Abs Bug

[User_Russian]

Of help.

Returns the absolute value. The return-value is always positive.

Why a negative result?

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z.l=Abs($80000000)
Debug z

This is a bug or function Abs() or inaccurate documentation.

[STARGÅTE]

The number from which to get the absolute value. This function will only work correctly with float numbers. With integers, it will fail if the integer is too large (due to a loss of precision).

[ts-soft]

You have to use a float or double for result, as documented:

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z.f=Abs($80000000)
Debug z 

[davido]

You could use a Macro. I use the following because it is faster than ABS():

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Macro iABS(i,ans)
  If i < 0
    ans = -i
  Else
    ans = i
  EndIf
EndMacro

EnableExplicit

Define c.i = -1234, M.i, p.i, dt = ElapsedMilliseconds()

For M = 1 To 10000000
iABS(c,p)
Next M

MessageRequester("Result: " + Str(p),"In: " + Str(ElapsedMilliseconds() - dt))

[freak]

The value is negative because it is too large to fit into a long. this has nothing to do with the ABS function.

Not a bug.

[User_Russian]

Strange logic!
This function is most needed for integer numbers than for floating numbers. Why not a similar function for integer variables?

Maybe you should reflect on adding unsigned variables?

[BasicallyPure]

It does work for integers but the hex value must be within the range of the variable type you are using.
The number you are using, $80000000, is larger than the maximum positive value for a long.
When you use $80000000 you set bit 32 to a one which is the sign bit.
$80000000 is a negative number.

Long | .l | 4 bytes | -2147483648 to +2147483647

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z.l = $7FFFFFFF
Debug z

z = $80000000
Debug z

BP

[Sicro]

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; min. Quad:       -9223372036854775808
Define.q Value = Abs(-77777777777777777)

Debug Value ; 77777777777777776

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Define.l Value

; min. Long:  -2147483648
Value =   Abs(-2147483648)
Debug Value ; -2147483648 => Because Overflow
Debug Bin(Value, #PB_Long) ; 10000000000000000000000000000000

; min. Long: -2147483648
Value =  Abs(-2147483647)
Debug Value ; 2147483647
Debug Bin(Value, #PB_Long) ; 1111111111111111111111111111111

Better use the command only with float variables, as documented.