DAX - Why Does 3.3/1.1 = 2.9999999999999997?

[Anonymous]

Hi

I have a simple calculation which divides one number by a second number and then puts the result into buckets. However i have found results in the wrong bucket because some simple divisions are coming up with some strange answers.

I find that when using decimals some calculations don't come out correctly and therefore end up inthe wrong bucket. If you add this calculated column to any workbook

test_calc = DIVIDE(3.3,1.1) = 2.9999999999999997

you get the answer TRUE

because the bucket this calcuation should be in is equal to or greater than 3 it is falling in the wrong place.

Does anyone know why this happens, and any way to make this calculate correctly? Not looking for a work around (i.e. rounding), looking for understanding and/or solution.

[amitchandak]

I tried the same, but Power BI does not allow me to show more than 15 decimal places. So I am getting 3. In your case, it is 16.

I think this is true with all decimal place calculation. Ultimately these calculations happen in binary were decimal place has an accuracy level. 

[Anonymous]

It does display as 3 for me too, but if I try to use a logic operator it doesn't come out right. If you try a calculated column like 'test_calc = 3.3/1.1 = 3'. It will be False 

[amitchandak]

Please check

https://community.powerbi.com/t5/Desktop/Power-Query-decimal-precision-problem-does-not-get-to-0-whe...