Help with rounding a number

This is a discussion on Help with rounding a number within the C Programming forums, part of the General Programming Boards category; Hi, I have a math project in which i need to round numbers correctly (ie. not just rounding up, but ...

  1. #1
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    Help with rounding a number

    Hi, I have a math project in which i need to round numbers correctly (ie. not just rounding up, but proper rounding, so if it was 4.4 it would become 4, and if it was 4.5 it would be 5). Now its easy enough to convert a float to an int, but then it allways rounds up, is it possible to somehow round it correctly?

    Thanks, Nick

  2. #2
    ATH0 quzah's Avatar
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    How many decimal places do you want to round? I won't give you any code, because that would simply give you the answer to your homework. We don't do that. Just think about the problem:
    1) Read the decimal place.
    2) Round up if higher than N, otherwise round down.

    It's really not that hard.

    Quzah.
    Hope is the first step on the road to disappointment.

  3. #3
    C Programmer Stack Overflow's Avatar
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    I agree,

    It's not hard. It can be done in one line of code, but I'm here on quzah's side because I want "to make them think" - by Quzah

    Yeah, I like that phrase in your signature. Now maybe to help with a few hints you can use the math header <math.h> possibly using abs, floor, ceil or even seperately modf, etc...

    Anyway, here is a link to all the codes given in the header file math.h


    Hope this helps,
    - Stack Overflow
    Segmentation Fault: I am an error in which a running program attempts to access memory not allocated to it and core dumps with a segmentation violation error. This is often caused by improper usage of pointers, attempts to access a non-existent or read-only physical memory address, re-use of memory if freed within the same scope, de-referencing a null pointer, or (in C) inadvertently using a non-pointer variable as a pointer.

  4. #4
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    there is one function in math.h that exactly answers ur requirements. it is called "round" itself. i am not sure but as far as i know it is a standard function. why dont u just check it out
    even a fish would not have been in danger had it kept its mouth shut.

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