How to verify if a value stored in a double is an integer value?
Hi,
I am writing matrix to files. The values in the cels of matrix are double or int.
So I do use fprinf("..."%.4f", value)
for write all values with 4 decimal places.
But sometimes all values in the matrix are int values, in this case I prefer to wrie them as %d, whithout decimal places.
It need to mention that all values are stored in a variable of type double.
How can I check if a particular value require decimal places or, in other words, how to check if that value can be stored in a int?
I am writing matrix to files. The values in the cels of matrix are double or int.
So I do use fprinf("..."%.4f", value)
for write all values with 4 decimal places.
But sometimes all values in the matrix are int values, in this case I prefer to wrie them as %d, whithout decimal places.
It need to mention that all values are stored in a variable of type double.
How can I check if a particular value require decimal places or, in other words, how to check if that value can be stored in a int?
You can use modf :
http://www.cplusplus.com/reference/clibrary/cmath/modf/
and check if fractional part equals to 0 and if yes that would mean that your number could be stored as an int
http://www.cplusplus.com/reference/clibrary/cmath/modf/
and check if fractional part equals to 0 and if yes that would mean that your number could be stored as an int
closed account (1yR4jE8b)
kbw is right, std::iostream exists so you shouldn't have to deal with cases like this. fprintf() is old C language and is only in C++ for backwards compatibility.
I proposed modf since he was using plain C. Of course C++ is more flexible. You will be amazed with how much C is out there though :)
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