R help - Dec 2009 - as.numeric is truncating!

I am trying to convert a string to  a double using "as.numeric"
However, R is truncating the results!

Options(digits) is set to 7.

Can anyone shed some light on this?
Thanks!

> b[1]
[1] "116.28125"
> summary(b[1])
   Length     Class      Mode 
        1 character character 
> c <- as.numeric(b[1])
> c
[1] 116.2812



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ticspd wrote:
> 
> I am trying to convert a string to  a double using "as.numeric"
> However, R is truncating the results!
> 
> Options(digits) is set to 7.
> 
> Can anyone shed some light on this?
> Thanks!
> > b[1]
> [1] "116.28125"
>> summary(b[1])
>    Length     Class      Mode 
>         1 character character 
> 
>> c <- as.numeric(b[1])
>> c
> [1] 116.2812
> 
Try the following:

?round

(Note: and look in the Details section).

as.numeric("116.28135")

Set options(digits=8) and do the print again.

R is not truncating; it is following certain rounding rules on printing the
number given the required
numbers of digits to show.

Berend
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ah perfect .. digits = 8 is actually 8 digits TOTAL, not 8 digits after the
decimal point!
setting the default to 15 works for me

thank you!



Berend Hasselman wrote:
> 
> 
> 
> 
> ticspd wrote:
>> 
>> I am trying to convert a string to  a double using
"as.numeric"
>> However, R is truncating the results!
>> 
>> Options(digits) is set to 7.
>> 
>> Can anyone shed some light on this?
>> Thanks!
>> > b[1]
>> [1] "116.28125"
>>> summary(b[1])
>>    Length     Class      Mode 
>>         1 character character 
>> 
>>> c <- as.numeric(b[1])
>>> c
>> [1] 116.2812
>> 
> 
> Try the following:
> 
> ?round
> 
> (Note: and look in the Details section).
> 
> as.numeric("116.28135")
> 
> Set options(digits=8) and do the print again.
> 
> R is not truncating; it is following certain rounding rules on printing
> the number given the required
> numbers of digits to show.
> 
> Berend
> 
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ticspd wrote:
> I am trying to convert a string to  a double using "as.numeric"
> However, R is truncating the results!
No it isn't! As someone phrased it recently, there's a difference 
between an object and the display of an object. "Ceci n'est pas une
pipe".
> Options(digits) is set to 7.
So numbers are _printed_ to 7-digit accuracy, yes. (And 116.28125 has 8 
digits.)
> Can anyone shed some light on this?
Subtract 116, and enlightenment should follow.

> Thanks!
> 
> 
>> b[1]
> [1] "116.28125"
> 
>> summary(b[1])
>    Length     Class      Mode 
>         1 character character 
> 
>> c <- as.numeric(b[1])
>> c
> [1] 116.2812
> 
> 
> 

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