Converting double to float

This problem only occurs when dealing with large numbers or numbers with a lot of fraction digits.
Here is an example:
double d = 7.1E9;
float f1 = (float)d;
float f2 = new Float(d).floatValue();
System.out.println( d + " " + f1 + " " + f2);
The result is:
7.1E9 7.1000003E9 7.1000003E9
I tried other ways of converting to float (using DecimalFormat) but unfortunately nothing works. The resulting float is not the same as the original double.
Any ideas?
Thanks.
Igor.

float is only 32 bit while double is 64 bit, so you can easily get differences like that.
Is it a problem? If you results gets inaccurate you should stay with double or use BigDecimal if you really care about the precision. If it's because you want to round the result of before you display it, you can use DecimalFormat.

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