Re: Motion 46: finalise interval literals
On 12 Jul 2013, at 08:42, Vincent Lefevre wrote:
>> I think that this phrase from the text is sufficient:
>> "One ulp equals one unit in the last place of the number m as written."
>
> Perhaps, however it isn't very well said: "the number m as written"
> still refers to a number, not a string or representation. I would
> prefer something like:
>
> One ulp equals the unit (weight) of the last written digit.
I was brought up from elementary school with "place" having this technical meaning, as in "Ones place", "Tens place", "Hundreds place" etc., so it is actually preciser language than "digit". The "place" is the slot where you write a "digit".
So I prefer to keep "place". However it may not be familiar to non-native English speakers? I would welcome a suggested sentence of explanation to add, along with examples like those below.
>> It defines ulp not in terms of value but in terms of string. So
>> 0? = [-0.5,+0.5]
>> 0.0? = [-0.05,+0.05]
>
> But I think that such examples would be useful.
>> Moreover the grammar doesn't match (1). According to (1), "011" is
>> 9 in C, but according to the grammar, it is 11, in the context of
>> ratNumLit.
Oh dear, this octal convention is C? I thought it was some outlandish language hardly anyone had heard of.
John Pryce