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Float and Double in Perl

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# 1  
Old 10-28-2005
Float and Double in Perl
HI!

What is the notation which correspond to C's
Code:
double

and
Code:
float

in Perl??

Please tell me.
Thanks.

Well what I want to do is, for example, calculating
Code:
sqrt(2)

in two way: float and double.
# 2  
Old 10-29-2005
No, Perl stores/processes everything internally as doubles, so there is no distinction between float and double. You can control how many decimal places to display, for instance, with printf()/sprintf(). For instance, running the followings on my Windows system give these:

Code:
D:\Documents and Settings\bernardchan>perl -e "printf('%f', 13/7)"
1.857143
D:\Documents and Settings\bernardchan>perl -e "printf('%0.10f', 13/7)"
1.8571428571

# 3  
Old 10-31-2005
Thank you for your help.
Well I will give it up, and do it with C.
Thanks!
# 4  
Old 03-14-2008
i have problems working with float

id try with

printf('%0.10f',3/2);

and it prints "1.0000000000" instead of "1,5000.."

do i have to use some math perl module??

thanks
# 5  
Old 03-14-2008
Well, on both my Windows and Linux systems "1.5000000000" was printed.

It is possible that the std C library used to compile the perl interpreter may influence that behaviour, but I am not exactly sure.
# 6  
Old 03-14-2008
perl is supposed to interpret numbers as doubles, and you have to force a number to becomes an integer with the int function.

Out of curioisity what does this give?
Code:
printf("%0.10f",3/2);

Changes the ' to " around the format specification...
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