Solved

Question! Converting String to a double or Integer where the value is rounded up or down?

Posted on 2006-07-24
3
216 Views
Last Modified: 2010-04-01
Hi guys,

My question is about how, when received a string& one can take that string and convert it to double,
alternatively I want the string to be converted into an integer rounded up or down ie value in from string is 1.560008 then the int = 2 etc.

Here's how I failed to convert the string& to double:

void getValue(string& theValue) {
      double d;
      char l [256];
      l = theValue;
      d = atof(theValue);
      cout << d << endl;
      cout << flush;
}

any inputs are welcomed

All the best
Idar
0
Comment
Question by:Idarhillgaar
  • 2
3 Comments
 
LVL 7

Accepted Solution

by:
nafis_devlpr earned 250 total points
ID: 17166576
you can do it this way

 d = atof(theValue.c_str());

or

sscanf(theValue.c_str(), "%lf", &d);

for the second question, do the above then do this

int i= (int)(d+0.5);

hope this helps

Nafis
0
 
LVL 7

Expert Comment

by:nafis_devlpr
ID: 17166592
>> int i= (int)(d+0.5);

this will actually round the values, for example :

if 1.5 it will be 2
if 1.4 it will be 1

you can also use the ceil or floor to round-up or round-down the values, for exmple

if  1.5
then ceil(1.5) will give 2.0
and floor(1.5) will give 1.0


Nafis
0
 

Author Comment

by:Idarhillgaar
ID: 17166719
Fabulous answers - Have a good summer!

Cheers
Idar
0

Featured Post

Networking for the Cloud Era

Join Microsoft and Riverbed for a discussion and demonstration of enhancements to SteelConnect:
-One-click orchestration and cloud connectivity in Azure environments
-Tight integration of SD-WAN and WAN optimization capabilities
-Scalability and resiliency equal to a data center

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Templates For Beginners Or How To Encourage The Compiler To Work For You Introduction This tutorial is targeted at the reader who is, perhaps, familiar with the basics of C++ but would prefer a little slower introduction to the more ad…
  Included as part of the C++ Standard Template Library (STL) is a collection of generic containers. Each of these containers serves a different purpose and has different pros and cons. It is often difficult to decide which container to use and …
The goal of the video will be to teach the user the difference and consequence of passing data by value vs passing data by reference in C++. An example of passing data by value as well as an example of passing data by reference will be be given. Bot…
The viewer will learn how to pass data into a function in C++. This is one step further in using functions. Instead of only printing text onto the console, the function will be able to perform calculations with argumentents given by the user.

765 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question