
[U]INTEGER variable INTEGER INTEGER LONG LONG
[U]LONGINT variable LONGINT INTEGER LONG LONG
SINGLE variable SINGLE LONG LONG LONG
DOUBLE variable DOUBLE LONG LONG LONG

- Sgn return type for a constant passed as argument:
Argument gas (32-bit) gas64 (64-bit) gcc 32-bit (*) gcc 64-bit (*)
[U]BYTE constant INTEGER INTEGER INTEGER INTEGER
[U]SHORT constant INTEGER INTEGER INTEGER INTEGER
[U]LONG constant INTEGER INTEGER INTEGER INTEGER
[U]INTEGER constant INTEGER INTEGER INTEGER INTEGER
[U]LONGINT constant LONGINT INTEGER LONGINT INTEGER
SINGLE constant SINGLE SINGLE SINGLE SINGLE
DOUBLE constant DOUBLE DOUBLE DOUBLE DOUBLE

(*): applicable also for clang and llvm

The Sgn unary Operator can be overloaded with user defined types.

Remarks

Usage


result = Sgn( number )

Dialect Differences


  • In the -lang qb dialect, this operator cannot be overloaded.

Differences from QB


  • None

See also


Example


Dim N As Integer = 0



Print Sgn ( -1.87 )

Print Sgn ( 0 )

Print Sgn ( 42.658 )

Print Sgn ( N )

The output would look like:
-1
0
1
0

Reference

  • Documented in KeyPgSgn.html