(Thankfully this topic has warped into Friday.) As to which endian is more 'natural', it occurred to me that one hurdle an English speaker has in learning German is the disconnect between some numerals and the corresponding verbiage: we write '24' but say 'vierundzwanzig'. This endian reversal is limited; numbers over one hundred still contain the big value(s) on the left.
I can't say I fully understand all the posts on this subject--I could not really explain endianness (Wikipedia term) fully to someone else--but I'm on surer footing than I was before. Thanks for that! . . J.O.Skip Robinson Southern California Edison Company Electric Dragon Team Paddler SHARE MVS Program Co-Manager 323-715-0595 Mobile 626-543-6132 Office ⇐=== NEW [email protected] -----Original Message----- From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf Of David W Noon Sent: Friday, June 16, 2017 8:44 AM To: [email protected] Subject: (External):Re: RFE? xlc compile option for C integers to be "Intel compat" or Little-Endian On Thu, 15 Jun 2017 20:33:13 -0500, John Mckown ([email protected]) wrote about "Re: RFE? xlc compile option for C integers to be "Intel compat" or Little-Endian" (in <caajsdjg3xp-2cyaiea6xpre22z+ql60wwml2sy_o5xoo2bz...@mail.gmail.com>): > On Thu, Jun 15, 2017 at 5:05 PM, Frank Swarbrick < > [email protected]> wrote: > >> The following link gives a few reasons why little-endian might be >> preferred: https://softwareengineering.stackexchange.com/questions/ >> 95556/what-is-the-advantage-of-little-endian-format. As a human I >> still prefer big-endian, regardless of any perceived advantages for >> little-endian! >> > > I must disagree with the "as a human" portion of the above. It is more > a "as a speaker of a Western European language using Arabic numering" > ( in UNICODE these are called "European digits") . We got our > writing direction, left to right, from the Romans (I'm not sure where > they got it). But we got our positional numbering system from the > Hindus via the Arabs (thus the "Arabic Numerals"). We write the most > significant digit on the left because they Arabs did it that way. But > the Arab languages are written right to left. So, from their view > point, they are reading the least significant digit first. I.e. Arabic > Numerals are written "little endian" in Arabic. Europeans just wrote > it the same physical direction because that's how they learned it. > Using "little endian" is actually easier. This would only be reflective of little-endian ordering if it used full bit reversal. Computers use bits, so any Arabic ordering would require all the bits to be reversed, not the bytes. > How we do it now: 100 + 10 = 110. In our minds we must "align" the > trailing digits (or the decimal point). But if it were written 001 + > 01, you could just add the digits in the order in which we write them > without "aligning" them in your mind. In the example, add the first > two 0s together. Then add the second 0 & second 1. Finally "add" the > last 1 just by writing it out. In a totally logical universe, the > least significant digit (or bit if we are speaking binary) should be > the first digit (or bit) encountered as we read. So the number one in > an octet (aka byte) , in hex, would be written 0x10 or in binary as > b'10000000'. This is not the way computers do arithmetic. Adding, subtracting, etc., are performed in register-sized chunks (except packed decimal) and the valid sizes of those registers is determined by architecture. In fact, on little-endian systems the numbers are put into big-endian order when loaded into a register. Consequently, these machines do arithmetic in big-endian. As someone who was programming DEC PDP-11s more than 40 years ago, I can assure everybody that little-endian sucks. > And just to > round out this totally off topic weirdness, we can all be glad that we > don't write in boustrophedon style (switch directions every line) > ref: http://wordinfo.info/unit/3362/ip:21 That's all Greek to me. -- Regards, Dave [RLU #314465] *-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-* [email protected] (David W Noon) *-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-* ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
