random thoughts
Monday, 7. November 2005

a question of masks

I am quite comfortable with the idea of using bit masks to test variables for specific values. What came up the other day is the need to test a byte for the presence of only a single set bit, where the specific bit is not known.

I wanted to know whether the byte had any of the following values, without caring what the actual value was;

    00000001
    00000010
    00000100
    00001000
    00010000
    00100000
    01000000

The consensus from everyone I've discussed this with is that a loop with multiple tests is required, but I can't help thinking that out there somewhere is someone that has a clever bit mask or mathematical way to test for this with a single expression.

Online for 5568 days
Last update: 12/10/10 9:58 AM
status
Youre not logged in ... Login
menu
... home
... topics
... galleries
... Home
... Tags


... Antville.org home
my other sites
search
calendar
October 2017
SunMonTueWedThuFriSat
1234567
891011121314
15161718192021
22232425262728
293031
December
recent updates
moving on I have succumbed
to the lure of Wordpress and have started a new...
by craniac (12/9/05 5:22 PM)
kill or cure According to
this blog entry the uninstaller that Sony has made available...
by craniac (11/16/05 11:44 AM)
sory seems to be the
hardest word In response to the Sony DRM fiasco, someone...
by craniac (11/16/05 10:49 AM)
a new internet Many years
ago I worked for a small software development company. Let's...
by craniac (11/7/05 10:03 AM)
a question of masks I
am quite comfortable with the idea of using bit masks...
by craniac (11/7/05 8:50 AM)
boycott sony! Dave Slusher over
on Evil Genius Chronicles is calling for a boycott of...
by craniac (11/4/05 11:06 AM)
car guards Here in South
Africa car theft is a big problem so every parking...
by craniac (11/4/05 9:47 AM)
pseudonym I just received a
spam e-mail from someone calling himself (or herself) Maltreatment U....
by craniac (11/2/05 1:39 PM)
the cry of the larger
breasted woman Originally posted by taminator
by craniac (10/25/05 8:59 AM)
young entrepreneur A friend sent
me this photo, which I thought was really funny.
by craniac (10/19/05 4:13 PM)

RSS Feed

Made with Antville

Creative Commons License
This work is licensed under a Creative Commons License.