floating point error

[sandeepdhankar10]

hi experts,

i am facing trouble with float data types.

when i try to parse a value to float it gives me diffrent value.

e.g float test = (float.Parse("149.128156"));

gives me test=149.128159

i am very fed up of this.. pls help me out ...

i want the exact values of what i gave as input.

thanks in advance

[tlhintoq]

More about floats than you would want to know:
http://docs.sun.com/source/806-3568/ncg_goldberg.html

But I do notice that a double works fine for your example:

            float Test = float.Parse("149.128156");// Breakpoint here and walk through looking at Locals values
            float Bob = Test;// Yep, Bob is wrong here
            MessageBox.Show("Parse",Test.ToString());
            double Yogi = double.Parse("149.128156");
            double booboo = Yogi;// But Yogi is right here
            MessageBox.Show("Double", Yogi.ToString());
 

[sandeepdhankar10]

thanks tlhintoq fro your response.

i know that i can get my values by using double..

but i have a problem in which i must have to use float.

so pls give me some suggestion by which i can get perfect values in float

[tlhintoq]

Since you know parsing to a double gets you the right value, I would experiment from that. Parse to a double, then seat a float equal to the double; and so on. See if some combination of those get you a usable float as the final step.

[sandeepdhankar10]

i do not get you .. can you pls little more specific with a small example/..

thanks in advance

[tlhintoq]

double Yogi = double.Parse("149.128156");
float bob = Yogi
// the Double does the parsing accurately
// then gives it to a float for you to use elsewhere per your need to use a float.
 

[sandeepdhankar10]

thanks for your response but...
its not working b/c there is no implicit conversion from double to float .in c#
we have to write as follows
float bob =(float) Yogi;

then it again gives me 149.128159

so still i have same problem.