adding numbers don't add up..

[Dave Chamberlin]

I have a small C program that adds .01 to a number X times.
If the number is 1000, the result is 10.00, for 10000 the result is 100.00 but for higher numbers, the result is not correct (x=100000 gives 1000.67, x=1000000 gives 9865.22). What gives?

[Sachin Patel]

Hi Dave,
try double or long I am not sure. It is been long time.

long flot x;

Sachin

[Kenneth Platz]

Dave,

What datatype are you using for your additions? If you're currently using a "float", then you may want to try using a "double" or "long double", because those have greater precision.

I hope this helps.

[Rodney Hills]

Due to the way floating point numbers are represented, the concept of precision is taken with a grain of salt.

If you wish to calculate to exactly 2 decimal places, then scale an integer number (ie instead of 1.23 of "real" type, use 123 in integer). Thus in calculations your results will be precise. Convert to "real" only for printing.

[Andreas Voss · Accepted solution]

Hi,

setting

double f=0.0;

is sufficient.

Regards