Hi Jakub,
> I believe the wording is correct. The outcome is not always the same:
> the leading digit zero is allowed only for non-normalized numbers.
If I am understanding this correctly, shouldn't the man page say:
"The digit before the decimal point is specified for nonnormalized
numbers, and nonzero numbers but other‐wise unspecified for normalized
numbers."
I replaced the first occurence of "unspecified" with "specified" and
inserted "numbers"
after "nonzero". To make it even simpler:
"The digit before the decimal point is unspecified when the number is
normalized and the digit is zero; otherwise, the digit is specified."
Is this correct?
Also, why is it possible that the following numbers are printed if
the floating-point number is 1.0?
0x8.0p-3
0x4.0p-2
0x2.0p-1
Why are there multiple possibilities if the IEEE 754 standard is being
used? I did not know that was a possibility.
Thank you for your time,
Rohit Saily
On Mon, May 18, 2020 at 2:49 PM Rohit Saily <rohit@xxxxxxxxxxxxxx> wrote:
>
> Hi Jakub,
>
>
> > I believe the wording is correct. The outcome is not always the same:
> > the leading digit zero is allowed only for non-normalized numbers.
>
> If I am understanding this correctly, shouldn't the man page say:
>
> The digit before the decimal point is specified for nonnormalized
> numbers, and nonzero numbers but other‐wise unspecified for normalized
> numbers.
>
> I replaced the first occurence of unspecified with specified and inserted numbers
> after nonzero. To make it even simpler:
>
> The digit before the decimal point is unspecified when the number is
> normalized and the digit is zero; otherwise, the digit is specified.
>
> Is this correct?
>
> Also, why is it possible that the following numbers are printed if
> the floating-point number is 1.0?
>
> 0x8.0p-3
> 0x4.0p-2
> 0x2.0p-1
>
> Why are there multiple possibilities if the IEEE 754 standard is being
> used? I did not know that was a possibility.
>
>
> Thank you for your time,
>
> Rohit Saily
>
>
> On Mon, May 18, 2020 at 11:38 AM Jakub Wilk <jwilk@xxxxxxxxx> wrote:
>>
>> Hi Rohit!
>>
>> * Rohit Saily <rohit@xxxxxxxxxxxxxx>, 2020-05-16, 18:04:
>> >I am having difficulty understanding a sentence in the PRINTF(3) man
>> >page's explanation of the 'a' and 'A' conversion specifiers, more
>> >specifically it is the following sentence:
>> >
>> >>The digit before the decimal point is unspecified for nonnormalized
>> >>numbers, and nonzero but other‐wise unspecified for normalized
>> >>numbers.
>> >
>> >My confusion arises due to the fact that the two posible cases are
>> >described with the same outcome,
>>
>> I believe the wording is correct. The outcome is not always the same:
>> the leading digit zero is allowed only for non-normalized numbers.
>>
>> For example, printf("%a", 1.0) could produce any of these outputs:
>>
>> 0x8.0p-3
>> 0x4.0p-2
>> 0x2.0p-1
>> 0x1.0p+0
>>
>> but not:
>>
>> 0x0.8p+1
>>
>> On the other hand, assuming the IEEE 754 binary64 format,
>> printf("%a\n", 0x0.8p-1022) could produce any of these:
>>
>> 0x8.0p-1026
>> 0x4.0p-1025
>> 0x2.0p-1024
>> 0x1.0p-1023
>> 0x0.8p-1022
>>
>> --
>> Jakub Wilk
