permaculture playing cards*
The moose likes Java in General and the fly likes Arithmatic calculations using Big Decimals Big Moose Saloon
  Search | Java FAQ | Recent Topics | Flagged Topics | Hot Topics | Zero Replies
Register / Login


Win a copy of Murach's Java Servlets and JSP this week in the Servlets forum!
JavaRanch » Java Forums » Java » Java in General
Bookmark "Arithmatic calculations using Big Decimals" Watch "Arithmatic calculations using Big Decimals" New topic
Author

Arithmatic calculations using Big Decimals

Huma Rangwani
Greenhorn

Joined: Oct 09, 2012
Posts: 1
Hi

I have a calculation using big decimal values x, y=7888 and z= 4902 as below:
x = (y * 1000 / z)
I get arithmatic error as "Non-terminating decimal expansion" without rounding up. But the required result is 1609.13913, where as with calculation below I am getting result as 1609.15200.
System.out.println(new BigDecimal("7888").multiply(new BigDecimal("1000").divide(new BigDecimal("4902"),5,BigDecimal.ROUND_HALF_UP)));
Even as I use:
System.out.println(new BigDecimal("7888").multiply(new BigDecimal("1000").divide(new BigDecimal("4902"),11,BigDecimal.ROUND_HALF_UP)));
The result is coming as 1609.13912686288.
Winston Gutkowski
Bartender

Joined: Mar 17, 2011
Posts: 7492
    
  18

Huma Rangwani wrote:I get arithmatic error as "Non-terminating decimal expansion" without rounding up.

Which simply means that the result cannot be represented by a decimal number (which is quite often the case).

But the required result is 1609.13913, where as with calculation below I am getting result as 1609.15200.
System.out.println(new BigDecimal("7888").multiply(new BigDecimal("1000").divide(new BigDecimal("4902"),5,BigDecimal.ROUND_HALF_UP)));

And that's because your bracketing is wrong. In cases like this it's usually a good idea to write "dumb" code, and spread things out a bit, rather than piling everything together in one statement, viz:and now look at your statement:NOW do you see where the problem is?

Winston


Isn't it funny how there's always time and money enough to do it WRONG?
Articles by Winston can be found here
 
I agree. Here's the link: http://aspose.com/file-tools
 
subject: Arithmatic calculations using Big Decimals
 
Similar Threads
BigDecimal ROUND_HALF_EVEN rounding mode and the number of digits to the right of the decimal point
regarding bigdecimal.divide problem
Math Precision - Calculator
Rounding BigDecimal Calculation Yielded Wrong Result
Trouble with BigDecimal and Double