Revision as of 16:52, 16 September 2017

$bitoff returns N with the Bth bit set to 0.

Synopsis

$bitoff(<N>,<B>)

Parameters

N = Base-10 Number in the range + 2^32-1 through -2^31+1
B = Counting from the right-most bit, the bit position to set as 0

Properties

None

Example

//var %n 10 | echo -a $bitoff(%n,2)
; returns 8

Here's how the answer was calculated:

1. Convert base-10 N to binary.
2. Count 2 from the right
3. That bit is set to 0
4. Return the possibly altered number

//var %n 10 | echo -a $base(%n,10,2,32) | echo -a $str(-,24) $+ 87654321 | echo -a $base($bitoff(%n,2),10,2,32) $base(1000,2,10)
; returns:
00000000000000000000000000001010
------------------------87654321
00000000000000000000000000001000 8

If N is 2^32 or greater, returns 2^32 -1
If N is less than -2^31+1, returns 2^(B-1) +1

Using $biton and $bitoff, you can store several variables as bits within a single variable, instead of creating a separate variable for each.
The /window switch -wN uses bit settings, with default 3 if N not used.

var %treebarsetting $true
var %switchbarsetting $true
var %n
if (%switchbarsetting) var %n $biton(%n,1)
if (%treebarsetting) var %n $biton(%n,2)
if (%n == $null) var %n 3

Compatibility

Added: mIRC v5.61
Added on: 23 Sep 1999
Note: Unless otherwise stated, this was the date of original functionality.
Further enhancements may have been made in later versions.

See also

• $xor
• $or
• $and
• $not
• $biton
• $isbit
• List of identifiers - mIRC