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problem while adding 2 numbers (double)

 
sachin bal
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Hi,

I have developed the a small program to calculate the addition of 2 numbers which are double. There seems to be some problem with the output specifically for the following 2 numbers 10.4 and 19.05. The output which I get after adding these two numbers is 29.450000000000003.

In case I add 10.4 and 29.05, I get the output as 39.45.

Can someone help me understand the reason for this discrepancy?

Regards

Sachin Bal
 
Shinil Mohan
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Can you try using DecimalFormat for getting the output you are looking for.

http://download.oracle.com/javase/6/docs/api/java/text/DecimalFormat.html
 
Stephan van Hulst
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The reason is that floating point numbers can not represent every number exactly. They are generally an approximation of the actual number.

The two doubles both deviate a little bit from the real intended value, and when you add them, their deviation is added as well. In this particular case, the deviation becomes to big that it appears significant, and shows up in the output.
 
Rob Spoor
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Check out our JavaBeginnersFaq, item #20.
 
sachin bal
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Hi All,

Thank you for all the help. I appreciate it.

Regards

Sachin Bal
 
With a little knowledge, a cast iron skillet is non-stick and lasts a lifetime.
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