Re: [Python-ideas] SI scale factors alone, without units or dimensional analysis

Ah, always mess up micro = 6/9 until I think about it for half a second. Maybe a "n" suffix could have saved me there ;) For "long" numbers there's the new _ so you can say 0.000_000_1 if you so preferred for 0.1 micro (I generally see _ as more useful for high-precison numbers with more non-zero

Re: [Python-ideas] SI scale factors alone, without units or dimensional analysis

On Sat, Oct 29, 2016 at 12:43 PM, Nick Timkovich wrote: > From that page: > >> User-defined literals are basically normal function calls with a fancy >> syntax. [...] While user defined literals look very neat, they are not much >> more than syntactic sugar. There is not

Re: [Python-ideas] SI scale factors alone, without units or dimensional analysis

>From that page: > User-defined literals are basically normal function calls with a fancy > syntax. [...] While user defined literals look very neat, they are not much > more than syntactic sugar. There is not much difference between defining > and calling a literal operator with "foo"_bar and

Re: [Python-ideas] SI scale factors alone, without units or dimensional analysis

I'd certainly be interested in hearing about how this has worked with C++, but this would certainly make scientific code less easy to misuse due to unclear units. -Ryan Birmingham On 28 October 2016 at 16:45, Sven R. Kunze wrote: > On 28.10.2016 22:06, MRAB wrote: > >> On

Re: [Python-ideas] SI scale factors alone, without units or dimensional analysis

On 28.10.2016 22:06, MRAB wrote: On 2016-08-26 13:47, Steven D'Aprano wrote: Ken has made what I consider a very reasonable suggestion, to introduce SI prefixes to Python syntax for numbers. For example, typing 1K will be equivalent to 1000. Just for the record, this is what you can now do in

Re: [Python-ideas] SI scale factors alone, without units or dimensional analysis

On 2016-08-26 13:47, Steven D'Aprano wrote: Ken has made what I consider a very reasonable suggestion, to introduce SI prefixes to Python syntax for numbers. For example, typing 1K will be equivalent to 1000. Just for the record, this is what you can now do in C++: User-Defined Literals

Re: [Python-ideas] SI scale factors alone, without units or dimensional analysis

On Sun, Aug 28, 2016 at 11:37:00AM +0100, Paul Moore wrote: > And if you're concerned about larger numbers, such as 160, and > the need to count zeroes, I'd argue that you should name such a > constant - and Python 3.6 will allow you to write it as 16_000_000_000 > in any case, making

Re: [Python-ideas] SI scale factors alone, without units or dimensional analysis

On 27 August 2016 at 23:39, Arek Bulski wrote: > They can be used simply out of convenience, like 4K is a shorthand for 4000. > And 9G is definitely easier to write and *therefore less prone to error* > than a full literal. I dispute "less prone to error". Like it or not,

Re: [Python-ideas] SI scale factors alone, without units or dimensional analysis

Ken Kundert writes: > The rule is you cannot give unit without a scale factor, and the > unity scale factor is _, so if you wanted to say 1 mol you would > use 1_mol. 1mol means one milli ol. These look a little strange, > but that is because the use they unit scale factor, which is the >

Re: [Python-ideas] SI scale factors alone, without units or dimensional analysis

SI units are a standard that was kind of imposed top down on the computer science community. But we learned to use KB MB so why no keep the defacto standard we already have? Kibibytes and mibibytes were never really adopted. 1K == 1000 1KB == 1024 1M == 1000**2 1MB == 1024**2 Suffixes, simple.

Re: [Python-ideas] SI scale factors alone, without units or dimensional analysis

>> Proposal number two: don't make any changes to the syntax, but treat these as *literally* numeric scale factors. >> k = kilo = 10**3 >> M = mega = 10**6 >> G = giga = 10**9 >> >> int_value = 8*M float_value = 8.0*M >> fraction_value = Fraction(1, 8)*M >> decimal_value = Decimal("1.2345")*M

Re: [Python-ideas] SI scale factors alone, without units or dimensional analysis

Steven D'Aprano wrote: Obviously if I write 1.1K then I'm expecting a float. Why is it obvious that you're expecting a float and not a decimal in that case? The SI units are all decimal, and I think if we support these, we should insist that K == 1000, not 1024. For binary scale factors,

Re: [Python-ideas] SI scale factors alone, without units or dimensional analysis

Okay, so I talked to Guido about this, and all he was trying to convey is that there is an extremely high bar that must be reached before he will consider changing the base language, which of course is both prudent and expected. I'd like to continue the discussion because I believe there is some

Re: [Python-ideas] SI scale factors alone, without units or dimensional analysis

On 8/26/2016 8:47 AM, Steven D'Aprano wrote: This leads to my first proposal: require an explicit numeric prefix on numbers before scale factors are allowed, similar to how we treat non-decimal bases. 8M # remains a syntax error -1 for the syntax, +1 for keeping it an error 0s8M #

Re: [Python-ideas] SI scale factors alone, without units or dimensional analysis

On 8/26/16, Steven D'Aprano wrote: [...] > from scaling import * > int_value = 8*M > float_value = 8.0*M > fraction_value = Fraction(1, 8)*M > decimal_value = Decimal("1.2345")*M [...] > Disadvantages: none I can think of. Really interesting idea, but from my POV a little

Re: [Python-ideas] SI scale factors alone, without units or dimensional analysis

On 2016-08-26 14:34, Chris Angelico wrote: On Fri, Aug 26, 2016 at 10:47 PM, Steven D'Aprano wrote: [snip] Or if that's too heavy (two whole characters, plus the suffix!) perhaps we could have a rule that the suffix must follow the final underscore of the number: 8_M #

Re: [Python-ideas] SI scale factors alone, without units or dimensional analysis

On Fri, Aug 26, 2016 at 5:47 AM, Steven D'Aprano wrote: > Ken has made what I consider a very reasonable suggestion, to introduce > SI prefixes to Python syntax for numbers. For example, typing 1K will be > equivalent to 1000. > > However, there are some complexities that

Re: [Python-ideas] SI scale factors alone, without units or dimensional analysis

On Fri, Aug 26, 2016 at 10:47 PM, Steven D'Aprano wrote: > (1) Are the results floats, ints, or something else? > > I would expect that 1K would be int 1000, not float 1000. But what about > fractional prefixes, like 1m? Should that be a float or a decimal? > > If I write

[Python-ideas] SI scale factors alone, without units or dimensional analysis

Ken has made what I consider a very reasonable suggestion, to introduce SI prefixes to Python syntax for numbers. For example, typing 1K will be equivalent to 1000. However, there are some complexities that have been glossed over. (1) Are the results floats, ints, or something else? I would