ROUND problem

Question

Post reply

ROUND problem

luissantos

SSCertifiable

Points: 7385
More actions
April 15, 2008 at 5:52 am

#185328

Hello Comunity
I have the following ROUND problem
my value : 326,760000
i need this calculation 326,760000*1.105/1.21
the value of : 326,760000*1.105 = 361,070
if i divide by 1.21 , the result is : 298.405
I want to make ROUND for the final result is equal to : 298.41
i test some round position:
round(etiliquido*1.105,2) return 361,070, but if i make
round(etiliquido*1.105,2) / 1.21 = 298,4049586776859
or
round(round(etiliquido*1.105,2)/1.21,2) = 298.40
Someone could help me
Many Thanks
Luis Santos

Viewing 5 posts - 1 through 4 (of 4 total)

You must be logged in to reply to this topic. Login to reply

Jeremy-475548 Hall of Fame Points: 3035 More actions · Answer 1

Hmmm...

Does this article put you on the right track?

http://qa.sqlservercentral.com/articles/Advanced+Querying/afixfunctionintsql/2487/

It seems like you are dealing with significant digits in scientific calculations.

This function in particular just calculates 2 significant digits, but perhaps could be modified to suit your needs.

SwePeso SSC-Dedicated Points: 39725 More actions · Answer 2

SELECT326.76 * 1.105 / 1.21,

CEILING(326.76 * 1.105 / 1.21 * 100.0) / 100

N 56°04'39.16"
E 12°55'05.25"

Matt Miller (4) SSC Guru Points: 124210 More actions · Answer 3

There's something flawed in your math -

326.760000*1.105 = 361.070 is not true. 361.0698 is the actual number.

You can't round "mid operations" unless you plan on introducing large errors into your result. This will get you into large amounts of errors. You gotta go back and revisit all of those yucky "scientific precision" classes we all slept through in high school. Round mid-stream and you wouldn't hit the side of a barn with the precision issues you put in.

I know what you'd "like" to see - but it's not the correct result.

----------------------------------------------------------------------------------
Your lack of planning does not constitute an emergency on my part...unless you're my manager...or a director and above...or a really loud-spoken end-user..All right - what was my emergency again?

luissantos SSCertifiable Points: 7385 More actions · Answer 4

Hello Matt

I make the calc on a small calculator, and you have reason about your result, but i solve my problem using :

round(round(cast(etiliquido*1.105 as decimal(10,2))/1.21,3),2)

Many thanks

Luis Santos