Give your Commodore 64 new life with an SD card reader
Dust off your old Commodore 64, and you could be the coolest kid on the block by plugging SD cards into it instead of floppies.
0, 1, Many, a Zillion
Posted twelve years ago
There are only four numbers in computer programs:
0, 1, many, "a zillion"
If you have 2 or more of anything, you are, in general, better off using loops to process many of them.
But what is "a zillion?"
Zillion is a made-up number. Your system cannot hold a zillion items in memory. It cannot show a zillion items on the screen.
Doesn't work for "a zillion":
Select employee name:
Doesn't work for "a zillion":
def handleFiles( filenames: Array[String] ) {
val results = openFiles(filenames).readAll().processAll()
results
}
* The program first opens all the files, and then processes them. The OS will run out of file handles.
Doesn't work for "a zillion":
Changing software from handling "many" to "a zillion" is hard if the program is already written.
Decide when you need to handle a zillion.
Steve Hanov makes a living working on
Rhymebrain.com,
rapt.ink,
www.websequencediagrams.com,
and Zwibbler.com. He lives in
Waterloo, Canada.
Post comment
edit
Andy Brice
eleven years ago
I find a bigger problem is when you decide part way through a design that you need to go from 1 to many. That can be a real headache.
edit
Dan
twelve years ago
I agree with Roland:
Try:
None, some, lots, zillions.
None: I don't need to worry about this.
Some: I don't need to be clever about this.
Lots: I need to be clever about this.
Zillions: I need to be very clever about this.
Consider the read & process example:
None: No files. Nothing to do.
Some: The naive approach above is fine.
Lots: OK so we need to read, process & discard in a loop.
Zillions: We need to implement multi-threading to avoid bottle-necks... (or whatever technological limitation you're pushing against).
Steve McConnell talks about the difference between application development and R&D.
R&D is the never done before & not sure it can be done domain of 'zillions'.
edit
Roland
twelve years ago
From my software development experience, I would include the numbers: 2 & Several.
Two: Is basically a simple conditional.
Several: Is 3 or more, but less than 'Many'. This is basically a CASE, simple loop or drop down list.
I make the distinction between 2 and 3 because it is at this point you have to start thinking differently about how you approach a problem and the algorithm's you will use.
Otherwise totally agree.
Dust off your old Commodore 64, and you could be the coolest kid on the block by plugging SD cards into it instead of floppies.
Why Perforce is more scalable than Git
Branching on Perforce is kind of like performing open heart surgery. But here's why git can't hope to compete with it.Exploiting perceptual colour difference for edge detection
Think colour isn't important in image processing algorithms? Let's try it both ways, and see for yourself.
Experiment: Deleting a post from the Internet
Once you post something on the Internet, it is hard to get rid of it. As an experiment, I deleted one of my past posts, and I tried to remove all traces of it.