I'm trying to round down a number to the nearest say 15, 20, 30. ie

726 to the nearest 30 is 700

714 to the nearest 15 is 700 etc

VBScript code would be very helpful but pseudocode would also be a huge help!

EDIT: Sorry, I forgot to say, that 726 is really a time expressed as an int, ie 07:26. So this should be 07:00, not 690

EDIT Again: I'm just extracting the minute and using the code people have answered with. Hopefully this will help someone else too. Thanks!

Thanks

I'm trying to round down a number to the nearest say 15, 20, 30. ie

726 to the nearest 30 is 700

714 to the nearest 15 is 700 etc

VBScript code would be very helpful but pseudocode would also be a huge help!

EDIT: Sorry, I forgot to say, that 726 is really a time expressed as an int, ie 07:26. So this should be 07:00, not 690

EDIT Again: I'm just extracting the minute and using the code people have answered with. Hopefully this will help someone else too. Thanks!

Thanks

• javascript
• vbscript
• rounding

• I think you mean 726 (rounded down) to the nearest 30 is 720 and 714 (rounded down) to the nearest 15 is 705. – Daniel Renshaw Commented Aug 16, 2010 at 16:16
• Yes I forgot to mention that its really times, please see the question. Really sorry, my mistake – Igor K Commented Aug 16, 2010 at 16:23
• can you please further clarify how time like 5:45pm would appear in your int representation and if the last 2 digits are ever over 59... – Oded Commented Aug 16, 2010 at 16:26
• Thanks Oded, all sorted with your original code – Igor K Commented Aug 16, 2010 at 16:28

3 Answers 3

Pseudo code:

diff = num mod nearest
return num - diff

So 726 mod 30 = 6

726 - 6 = 720

vbscript:

Function GetNearest(num, nearest)
    Dim diff = num mod nearest
    GetNearest = num - diff
End Function

You listed a bunch of languages in your tags. I'm going with C#, but a more generic algorithm:

int n = 726;
int q = 30;
int r = Math.Floor(n / q) * q;

another way to do it is just to use integer division: 726 / 30 * 30 = 720