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Float Double numbers

cornel jew
Ranch Hand

Joined: Jul 13, 2002
Posts: 37
Hi all
Is there perhaps a way to get grip of the following :Float/Double MAX_MIN VALUES,POSITVE/NEGATIVE_INFINITY,NAN casting to int /float type etc, and using MATH methods on them.
It is very confusing remembering all the different results, i forgot sometimes what is what.
If anyone can perhaps explain the workings around it it will help, cos memorising this makes it difficult.
I have done a lot of mock questions, but hey i don't feel confident with it.
Thanks for any help.
Dirk Schreckmann

Joined: Dec 10, 2001
Posts: 7023
What do you mean exactly by "get grip"?
[ May 18, 2003: Message edited by: Dirk Schreckmann ]

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cornel jew
Ranch Hand

Joined: Jul 13, 2002
Posts: 37
Like doing arithmetic or casting operations for instance:
int i = (int)Float/Double.MIN/MAX_VALUE
float f = Float.NEGATIVE_INFINTY
int i = Math.round(f) etc.
Not to talk about using % / etc on them.
Maybe if i understand how double and float works i will understand.
I was doing a mock exam of Dan's operators and that was the type of questions which was asked.
Hope this will give you more info.
Thanks for the reply
Layne Lund
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Joined: Dec 06, 2001
Posts: 3061
Honestly, I only have a vague idea of what you are talking about. I don't spend my time memorizing the Java API. If I need to use something, I look it up in the API docs. Eventually, I know some basics about several classes by using them over and over in actual programs. I honestly don't think an abstract description will be much help. You just have to use it in a program to see how it can be used
In this particular instance, I can't think of any meaningful examples where to use these constants from the Float and Double classes. I think all of them are often used for error checking, especially NAN and POSITIVE/NETAGIVE_INFINITY. Here is some pseudocode that can illustrate this:

I don't think I can be any more specific than that at the moment. Perhaps you should get a book, such as Core Java, that shows some examples of how to use such members of the API classes.

Java API Documentation
The Java Tutorial
I agree. Here's the link:
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