Precision -Pimpy needs help

[Pimpya]

using System;

public class Pimpy
{
   public static void Main(String []a)
   {
       Double d=100.123456789123456789123456789123456789;
       Console.Writeline("{0}",d); 
   }
} 

I'd like the output to be decimally correct as defined, but only 16 digits after the dot is output.

Someone please help me..

Thanks

-Pimpy-

[MNovy]

Precision is 15-16 digits:

http://msdn.microsoft.com/en-gb/libr...k9(VS.80).aspx

[Hobson]

That is how Double type works: it has only 16 significant digits of precision. You need to use some arbitrary precision decimal class, like System.Decimal or something similar.

[JonnyPoet]

The best precision you can get using standard Types is using decimal values
There you will get

decimal val = 100.123456789123456789123456789123456789M;
Console.WriteLine(" {0}", val);
// printout shows 100.12345678912345678912345679

Rounded at the 26 th digit. But get it the total amount of digits is 29 here so if you have 1.123456789123456789123456789123456789M; then the answer will be 1.1234567891234567891234567891 All together always 29 digits. Simple try it.

BTW Why do you need such an amount of precision ?

[Pimpya]

Thank you for appeasing my anger. I have been trying it out all night only to fail again...and...again. I'd like to add in an M also at the tail of my Doubles but I feel like going without M because I have to read data from a file.
I can only say Thanks but truly am unable to pay back anything if you could help me solve the problem.

I need precision because I'd like to show the users the precision as many as they want, not just 29..

Sincerely
-Pimpy-

[JonnyPoet]

Thank you for appeasing my anger. I have been trying it out all night only to fail again...and...again. I'd like to add in an M also at the tail of my Doubles but I feel like going without M because I have to read data from a file.
I can only say Thanks but truly am unable to pay back anything if you could help me solve the problem.

I need precision because I'd like to show the users the precision as many as they want, not just 29..

Sincerely
-Pimpy-

Hmm yea, maybe interesting in some math or physic applications but as you see this is standard.
I have once long ago written code that was able to get a number with up to 63 digits as a string ( from a Textbox ) changed the value to binary also contained in an strings bit pattern and then written basic calculations for this like plus ( add), minus (substract), multiply and devide. But this was done in old VB 6.0 and was a lot of work. But Basically you can do this for your own. Transform the value digit by digit into bits (but you need to have a look on the real decimal value of it store them into a int64 ( or use a bit array ) and then figure out the mathematical operations for it, which are easy when doing it binary
in the end the result you will have to retransfer into a string showing the result. But you have to really have a look what you are doing when multiplying two numbers both maybe 63 digits long. Where is the end in your precision. ? Nothing in the world is endless my dear. So if there is no real need forget this brilliant idea. In most normal cases 29 digits are more, much more then enough.