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float

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  float ramtin <tom.t.2090@gmail.com> - 2011-10-17 12:40 -0700
    Re: float Dombo <dombo@disposable.invalid> - 2011-10-17 21:47 +0200
    Re: float Thomas Boell <tboell@domain.invalid> - 2011-10-17 21:50 +0200
      Re: float Sjouke Burry <S@P.NL> - 2011-10-26 23:13 +0000
    Re: float Saeed Amrollahi <amrollahi.saeed@gmail.com> - 2011-10-17 13:05 -0700
      Re: float Ian Collins <ian-news@hotmail.com> - 2011-10-18 09:23 +1300
        Re: float Leigh Johnston <leigh@i42.co.uk> - 2011-10-17 21:25 +0100
          Re: float Leigh Johnston <leigh@i42.co.uk> - 2011-10-17 21:31 +0100
            Re: float Leigh Johnston <leigh@i42.co.uk> - 2011-10-17 21:33 +0100
            Re: float Ian Collins <ian-news@hotmail.com> - 2011-10-18 09:35 +1300
              Re: float ramtin <tom.t.2090@gmail.com> - 2011-10-17 13:49 -0700
    Re: float Ian Collins <ian-news@hotmail.com> - 2011-10-18 09:19 +1300
      Re: float "Paul" <pchrist<nospam>or@yahoo.co.uk> - 2011-10-18 00:55 +0100
        Re: float SG <s.gesemann@gmail.com> - 2011-10-18 05:34 -0700
          Re: float Christopher <cpisz@austin.rr.com> - 2011-10-27 14:29 -0700
            Re: float Dombo <dombo@disposable.invalid> - 2011-10-28 18:14 +0200
    Re: float 88888 Dihedral <dihedral88888@googlemail.com> - 2011-10-28 21:06 -0700
      Re: float red floyd <no.spam.here@its.invalid> - 2011-10-28 22:14 -0700
        Re: float 88888 Dihedral <dihedral88888@googlemail.com> - 2011-10-28 23:27 -0700
          Re: float red floyd <no.spam.here@its.invalid> - 2011-10-29 08:24 -0700
            Re: float ptyxs <kerloch@gmail.com> - 2011-10-30 01:40 -0700
              Re: float Ian Collins <ian-news@hotmail.com> - 2011-10-30 22:27 +1300

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#10936 — float

hi all ,

#include "stdafx.h"
#include <stdio.h>
using namespace System;

int main(array<System::String ^> ^args)
{
	float d = 4 / 3 ;
	printf("%f",d);
    return 0;
}

when you run this ,it will be 1 in d ,but it should be 1.3333 in it !!!

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#10938

Op 17-Oct-11 21:40, ramtin schreef:
> hi all ,
>
> #include "stdafx.h"
> #include<stdio.h>
> using namespace System;
>
> int main(array<System::String ^>  ^args)
> {
> 	float d = 4 / 3 ;
> 	printf("%f",d);
>      return 0;
> }
>
> when you run this ,it will be 1 in d ,but it should be 1.3333 in it !!!

That is because 4 and 3 are integers, so the result of the division will 
be an integer as well, after that the integer result is converted to a 
float. If you use 4.0/3.0 you should get something close to 1.3333.

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#10939

On Mon, 17 Oct 2011 12:40:40 -0700 (PDT)
ramtin <tom.t.2090@gmail.com> wrote:

> hi all ,
> 
> #include "stdafx.h"
> #include <stdio.h>
> using namespace System;
> 
> int main(array<System::String ^> ^args)
> {
> 	float d = 4 / 3 ;
> 	printf("%f",d);
>     return 0;
> }
> 
> when you run this ,it will be 1 in d ,but it should be 1.3333 in it !!!

What language is it?

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#11109

Thomas Boell <tboell@domain.invalid> wrote in 
news:20111017215005.66a8d93d@arcadia:

> On Mon, 17 Oct 2011 12:40:40 -0700 (PDT)
> ramtin <tom.t.2090@gmail.com> wrote:
> 
>> hi all ,
>> 
>> #include "stdafx.h"
>> #include <stdio.h>
>> using namespace System;
>> 
>> int main(array<System::String ^> ^args)
>> {
>>      float d = 4 / 3 ;
>>      printf("%f",d);
>>     return 0;
>> }
>> 
>> when you run this ,it will be 1 in d ,but it should be 1.3333 in it 
cut

(int(4/(int)3  equals 1.
so whats new today??

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#10940

On Oct 17, 10:40 pm, ramtin <tom.t.2...@gmail.com> wrote:
> hi all ,
>
> #include "stdafx.h"
> #include <stdio.h>
> using namespace System;
>
> int main(array<System::String ^> ^args)
> {
>         float d = 4 / 3 ;
>         printf("%f",d);
>     return 0;
>
> }
>
> when you run this ,it will be 1 in d ,but it should be 1.3333 in it !!!

Hi Ramtin
Besides what Dombo wrote you can use static_cast:
    float d = static_cast<float>(4)/3;

Regards,
   -- Saeed Amrollahi

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#10942

On 10/18/11 09:05 AM, Saeed Amrollahi wrote:
> On Oct 17, 10:40 pm, ramtin<tom.t.2...@gmail.com>  wrote:
>> hi all ,
>>
>> #include "stdafx.h"
>> #include<stdio.h>
>> using namespace System;
>>
>> int main(array<System::String ^>  ^args)
>> {
>>          float d = 4 / 3 ;
>>          printf("%f",d);
>>      return 0;
>>
>> }
>>
>> when you run this ,it will be 1 in d ,but it should be 1.3333 in it !!!
>
> Hi Ramtin
> Besides what Dombo wrote you can use static_cast:
>      float d = static_cast<float>(4)/3;

If the OP were using C++, wouldn't it be easier just to write

float d = float(4) / 3;

?

Either way, the rules of whatever language the OP is using may be different.

-- 
Ian Collins

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#10943

On 17/10/2011 21:23, Ian Collins wrote:
> On 10/18/11 09:05 AM, Saeed Amrollahi wrote:
>> On Oct 17, 10:40 pm, ramtin<tom.t.2...@gmail.com> wrote:
>>> hi all ,
>>>
>>> #include "stdafx.h"
>>> #include<stdio.h>
>>> using namespace System;
>>>
>>> int main(array<System::String ^> ^args)
>>> {
>>> float d = 4 / 3 ;
>>> printf("%f",d);
>>> return 0;
>>>
>>> }
>>>
>>> when you run this ,it will be 1 in d ,but it should be 1.3333 in it !!!
>>
>> Hi Ramtin
>> Besides what Dombo wrote you can use static_cast:
>> float d = static_cast<float>(4)/3;
>
> If the OP were using C++, wouldn't it be easier just to write
>
> float d = float(4) / 3;

No it would be easier to just write

float d = 4.0f / 3.0f;

/Leigh

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#10944

On 17/10/2011 21:25, Leigh Johnston wrote:
> On 17/10/2011 21:23, Ian Collins wrote:
>> On 10/18/11 09:05 AM, Saeed Amrollahi wrote:
>>> On Oct 17, 10:40 pm, ramtin<tom.t.2...@gmail.com> wrote:
>>>> hi all ,
>>>>
>>>> #include "stdafx.h"
>>>> #include<stdio.h>
>>>> using namespace System;
>>>>
>>>> int main(array<System::String ^> ^args)
>>>> {
>>>> float d = 4 / 3 ;
>>>> printf("%f",d);
>>>> return 0;
>>>>
>>>> }
>>>>
>>>> when you run this ,it will be 1 in d ,but it should be 1.3333 in it !!!
>>>
>>> Hi Ramtin
>>> Besides what Dombo wrote you can use static_cast:
>>> float d = static_cast<float>(4)/3;
>>
>> If the OP were using C++, wouldn't it be easier just to write
>>
>> float d = float(4) / 3;
>
> No it would be easier to just write
>
> float d = 4.0f / 3.0f;

Or even:

float d = 4.0 / 3.0;

as the compiler will probably optimize the division into a constant 
assignment.

/Leigh

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#10945

On 17/10/2011 21:31, Leigh Johnston wrote:
> On 17/10/2011 21:25, Leigh Johnston wrote:
>> On 17/10/2011 21:23, Ian Collins wrote:
>>> On 10/18/11 09:05 AM, Saeed Amrollahi wrote:
>>>> On Oct 17, 10:40 pm, ramtin<tom.t.2...@gmail.com> wrote:
>>>>> hi all ,
>>>>>
>>>>> #include "stdafx.h"
>>>>> #include<stdio.h>
>>>>> using namespace System;
>>>>>
>>>>> int main(array<System::String ^> ^args)
>>>>> {
>>>>> float d = 4 / 3 ;
>>>>> printf("%f",d);
>>>>> return 0;
>>>>>
>>>>> }
>>>>>
>>>>> when you run this ,it will be 1 in d ,but it should be 1.3333 in it
>>>>> !!!
>>>>
>>>> Hi Ramtin
>>>> Besides what Dombo wrote you can use static_cast:
>>>> float d = static_cast<float>(4)/3;
>>>
>>> If the OP were using C++, wouldn't it be easier just to write
>>>
>>> float d = float(4) / 3;
>>
>> No it would be easier to just write
>>
>> float d = 4.0f / 3.0f;
>
> Or even:
>
> float d = 4.0 / 3.0;
>
> as the compiler will probably optimize the division into a constant
> assignment.
>

Actually no as that will probably result in a truncation warning so 
yeah, 4.0f / 3.0f is the way to go.

/Leigh

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#10946

On 10/18/11 09:31 AM, Leigh Johnston wrote:
> On 17/10/2011 21:25, Leigh Johnston wrote:
>> On 17/10/2011 21:23, Ian Collins wrote:
>>> On 10/18/11 09:05 AM, Saeed Amrollahi wrote:
>>>> On Oct 17, 10:40 pm, ramtin<tom.t.2...@gmail.com>  wrote:
>>>>> hi all ,
>>>>>
>>>>> #include "stdafx.h"
>>>>> #include<stdio.h>
>>>>> using namespace System;
>>>>>
>>>>> int main(array<System::String ^>  ^args)
>>>>> {
>>>>> float d = 4 / 3 ;
>>>>> printf("%f",d);
>>>>> return 0;
>>>>>
>>>>> }
>>>>>
>>>>> when you run this ,it will be 1 in d ,but it should be 1.3333 in it !!!
>>>>
>>>> Hi Ramtin
>>>> Besides what Dombo wrote you can use static_cast:
>>>> float d = static_cast<float>(4)/3;
>>>
>>> If the OP were using C++, wouldn't it be easier just to write
>>>
>>> float d = float(4) / 3;
>>
>> No it would be easier to just write
>>
>> float d = 4.0f / 3.0f;
>
> Or even:
>
> float d = 4.0 / 3.0;
>
> as the compiler will probably optimize the division into a constant
> assignment.

That was already posted (the "what Dombo wrote" referenced above).

My point was there is no need to use static_cast, a temporary will do. 
If the '4' was an integer variable for example.

-- 
Ian Collins

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#10948

On Oct 17, 1:35 pm, Ian Collins <ian-n...@hotmail.com> wrote:
> On 10/18/11 09:31 AM, Leigh Johnston wrote:
>
>
>
>
>
>
>
>
>
> > On 17/10/2011 21:25, Leigh Johnston wrote:
> >> On 17/10/2011 21:23, Ian Collins wrote:
> >>> On 10/18/11 09:05 AM, Saeed Amrollahi wrote:
> >>>> On Oct 17, 10:40 pm, ramtin<tom.t.2...@gmail.com>  wrote:
> >>>>> hi all ,
>
> >>>>> #include "stdafx.h"
> >>>>> #include<stdio.h>
> >>>>> using namespace System;
>
> >>>>> int main(array<System::String ^>  ^args)
> >>>>> {
> >>>>> float d = 4 / 3 ;
> >>>>> printf("%f",d);
> >>>>> return 0;
>
> >>>>> }
>
> >>>>> when you run this ,it will be 1 in d ,but it should be 1.3333 in it !!!
>
> >>>> Hi Ramtin
> >>>> Besides what Dombo wrote you can use static_cast:
> >>>> float d = static_cast<float>(4)/3;
>
> >>> If the OP were using C++, wouldn't it be easier just to write
>
> >>> float d = float(4) / 3;
>
> >> No it would be easier to just write
>
> >> float d = 4.0f / 3.0f;
>
> > Or even:
>
> > float d = 4.0 / 3.0;
>
> > as the compiler will probably optimize the division into a constant
> > assignment.
>
> That was already posted (the "what Dombo wrote" referenced above).
>
> My point was there is no need to use static_cast, a temporary will do.
> If the '4' was an integer variable for example.
>
> --
> Ian Collins

thanks of all . . .

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#10941

On 10/18/11 08:40 AM, ramtin wrote:
> hi all ,
>
> #include "stdafx.h"
> #include<stdio.h>
> using namespace System;
>
> int main(array<System::String ^>  ^args)

This looks like a language almost, but not entirely, unlike C++.

-- 
Ian Collins

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#10949

"Ian Collins" <ian-news@hotmail.com> wrote in message 
news:9g3gusFpouU2@mid.individual.net...
> On 10/18/11 08:40 AM, ramtin wrote:
>> hi all ,
>>
>> #include "stdafx.h"
>> #include<stdio.h>
>> using namespace System;
>>
>> int main(array<System::String ^>  ^args)
>
> This looks like a language almost, but not entirely, unlike C++.
>
That is the syntax use din MSVC++ when you create a windows form 
projec(C++), probably a .net thing. 



--- Posted via news://freenews.netfront.net/ - Complaints to news@netfront.net ---

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#10967

On 18 Okt., 01:55, Paul wrote:
> Ian Collins wrote in message
> > [...] ramtin wrote:
>
> >> int main(array<System::String ^>  ^args)
>
> > This looks like a language almost, but not entirely, unlike C++.
>
> That is the syntax use din MSVC++ when you create a windows form
> projec(C++), probably a .net thing.

I would guess that a large fraction of the competent regulars
(including Ian) already know exactly what it is: C++/CLI. And yes,
that's what you get if you ask Herb Sutter to make .NET easily
accessible from C++ by use of language extensions.

Off-topic: I makes me chuckle a bit to see almost the same syntax
being used for C++/CX where the CX language extensions are used to
deal with WinRT's ref-counting object system. I guess Microsoft lost a
bit of interest in .NET and C++/CLI since this seems to make the CLI
and CX extensions mutually exclusive. Btw, I can recommend Herb
Sutter's "modern C++" talk. It almost sounds like he's trying to
convert .NET developers. "Look, how easy it is to write modern and
safe C++ code!".

Cheers!
SG

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#11121

On Oct 18, 7:34 am, SG <s.gesem...@gmail.com> wrote:
> On 18 Okt., 01:55, Paul wrote:
>
> > Ian Collins wrote in message
> > > [...] ramtin wrote:
>
> > >> int main(array<System::String ^>  ^args)
>
> > > This looks like a language almost, but not entirely, unlike C++.
>
> > That is the syntax use din MSVC++ when you create a windows form
> > projec(C++), probably a .net thing.
>
> I would guess that a large fraction of the competent regulars
> (including Ian) already know exactly what it is: C++/CLI. And yes,
> that's what you get if you ask Herb Sutter to make .NET easily
> accessible from C++ by use of language extensions.
>
> Off-topic: I makes me chuckle a bit to see almost the same syntax
> being used for C++/CX where the CX language extensions are used to
> deal with WinRT's ref-counting object system. I guess Microsoft lost a
> bit of interest in .NET and C++/CLI since this seems to make the CLI
> and CX extensions mutually exclusive. Btw, I can recommend Herb
> Sutter's "modern C++" talk. It almost sounds like he's trying to
> convert .NET developers. "Look, how easy it is to write modern and
> safe C++ code!".
>
> Cheers!
> SG

I never really understood what advantage there would be in using C++/
CLI. If I want CLI, why wouldn't I just use C# instead? Maybe so I can
have pointers? OT anyway I suppose.

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#11134

Op 27-Oct-11 23:29, Christopher schreef:
> On Oct 18, 7:34 am, SG<s.gesem...@gmail.com>  wrote:
>> On 18 Okt., 01:55, Paul wrote:
>>
>>> Ian Collins wrote in message
>>>> [...] ramtin wrote:
>>
>>>>> int main(array<System::String ^>    ^args)
>>
>>>> This looks like a language almost, but not entirely, unlike C++.
>>
>>> That is the syntax use din MSVC++ when you create a windows form
>>> projec(C++), probably a .net thing.
>>
>> I would guess that a large fraction of the competent regulars
>> (including Ian) already know exactly what it is: C++/CLI. And yes,
>> that's what you get if you ask Herb Sutter to make .NET easily
>> accessible from C++ by use of language extensions.
>>
>> Off-topic: I makes me chuckle a bit to see almost the same syntax
>> being used for C++/CX where the CX language extensions are used to
>> deal with WinRT's ref-counting object system. I guess Microsoft lost a
>> bit of interest in .NET and C++/CLI since this seems to make the CLI
>> and CX extensions mutually exclusive. Btw, I can recommend Herb
>> Sutter's "modern C++" talk. It almost sounds like he's trying to
>> convert .NET developers. "Look, how easy it is to write modern and
>> safe C++ code!".
>>
>> Cheers!
>> SG
>
> I never really understood what advantage there would be in using C++/
> CLI. If I want CLI, why wouldn't I just use C# instead?

+1

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#11136

float d1= 4/3   ;    /* promote to inetger only in the right hand side result */

float d2= 4.0/3 ;    /* promote to float      */
float d3= 4/3.0 ;
float d4= 4.0/3.0; 

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#11137

On 10/28/2011 9:06 PM, 88888 Dihedral wrote:
> float d1= 4/3   ;    /* promote to inetger only in the right hand side result */
No, that's integer arithmetic, result promoted to float.

>
> float d2= 4.0/3 ;    /* promote to float      */
> float d3= 4/3.0 ;
> float d4= 4.0/3.0;

Technically, the first two are promote to double, truncate to float.
The third is already double, truncate to float.

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#11138

red floyd於 2011年10月29日星期六UTC+8下午1時14分07秒寫道：
> On 10/28/2011 9:06 PM, 88888 Dihedral wrote:
> > float d1= 4/3   ;    /* promote to inetger only in the right hand side result */
> No, that's integer arithmetic, result promoted to float.
> 
> >
> > float d2= 4.0/3 ;    /* promote to float      */
> > float d3= 4/3.0 ;
> > float d4= 4.0/3.0;
> 
> Technically, the first two are promote to double, truncate to float.
> The third is already double, truncate to float.
------------------------------------------------------
int x=3;
int y=4;

float  d = x/y         ;  
float  d= ((float)x)/y ; 

/* whether  the compiler knows x,y are constants up to now ? */ 

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#11142

On 10/28/2011 11:27 PM, 88888 Dihedral wrote:
>
>
> red floyd於 2011年10月29日星期六UTC+8下午1時14分07秒寫道：
>> On 10/28/2011 9:06 PM, 88888 Dihedral wrote:
>>> float d1= 4/3   ;    /* promote to inetger only in the right hand side result */
>> No, that's integer arithmetic, result promoted to float.
>>
>>>
>>> float d2= 4.0/3 ;    /* promote to float      */
>>> float d3= 4/3.0 ;
>>> float d4= 4.0/3.0;
>>
>> Technically, the first two are promote to double, truncate to float.
>> The third is already double, truncate to float.
> ------------------------------------------------------
> int x=3;
> int y=4;
>
> float  d = x/y         ;
> float  d= ((float)x)/y ;
>
> /* whether  the compiler knows x,y are constants up to now ? */
>

What's your point? 4.0 and 3.0 are *DOUBLE* constants.

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