In article <w_U%8.613$0m5.6883@eagle.america.net>, "Travis"
<oly_chierf_17@hotmail.com> wrote:

>not sure if this is the right newsgroup to send this to
>
>does the standard library have any algorithms for parsing double for strings
>(c-style or c++ style)?  i am trying to write my own, but sometimes it
>doesn't return the right number.
>
>also does anyone know if there good c++ API that i can download?

Convert the string to a stream using std::(i)stringstream in <sstream>,
and use the usual stream reading features. (Or strictly speaking, this
header will contain a std__basic_(i)stringstream and via a typedef in a
header iosfwd provide std::(i)stringstream.)

For simple parsing like this, you can hang out in the comp.c++ newsgroups.

For more complicated parsing, up to writing ones own language, one can use
lexer/parser generators like Flex/Bison <http://www.gnu.org>, which
currently are updated to support the current C++ standard. On this level,
the newsgroup comp.compilers and its FAQ published there regularly, is
useful.

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not sure if this is the right newsgroup to send this to

does the standard library have any algorithms for parsing double for strings
(c-style or c++ style)?  i am trying to write my own, but sometimes it
doesn't return the right number.

also does anyone know if there good c++ API that i can download?


======================================= MODERATOR'S COMMENT:

I'm approving this because you're asking about the contents
of the Standard Library.  If you want to ask about nonstandard
C++ APIs that you can download, you'd be better off with a
different newsgroup.

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Hi Travis,

if you want to see how it is done the simplest is probably to look for the sources of the strtod() function. Or alternatively you
could try to get a copy of P.J.Plauger book on the standard C library, which has the additional benefits of having comments.

Cheers

Renato

"Travis" <oly_chierf_17@hotmail.com> wrote in message news:w_U%8.613$0m5.6883@eagle.america.net...
not sure if this is the right newsgroup to send this to

does the standard library have any algorithms for parsing double for strings
(c-style or c++ style)?  i am trying to write my own, but sometimes it
doesn't return the right number.




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"Travis" <oly_chierf_17@hotmail.com> wrote in message
news:w_U%8.613$0m5.6883@eagle.america.net...
> not sure if this is the right newsgroup to send this to
>
> does the standard library have any algorithms for parsing double for
strings
> (c-style or c++ style)?  i am trying to write my own, but sometimes it
> doesn't return the right number.

std::istringstream i(inputString);
double d;
i >> d;

Ken


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