cancel
Showing results for 
Search instead for 
Did you mean: 
Reply
bkornfuehrer
New Member

RoundDown incorrect in certain instances

I found some very interesting RoundDown behavior and looking for some perspective here.

 

The initial number which sparked this was 17240.17. When entered into RoundDown(17240.17, 2) the result is 17240.16

 

This happens for .19, .26, and .35 as well. To add one final wrinkle this seems to happen only on whole numbers from 16384.17 and 20971.17

 

I appreciate any feedback on this. In the meantime I am using RoundDown(17240.17, 3) which seems to be working correctly

 

Thanks!

1 ACCEPTED SOLUTION

Accepted Solutions
v-bofeng-msft
Community Support
Community Support

Hi @bkornfuehrer :

  The point is Floating-point arithmetic is approximate, so it can sometimes give unexpected results with many documented examples. For example,you might expect the formula 55 / 100 * 100 to return exactly 55 and RoundUp((55 / 100 * 100) - 55,0) to return exactly zero. However, the latter formula returns 1.Because (55 / 100 * 100) - 55 returns  7.1054 x 10–15, which is very small but not zero. 

  I think this link will help you a lot:

  Number and Currency

Best Regards,

Bof

View solution in original post

1 REPLY 1
v-bofeng-msft
Community Support
Community Support

Hi @bkornfuehrer :

  The point is Floating-point arithmetic is approximate, so it can sometimes give unexpected results with many documented examples. For example,you might expect the formula 55 / 100 * 100 to return exactly 55 and RoundUp((55 / 100 * 100) - 55,0) to return exactly zero. However, the latter formula returns 1.Because (55 / 100 * 100) - 55 returns  7.1054 x 10–15, which is very small but not zero. 

  I think this link will help you a lot:

  Number and Currency

Best Regards,

Bof

Helpful resources

Announcements
Power Apps News & Annoucements carousel

Power Apps News & Announcements

Keep up to date with current events and community announcements in the Power Apps community.

Community Call Conversations

Introducing the Community Calls Conversations

A great place where you can stay up to date with community calls and interact with the speakers.

Power Apps Community Blog Carousel

Power Apps Community Blog

Check out the latest Community Blog from the community!

Top Solution Authors
Top Kudoed Authors
Users online (6,620)