Mathematical calculations using BigDecimal

Hi all,
I am doing some mathematical calculations using float variables. They are not working properly because of rounding issues....So, before I change the whole program to do the same calculations using BigDecimal, just wanted to check out whether there are any catches in that also. Like, is it safe if I do BigDecimal.add, subract etc. instead of addding the floating point numbers directly.....Can I be assured that the results will be precise, to 2 decimal places?
Any help will be appreciated...
Thanks

The "catch" is that computers do not work with real numbers. They work with representations of real numbers like finite decimals or fractions. My advice is to continue to use doubles, but do not expect infinitely precise results and round the values when outputting them.

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Can I perform mathematical calculations in ABAP Query?
Kingly guide
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You would need tables - AFPO, AUFM, MSEG, MAKTX (if you need mtl description).
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I was using Gregory-Leibniz series to calculate PI = 4 - 4/3 + 4/5 - 4/7 + 4/9 - 4/11 + ...
Something like:
double pi = 0.0;
       int limit = 3000000;
       for (int i = 0, y = 1; i <= limit; y+=2, i++)
                 if (y == 1)
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I realize that when I do the 4/y calculations involving both doubles... the result is probably stored according to the IEEE standards which is the thing to avoid... Is that correct? Is my PI result going to be accurate?
I noticed with this one decimals up to the 22nd place are all filled with some numbers in the calculations compared with the first one involving only double number calculations which had zero's starting around the 15th decimal.
Something like doesn't work and ends up with arithmeticexceptions...
pi = pi.subtract(new BigDecimal("4").divide(new BigDecimal(Integer.toString(y))));
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quoting from the API documentation on BigDecimal
"The BigDecimal class gives its user complete control over rounding behavior. If no rounding mode is specified and the exact result cannot be represented, an exception is thrown; otherwise, calculations can be carried out to a chosen precision and rounding mode by supplying an appropriate MathContext object to the operation."
That explains the arithmetic exceptions.
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A little reading and possibly re-reading of the documentation will help in the understanding of the BigDecimal class.

Looking for examples using BigDecimal

Two newbies to Java are looking for examples of code that use the BigDecimal features for rounding and truncating large numbers to more user-friendly values.
We are doing some hefty math calculations on values defined as doubles and want to round and truncate to within 1/100th for display purposes.
We've tried some stuff on our own, but it is not cooperating. Any help would be greatly appreciated!

Here is a good article of how to use BigDecimal
http://www.javaworld.com/javaworld/jw-06-2001/jw-0601-cents.html
Hope this helps

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assuming you missed parens (as others assumed), and you really meant
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then the answer is
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the proof is:
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remove X to the outside:
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simplify:
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S(z-1) = 1 - z^-n
S = (1 - z^-n) / (z-1)
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Hi
Welcome to SDN.
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Hi,
Create push buttons for the + , - , / , * , = in your dialog program.
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ADDITION
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MULTIPLICATION
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I was interested to have the following getNumberOfDecimalPlace function :
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System.out.println("1.0 = " + Utils.getNumberOfDecimalPlace(1.0)); // 0
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Please [don't cross-post!|http://stackoverflow.com/questions/2296110/determine-number-of-decimal-place-using-bigdecimal], it's considered rude. If you must do it, then at least link each post so that people can find out which answers you've already got in order to avoid duplicate work on our part.
Please read [_How To Ask Questions The Smart Way_|http://www.catb.org/~esr/faqs/smart-questions.html].

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Mathematical calculations using BigDecimal

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