How to generate a random float number in Objective-C with min and max?

Question

Possible Duplicates:
Generating Random Numbers in Objective-C
What's the most optimal way to get a random floatingpoint number between floatA and floatB?

Hi,

I want to generate a random float number like

float scale = randFloat(0.5f, 2.0f);

How do I do this in objective-c?

This answer does not help me! – DarkLeafyGreen May 19 '11 at 05:25 — DarkLeafyGreen, May 19 '11 at 05:25
perhaps you could explain why.... – Mitch Wheat May 19 '11 at 05:26 — Mitch Wheat, May 19 '11 at 05:26
Maybe because the answer is returning an int. – chrs Mar 10 '14 at 03:42 — chrs, Mar 10 '14 at 03:42

score 4 · Accepted Answer · answered May 19 '11 at 05:26

4

Here is how you generate them :

// Get random value between 0 and 99
int x = arc4random() % 100;

// Get random number between 500 and 1000
int y =  (arc4random() % 501) + 500);

You can easily extend this for any range you need.

Hope that helps.

answered May 19 '11 at 05:26

Shaunak

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score 1 · Answer 2 · answered May 19 '11 at 05:37

Generate two random integers and divide one by the other. With some manipulation you can introduce a range.

Also, depending on the required resolution you could simply generate a single random integer and divide it by a fixed integer to get your float. For example, generate a random number between 0 and 100,000 and divide it by 100,000. You can offset and shift the result around to get the range you need.

How to generate a random float number in Objective-C with min and max?

2 Answers2