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Re: Initializing sum to zero wouldn't compile

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Alla _ <modelling.data@gmail.com> writes:

>> >    for ( i = 0; i < 3; i++)
>> >    {
>> >        scanf ("%f", &element);
>> >        
>> >            is_float = 1;
>> >            n = (int) element; /*casting allows to check if 
>> >               the value entered by the user is a float or 
>> >               an integer; when I turn element into integer, 
>> >               then (int) element - element tests the entered value*/
>> 
>> The cast does no such thing.  What happens differently if you delete
>> the cast?
> Well, as I initialized element as a float, I assumed
> that even if the user enters an integer, the compiler 
> will take it as a float X.XX..

You mean "declared" not "initialized".  Yes, it will always be treated
as a double (one of the floating point types).

> Therefore, when I cast int to the entered variable element 
> and initialize the result to variable n,

You've missed Barry's point: "What happens differently if you delete the
cast?".  The answer is nothing.  The code is identical with and without
the cast.  Assigning a double to an int converts the double by throwing
away the fractional part.  The cast does exactly the same thing.

> then when I deduct 
> from integer n the float variable element, the result should 
> be a number with decimal points (then it is a float),
> or without decimal points (then it is an integer, i.e.
> n - element == 0).
>
>> 
>> >        if (n - element == 0 || element == 0 ) 
>          /*element == 0 allows to skip zero values*/
>> 
>> If element is 0, the second comparison will never even be evaluated.
>> Therefore it is completely useless.
>
> Now I see it. Thank you. 
>> 
>> WHY is a floating point number with a fractional value of 0 considered
>> invalid? 
>
> Mathematically and scientifically it is a float number, but given my
> lack of knowledge, I couldn't yet find the way to test both for
> integers and for floats with zeros after decimal points.

This keeps missing the point.  Why do you care?  The user enters a
number.  You add it to the sum.  What is there to test?

I am pretty sure that this reflects some misunderstanding about types
and input, but I can't put my finger on it so I can't correct it.

<snip>
-- 
Ben.

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Initializing sum to zero wouldn't compile Alla _ <modelling.data@gmail.com> - 2015-08-21 04:39 -0700
  Re: Initializing sum to zero wouldn't compile James Kuyper <jameskuyper@verizon.net> - 2015-08-21 07:54 -0400
    Re: Initializing sum to zero wouldn't compile Alla _ <modelling.data@gmail.com> - 2015-08-21 05:27 -0700
      Re: Initializing sum to zero wouldn't compile Keith Thompson <kst-u@mib.org> - 2015-08-21 10:28 -0700
        Re: Initializing sum to zero wouldn't compile Alla _ <modelling.data@gmail.com> - 2015-08-21 11:15 -0700
    Re: Initializing sum to zero wouldn't compile Alla _ <modelling.data@gmail.com> - 2015-08-21 05:30 -0700
  Re: Initializing sum to zero wouldn't compile Ike Naar <ike@iceland.freeshell.org> - 2015-08-21 12:40 +0000
    Re: Initializing sum to zero wouldn't compile Alla _ <modelling.data@gmail.com> - 2015-08-21 11:16 -0700
  Re: Initializing sum to zero wouldn't compile Siri Cruz <chine.bleu@yahoo.com> - 2015-08-21 07:41 -0700
    Re: Initializing sum to zero wouldn't compile Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2015-08-21 10:56 -0400
    Re: Initializing sum to zero wouldn't compile Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2015-08-21 09:28 -0600
  Re: Initializing sum to zero wouldn't compile Barry Schwarz <schwarzb@dqel.com> - 2015-08-21 10:02 -0700
    Re: Initializing sum to zero wouldn't compile Alla _ <modelling.data@gmail.com> - 2015-08-21 11:21 -0700
      Re: Initializing sum to zero wouldn't compile Barry Schwarz <schwarzb@dqel.com> - 2015-08-21 22:27 -0700
        Re: Initializing sum to zero wouldn't compile Alla _ <modelling.data@gmail.com> - 2015-08-22 02:25 -0700
  Re: Initializing sum to zero wouldn't compile Alla _ <modelling.data@gmail.com> - 2015-08-22 03:50 -0700
    Re: Initializing sum to zero wouldn't compile Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-08-22 13:18 +0100
      Re: Initializing sum to zero wouldn't compile Alla _ <modelling.data@gmail.com> - 2015-08-22 11:21 -0700
        Re: Initializing sum to zero wouldn't compile Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-08-22 21:55 +0100
          Re: Initializing sum to zero wouldn't compile Alla _ <modelling.data@gmail.com> - 2015-08-26 01:36 -0700
            Re: Initializing sum to zero wouldn't compile Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-08-26 11:24 +0100
        Re: Initializing sum to zero wouldn't compile Barry Schwarz <schwarzb@dqel.com> - 2015-08-22 17:17 -0700
          Re: Initializing sum to zero wouldn't compile Alla _ <modelling.data@gmail.com> - 2015-08-26 01:26 -0700
            Re: Initializing sum to zero wouldn't compile Barry Schwarz <schwarzb@dqel.com> - 2015-08-26 02:27 -0700
              Re: Initializing sum to zero wouldn't compile Alla _ <modelling.data@gmail.com> - 2015-08-26 04:21 -0700
                Re: Initializing sum to zero wouldn't compile Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-08-26 12:37 +0100
                Re: Initializing sum to zero wouldn't compile Richard Heathfield <rjh@cpax.org.uk> - 2015-08-26 13:06 +0100
                Re: Initializing sum to zero wouldn't compile Bartc <bc@freeuk.com> - 2015-08-26 13:43 +0100
                Re: Initializing sum to zero wouldn't compile Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-08-26 14:03 +0100
                Re: Initializing sum to zero wouldn't compile Richard Heathfield <rjh@cpax.org.uk> - 2015-08-26 14:06 +0100
                Re: Initializing sum to zero wouldn't compile Tim Rentsch <txr@alumni.caltech.edu> - 2015-09-06 15:14 -0700
                Re: Initializing sum to zero wouldn't compile Keith Thompson <kst-u@mib.org> - 2015-08-26 11:38 -0700
                Re: Initializing sum to zero wouldn't compile Keith Thompson <kst-u@mib.org> - 2015-08-26 11:44 -0700
    Re: Initializing sum to zero wouldn't compile Barry Schwarz <schwarzb@dqel.com> - 2015-08-22 10:49 -0700
      Re: Initializing sum to zero wouldn't compile Alla _ <modelling.data@gmail.com> - 2015-08-22 11:16 -0700
  Re: Initializing sum to zero wouldn't compile Alla _ <modelling.data@gmail.com> - 2015-08-29 07:19 -0700
    Re: Initializing sum to zero wouldn't compile Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-08-29 15:35 +0100
      Re: Initializing sum to zero wouldn't compile Alla _ <modelling.data@gmail.com> - 2015-08-30 02:11 -0700
        Re: Initializing sum to zero wouldn't compile Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-08-30 12:28 +0100
          Re: Initializing sum to zero wouldn't compile Keith Thompson <kst-u@mib.org> - 2015-08-30 15:02 -0700
            Re: Initializing sum to zero wouldn't compile Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-08-30 22:36 +0100
              Re: Initializing sum to zero wouldn't compile Keith Thompson <kst-u@mib.org> - 2015-08-30 16:10 -0700
                Re: Initializing sum to zero wouldn't compile Bartc <bc@freeuk.com> - 2015-08-31 00:14 +0100
                Re: Initializing sum to zero wouldn't compile Keith Thompson <kst-u@mib.org> - 2015-08-30 19:56 -0700
    Re: Initializing sum to zero wouldn't compile Bartc <bc@freeuk.com> - 2015-08-29 16:57 +0100
      Re: Initializing sum to zero wouldn't compile Bartc <bc@freeuk.com> - 2015-08-29 17:37 +0100
      Re: Initializing sum to zero wouldn't compile Alla _ <modelling.data@gmail.com> - 2015-08-30 02:14 -0700

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