I hate this Macbook’s touch top bar which puts a send button directly above the delete key.
> On Aug 2, 2017, at 2:50 PM, Dave Fisher <dave2w...@comcast.net> wrote: > > Hi Folks, > > A peanut gallery look at NaN which is really a bit encoding for various kinds > of floating point number errors like underflow, overflow, divided by 0, etc. > In my Fortran past life we used XMISS as a special valu Value. Essentially undefined. IEEE had very particular definitions and Apple published a book about SANE. At any rate what you guys are observing is by design: NaN always results in false in any comparison. And it is a number. But it is not a number in floating point so much as it is an error condition. https://stackoverflow.com/questions/1565164/what-is-the-rationale-for-all-comparisons-returning-false-for-ieee754-nan-values https://people.eecs.berkeley.edu/~wkahan/ieee754status/IEEE754.PDF My father complained about when the IBM 360 came out in the early 1960’s he had to go to doubles because the IBM architecture went from 6 - 6 bit words for a single to 4 - 8 bit words. The practical result was twice as much magnetic tape both length and number of reals. Regards, Dave > >> On Aug 1, 2017, at 3:21 PM, Greg Dove <greg.d...@gmail.com> wrote: >> >> Yes it does. NaN is an 'instance' of the Number type (even though it is >> 'Not a Number' ;) ) >> >> >> On Wed, Aug 2, 2017 at 10:18 AM, Harbs <harbs.li...@gmail.com> wrote: >> >>> Interesting. >>> >>> I’m not sure that I realized that NaN passes that test. Does it? >>> >>>> On Aug 2, 2017, at 1:12 AM, Greg Dove <greg.d...@gmail.com> wrote: >>>> >>>> I agree undefined works the same as NaN for many things for example, but >>> it >>>> fails on very basic things like if (x is Number) >>> >>> >
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