i have input which is : 602.8235291 but i noticed that when i do :
float x1 = 602.8235291;
printf("%f", x1);
The output is : 602.823547 as you see it is different in the precision . how can i maintain the same value in x1 ?
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4Use a `double` instead. – alk Jul 21 '16 at 13:59
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@alk Sir, how is that going to affect the default precision of six? – Sourav Ghosh Jul 21 '16 at 14:02
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Adding on to Alk, a `float` only has 23 bits of mantissa for ~7 decimal digits of precision – Kevin L Jul 21 '16 at 14:02
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@alk It will *reduce* the effect, but won't eliminate it.. – Eugene Sh. Jul 21 '16 at 14:02
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... and put an F at the end of your constant litteral : 602.8235291F – clarasoft-it Jul 21 '16 at 14:02
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Short answer: You can't with the standard floating-point representation. – Eugene Sh. Jul 21 '16 at 14:03
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@SouravGhosh: The question is "*How can i maintain the same value **in** `x1`*" ;-) – alk Jul 21 '16 at 14:03
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2@clarasoft-it: Aren't floating point literals `double` by default? – alk Jul 21 '16 at 14:07
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@alk yes, you are right. So adding the F will not work, my mistake – clarasoft-it Jul 21 '16 at 14:15
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2There are infinite number of of numbers. There are typically about 2**32 different exactly representable `float` values. `602.823_5291` is not one of them - so code cannot maintain that _same exact_ value. `602.823_54736328125` is the closest one. `602.823_48632812` is the next closest one. Expect `float` to maintain `FLT_DIG` (e.g. 6) significant digits as in `602.823`. – chux - Reinstate Monica Jul 21 '16 at 15:03