The perpetual calendar
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From: Peter T. Daniels on 1 Mar 2010 08:45 On Mar 1, 8:25 am, "J. Clarke" <jclarke.use...(a)cox.net> wrote: > On 2/28/2010 2:09 PM, David Harmon wrote: > > On Wed, 24 Feb 2010 09:56:25 -0500 in alt.usage.english, tony cooper > > <tony_cooper...(a)earthlink.net> wrote, > >> As far as I can tell, the only employers that are closed on > >> President's Day are government offices, schools, and banks. To the > > > There is no such holiday as "President's Day" to US government offices. > >http://www.opm.gov/Operating_Status_Schedules/fedhol/2010.asp > > While that is a true statement, it does not alter the fact that the post > office was closed on that date. Welcome to the world of a.u.e. nitpickery.
From: Peter T. Daniels on 1 Mar 2010 08:47 On Mar 1, 8:35 am, tony cooper <tony_cooper...(a)earthlink.net> wrote: > On Mon, 1 Mar 2010 04:51:09 -0800 (PST), "Peter T. Daniels" > > > > > > <gramma...(a)verizon.net> wrote: > >> >Don't be ridiculous. Washington's Birthday is February 22 (Gregorian), > >> >and Presidents' Day was observed on Feburary 15. > > >> Your foot's bleeding again. Have the bullet removed before the wound > >> festers. > > >> Washington's Birthday was officially shifted to the third Monday in > >> February by the Uniform Monday Holiday Act in 1971. The federal > >> holiday has never officially been changed to President's Day. > > >> The change was made 39 years ago. You've never noticed? > > >In some states, we think Lincoln was pretty important, too. > > >We note that you moved to a part of the country where Lincoln is > >despised. > > If there's an anti-Lincoln sentiment in Florida I'm not aware of it. > To be honest about it - and I should be when Abe is involved - Lincoln > really isn't the subject of many conversations around here. That says something right there. > Is your "We" an insular "We" or a Royal "We"? For what group do you > speak? New Yorkers, linguists, or generally-considered-to-be-potty > cross-posters? If you have so much trouble interpreting simple English, why do you hang around a.u.e.? The "we" are the residents of New York and Illinois.
From: James Silverton on 1 Mar 2010 09:39 jmfbahciv wrote on Mon, 01 Mar 2010 07:37:01 -0500: > Peter Moylan wrote: >> jmfbahciv wrote: >>> James Silverton wrote: >> >>>>> You always could "start" at numbers other than one. Or >>>>> are you talking about the actual memory assigned to the >>>>> array? >>>> Yes, there were ways of doing that but when you defined an array >>>> with, say, >>>> >>>> DIMENSION A(100) >>>> >>>> The array elements were A(1) to A(100). >>>> >>>> I think it was Fortran77 where, say, >>>> >>>> REAL (0:99) :: A >>>> >>>> became a valid declaration. >>>> >>> Thanks. I swear I read the 77 ANSI proposal but I don't >>> remember this stuff. That one had to cause bugs. >> >> I've never used Fortran 77, but I don't see how that would >> cause bugs. If the array bounds have to be declared, the >> compiler can insert checks for subscripts being out of >> bounds, and in fact that is what is done in most of the >> modern programming languages I know something about. > Those checks are usually done at compile time, not runtime. Your > FORTRAN example implies that indexing doesn't have to be an integer. > That's what I was thinking about when I made the > statement about "had to cause bugs". Someday I should reread the 77 > standard again. The REAL statement refers to the contents of the array, You could also have, say, INTEGER (-33:33) :: A. I believe Fortran90 allows non integer indices but how they worked, I don't know, since I only scanned a book on that. I had been using C and C++ for a while then. Fortran compilers did not check for "out of bounds" errors as far as I remember. -- James Silverton Potomac, Maryland Email, with obvious alterations: not.jim.silverton.at.verizon.not
From: J. Clarke on 1 Mar 2010 10:33 On 3/1/2010 8:35 AM, tony cooper wrote: > On Mon, 1 Mar 2010 04:51:09 -0800 (PST), "Peter T. Daniels" > <grammatim(a)verizon.net> wrote: > >>>> Don't be ridiculous. Washington's Birthday is February 22 (Gregorian), >>>> and Presidents' Day was observed on Feburary 15. >>> >>> Your foot's bleeding again. Have the bullet removed before the wound >>> festers. >>> >>> Washington's Birthday was officially shifted to the third Monday in >>> February by the Uniform Monday Holiday Act in 1971. The federal >>> holiday has never officially been changed to President's Day. >>> >>> The change was made 39 years ago. You've never noticed? >> >> In some states, we think Lincoln was pretty important, too. >> >> We note that you moved to a part of the country where Lincoln is >> despised. >> > > If there's an anti-Lincoln sentiment in Florida I'm not aware of it. > To be honest about it - and I should be when Abe is involved - Lincoln > really isn't the subject of many conversations around here. Florida is a bit different from the rest of the South in terms of its history--while technically it was a slave state it wasn't admitted to statehood until 20 years or so before the Civil War and prior to that time it had been a refuge for escaped slaves, so Floridians never had much of a problem with Lincoln. > Is your "We" an insular "We" or a Royal "We"? For what group do you > speak? New Yorkers, linguists, or generally-considered-to-be-potty > cross-posters? > >
From: Evan Kirshenbaum on 1 Mar 2010 11:28
Peter Moylan <gro.nalyomp(a)retep> writes: > Evan Kirshenbaum wrote: >> Peter Moylan <gro.nalyomp(a)retep> writes: >> >>> Admittedly the common "off by one" errors are often caused by >>> zero-based subscripting. With most programming languages, though, >>> such an error will make itself evident the first time you run the >>> program, when you run off the end of the array; and the exception >>> information will quickly lead you to the cause of the crash. It's >>> safe to declare subscript ranges in any way that is natural to the >>> application, as long as the generated code includes range >>> checks. The main thing that makes C so unsuitable for real-world >>> applications is the paucity of run-time checks. >> >> The existence of which, of course, along with the concommitant >> overhead, being one of the main reasons that other languages were >> considered unsuitable for real-world applications. >> >> Fast, safe, and easy to write a compiler for. Pick two. >> > I take your point, but the world has changed since such decisions > were made. Yeah, but a lot of the code bases in use go back that far, and rewriting from scratch is a difficult proposition. The slide from C to C++ is relatively easy and allows you to encapsulate safety in library classes, but changing the language more radically is a whole 'nother ball of wax. > The computer I'm now using has a processor that's about 100 times as > fast as the one in the first PC I ever had. Either you're a lot younger than I thought, or it's *way* more than 100. I believe that the last time I looked at it, processor speed (in terms of work that can be performed) was essentially on a Moore's Law curve, which gives you a factor of ten every five years. (It's not just cycle time; it's how much you can get done in a cycle due to the instruction set, pipelining, multiple cores, etc.) > I'm doing a job at present that requires a lot of real-time graphics > processing, and it turns out that we have a lot of spare processor > time. And the genetic programming runs I was doing last year (in a system written in C++) had the processor pegged (on 4 cores each for 16 machines) for hours. There's a spectrum. I do most of my programming in Java these days, but every time I look at rewriting that system, I throw up my hands. There's just no way it can match the performance (largely through templates and inlining) or maintainability. (Java's designers made some silly (but understandable) choices when they added parameterized types. (Some good ones, too, don't get me wrong.)) > Besides, it's been true for a number of years now that software > written in high-level languages often runs faster (up to about a 5% > improvement) than the same software written in C. That's because > modern compilers do a lot of code optimisation, but with a low-level > language a lot of optimisation possibilities aren't applicable. When I was in school, C was considered an HLL, and the same point was made: since control flow is explicit, you can do a lot more optimization. Which optimizations did you have in mind that don't apply to C++? > As for range checks: some processors now in use do a range check in > a single machine language instruction. The same instruction as the fetch or set? That would probably be enough. Which processors do that? (I'm woefully behind on modern processor architectures.) > Your "easy to write a compiler for" is more to the point. With the > kinds of processor that are typically used for embedded > applications, compilers are available for exactly one language, so > the programmer has no choice. -- Evan Kirshenbaum +------------------------------------ HP Laboratories |On a scale of one to ten... 1501 Page Mill Road, 1U, MS 1141 |it sucked. Palo Alto, CA 94304 kirshenbaum(a)hpl.hp.com (650)857-7572 http://www.kirshenbaum.net/ |