From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-0.9 required=5.0 tests=BAYES_00,FORGED_GMAIL_RCVD, FREEMAIL_FROM autolearn=no autolearn_force=no version=3.4.4 X-Google-Thread: 103376,2a34b7ad6c6a0774 X-Google-NewGroupId: yes X-Google-Attributes: gida07f3367d7,domainid0,public,usenet X-Google-Language: ENGLISH,ASCII Path: g2news1.google.com!postnews.google.com!t20g2000yqa.googlegroups.com!not-for-mail From: =?ISO-8859-1?Q?Elias_Salom=E3o_Helou_Neto?= Newsgroups: comp.lang.ada Subject: Re: Efficiency of code generated by Ada compilers Date: Fri, 13 Aug 2010 08:10:37 -0700 (PDT) Organization: http://groups.google.com Message-ID: <12ce49e6-169e-4e35-b82f-27de0d9b1ceb@t20g2000yqa.googlegroups.com> References: <1jn1a4o.1dfllwo1uin3imN%csampson@inetworld.net> <1jn36d6.se2f0g1edjjnyN%csampson@inetworld.net> <61f149b9-00ff-40cd-9698-01e69fdc5c0f@v15g2000yqe.googlegroups.com> NNTP-Posting-Host: 143.107.183.162 Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable X-Trace: posting.google.com 1281712237 1784 127.0.0.1 (13 Aug 2010 15:10:37 GMT) X-Complaints-To: groups-abuse@google.com NNTP-Posting-Date: Fri, 13 Aug 2010 15:10:37 +0000 (UTC) Complaints-To: groups-abuse@google.com Injection-Info: t20g2000yqa.googlegroups.com; posting-host=143.107.183.162; posting-account=8auP9QoAAACkSx2qxJhP83KA6-tg78E8 User-Agent: G2/1.0 X-HTTP-UserAgent: Mozilla/5.0 (X11; U; Linux x86_64; en-US) AppleWebKit/533.4 (KHTML, like Gecko) Chrome/5.0.375.99 Safari/533.4,gzip(gfe) Xref: g2news1.google.com comp.lang.ada:13222 Date: 2010-08-13T08:10:37-07:00 List-Id: On Aug 13, 12:08=A0pm, Elias Salom=E3o Helou Neto wrote: > On Aug 12, 5:21=A0pm, "(see below)" wrote: > > > > > > > On 12/08/2010 20:23, in article m28w4bfxdy....@pushface.org, "Simon Wri= ght" > > > wrote: > > > csamp...@inetworld.net (Charles H. Sampson) writes: > > > >> Simon Wright wrote: > > > >>> csamp...@inetworld.net (Charles H. Sampson) writes: > > > >>>> =A0 =A0 =A0I then overloaded "+" and "-" for (Bearing, Turn_Angle)= arguments > > >>>> and Bearing return value. =A0In those functions is where the mod 3= 60 > > >>>> occurred. =A0(Actually, mod 360.0, as it were.) > > > >>> Depending on what is doing the turning, in our application that wou= ld > > >>> in some cases have to be mod 720.0 ... > > > >> =A0 =A0 =A0I'm puzzled. =A0Unless you're very careful, intermediate = calculations > > >> could result in a quasi-Bearing of more than 360 degrees but I'm pre= tty > > >> sure most programmers on my project would have been surprised to see= a > > >> real bearing of 360 degrees or more. > > > > A tracker radar like this one (hope the link will work) might be able= to > > > turn through an unlimited number of revolutions, or (with a more > > > mechanical design) there might be a limit on how many revs it could > > > manage. So if it's currently pointing 10 degrees to starboard, how mu= ch > > > further can it go before having to unwind? > > > > I agree that this is Training, not Bearing, of course. > > > >http://www.artisan3d.co.uk/static/bae_cimg_radar_Fi_latestReleased_ba.= .. > > > dar_Fi_Web.jpg > > > I think quantum mechanics codes would require angles mod 720 for spin 1= /2 > > particles. 8-) > > > -- > > Bill Findlay > > chez blueyonder.co.uk > > Well, we are definitely drifting away from the original question. So > much that I am considering to give up reading answers from this > post... > > Anyway, someone prematurely implied that I may be doing premature > optimization. The fact is that I do know, from profiling, how > important is _not_ to range check in my specific application, so I > will try to give you a "bottom line" of what have been said that > really matters to me. > > 1) You can, in more than one way, tell the compiler to suppress most > (any?) checks, but people do not advise to do so. Even if I say that I > do need that :( > > 2) It is not necessary for the compiler to actually suppress any > checking! It seems that the LRM demands the compiler to allow you to > misunderstood something here. > > I am having a fairly good impression of Ada's features, but the effort > it would take to learn the language may eventually not pay off. > > Thank you, > Elias. > > P.S: Multidimensional _arrays_ are not multidimensional _matrices_ > neither are them MD _images_. The two latter are far more specific > classes and the last case even needs to be templated in, say, pixel > type, etc. Sorry, but where it is written > ask for the suppression, but it does mandate the compiler to actually > skip such checks. Well, this is, to say the least, funny - unless I you should read ask for the suppression, but it does NOT mandate the compiler to actually skip such checks. Well, this is, to say the least, funny - unless I Sorry again, Elias.