Re: integral to floating point conversion

2016-07-03 Thread Observer via Digitalmars-d
On Sunday, 3 July 2016 at 13:41:27 UTC, Ola Fosheim Grøstad wrote: On Sunday, 3 July 2016 at 11:49:15 UTC, Andrei Alexandrescu wrote: Well to be more precise here's what I'm looking for. When you compare an integral with a floating point number, the integral is first converted to floating point

Re: integral to floating point conversion

2016-07-03 Thread Ola Fosheim Grøstad via Digitalmars-d
On Sunday, 3 July 2016 at 11:49:15 UTC, Andrei Alexandrescu wrote: Well to be more precise here's what I'm looking for. When you compare an integral with a floating point number, the integral is first converted to floating point format. I.e. for long x and double y, x == y is the same as double

Re: integral to floating point conversion

2016-07-03 Thread Andrei Alexandrescu via Digitalmars-d
On 07/03/2016 05:52 AM, Guillaume Boucher wrote: On Sunday, 3 July 2016 at 09:08:14 UTC, Ola Fosheim Grøstad wrote: On Saturday, 2 July 2016 at 20:17:59 UTC, Andrei Alexandrescu wrote: So what's the fastest way to figure that an integral is convertible to a floating point value precisely (i.e.

Re: integral to floating point conversion

2016-07-03 Thread Ola Fosheim Grøstad via Digitalmars-d
On Sunday, 3 July 2016 at 09:52:38 UTC, Guillaume Boucher wrote: This is the correct answer for another definition of "precisely convertible", not the one Andrei gave. True, I see now that he actually asked for unique representation, not precisely convertible.

Re: integral to floating point conversion

2016-07-03 Thread Guillaume Boucher via Digitalmars-d
On Sunday, 3 July 2016 at 09:08:14 UTC, Ola Fosheim Grøstad wrote: On Saturday, 2 July 2016 at 20:17:59 UTC, Andrei Alexandrescu wrote: So what's the fastest way to figure that an integral is convertible to a floating point value precisely (i.e. no other integral converts to the same floating p

Re: integral to floating point conversion

2016-07-03 Thread Ola Fosheim Grøstad via Digitalmars-d
On Saturday, 2 July 2016 at 20:17:59 UTC, Andrei Alexandrescu wrote: So what's the fastest way to figure that an integral is convertible to a floating point value precisely (i.e. no other integral converts to the same floating point value)? Thanks! -- Andrei If it is within what the mantissa

Re: integral to floating point conversion

2016-07-03 Thread Matthias Bentrup via Digitalmars-d
On Saturday, 2 July 2016 at 20:30:03 UTC, Walter Bright wrote: On 7/2/2016 1:17 PM, Andrei Alexandrescu wrote: So what's the fastest way to figure that an integral is convertible to a floating point value precisely (i.e. no other integral converts to the same floating point value)? Thanks! --

Re: integral to floating point conversion

2016-07-02 Thread Simen Kjaeraas via Digitalmars-d
On Saturday, 2 July 2016 at 20:49:27 UTC, Andrei Alexandrescu wrote: On 7/2/16 4:30 PM, Walter Bright wrote: On 7/2/2016 1:17 PM, Andrei Alexandrescu wrote: So what's the fastest way to figure that an integral is convertible to a floating point value precisely (i.e. no other integral converts

Re: integral to floating point conversion

2016-07-02 Thread ketmar via Digitalmars-d
On Saturday, 2 July 2016 at 20:17:59 UTC, Andrei Alexandrescu wrote: So what's the fastest way to figure that an integral is convertible to a floating point value precisely (i.e. no other integral converts to the same floating point value)? Thanks! -- Andrei bool isConvertible(T) (long n) if

Re: integral to floating point conversion

2016-07-02 Thread Walter Bright via Digitalmars-d
On 7/2/2016 1:49 PM, Andrei Alexandrescu wrote: On 7/2/16 4:30 PM, Walter Bright wrote: On 7/2/2016 1:17 PM, Andrei Alexandrescu wrote: So what's the fastest way to figure that an integral is convertible to a floating point value precisely (i.e. no other integral converts to the same floating p

Re: integral to floating point conversion

2016-07-02 Thread MakersF via Digitalmars-d
On Saturday, 2 July 2016 at 20:49:27 UTC, Andrei Alexandrescu wrote: On 7/2/16 4:30 PM, Walter Bright wrote: On 7/2/2016 1:17 PM, Andrei Alexandrescu wrote: So what's the fastest way to figure that an integral is convertible to a floating point value precisely (i.e. no other integral converts

Re: integral to floating point conversion

2016-07-02 Thread Andrei Alexandrescu via Digitalmars-d
On 7/2/16 4:30 PM, Walter Bright wrote: On 7/2/2016 1:17 PM, Andrei Alexandrescu wrote: So what's the fastest way to figure that an integral is convertible to a floating point value precisely (i.e. no other integral converts to the same floating point value)? Thanks! -- Andrei Test that its ab

Re: integral to floating point conversion

2016-07-02 Thread Walter Bright via Digitalmars-d
On 7/2/2016 1:17 PM, Andrei Alexandrescu wrote: So what's the fastest way to figure that an integral is convertible to a floating point value precisely (i.e. no other integral converts to the same floating point value)? Thanks! -- Andrei Test that its absolute value is <= the largest unsigned v

integral to floating point conversion

2016-07-02 Thread Andrei Alexandrescu via Digitalmars-d
So what's the fastest way to figure that an integral is convertible to a floating point value precisely (i.e. no other integral converts to the same floating point value)? Thanks! -- Andrei