Path: csiph.com!usenet.pasdenom.info!news.redatomik.org!newsfeed.xs4all.nl!newsfeed1.news.xs4all.nl!xs4all!newsgate.cistron.nl!newsgate.news.xs4all.nl!post.news.xs4all.nl!not-for-mail Return-Path: X-Original-To: python-list@python.org Delivered-To: python-list@mail.python.org X-Spam-Status: UNSURE 0.282 X-Spam-Level: ** X-Spam-Evidence: '*H*': 0.58; '*S*': 0.15; 'subject:How': 0.09; '-10': 0.09; 'cc:addr:python-list': 0.10; '"we': 0.16; 'from:addr:rosuav': 0.16; 'from:name:chris angelico': 0.16; 'ground,': 0.16; 'tweak': 0.16; 'wrote:': 0.16; 'cc:2**0': 0.21; 'cc:addr:python.org': 0.21; 'balancing': 0.22; 'am,': 0.23; '2015': 0.23; 'sat,': 0.23; 'header:In-Reply-To:1': 0.24; 'checking': 0.27; 'specify': 0.27; 'message-id:@mail.gmail.com': 0.28; 'class': 0.33; 'received:google.com': 0.34; 'could': 0.35; 'but': 0.36; "didn't": 0.37; 'subject:: ': 0.37; 'version': 0.38; 'end': 0.39; 'wanted': 0.39; 'some': 0.40; 'your': 0.60; 'safe': 0.63; 'fuel': 0.66; 'college': 0.67; 'gain': 0.81; '180': 0.84; 'chrisa': 0.84; 'degrees,': 0.84; 'hurry,': 0.84; 'thrust': 0.84; 'to:none': 0.90; 'burn': 0.91; 'captain': 0.91; 'careful': 0.91; 'dennis': 0.91; 'played': 0.91 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:cc :content-type; bh=G6gU/qfDF+5uSEHW+MHLRiR3HLhsFG7DAYU550XzM4o=; b=ngbtDsPrMSWpSeJTHTh4ZIv6nMN6EPnQ3c664miiQYS2LSLfQ32mawt7b7FCqlx7y9 e9oogBtmR/BIIA1BBjzAsO1IyfLqnoiDQvW7RnzDR/3GEStzu0OGMhC3C8tMAuD+qGWs 6wCMJVLfVRyfmph5FFqSm+bLJdfH/lxtE4ohyVNKYJPk6SOtqkzdOLzEsIO6q5P+YnSS 6Oc+7BhzUn1Mcv7wToYai9VEziFRDE0QHSPf/fYXYq2SO3koTiJ/RBKswg9Wgt7R1/hn IeMLz1kQYKCYeqA+h6Dvu1IgeCx92Xo0hvm97m8b9QEi3ckrv+j4kQdAJQ2ec8fosYNt A+5w== MIME-Version: 1.0 X-Received: by 10.50.61.241 with SMTP id t17mr1079692igr.34.1433550776453; Fri, 05 Jun 2015 17:32:56 -0700 (PDT) In-Reply-To: References: <1bad33c0-a728-4345-883b-505f84d8ea9b@googlegroups.com> Date: Sat, 6 Jun 2015 10:32:56 +1000 Subject: Re: How to inverse a particle emitter From: Chris Angelico Cc: "python-list@python.org" Content-Type: text/plain; charset=UTF-8 X-Mailman-Approved-At: Sat, 06 Jun 2015 08:04:52 +0200 X-BeenThere: python-list@python.org X-Mailman-Version: 2.1.20+ Precedence: list List-Id: General discussion list for the Python programming language List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Newsgroups: comp.lang.python Message-ID: Lines: 23 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1433570693 news.xs4all.nl 2855 [2001:888:2000:d::a6]:42709 X-Complaints-To: abuse@xs4all.nl Xref: csiph.com comp.lang.python:92174 On Sat, Jun 6, 2015 at 10:10 AM, Dennis Lee Bieber wrote: > That is in the same class as the "lunar lander" game on my college > mainframe... > > It did not do validity checking of inputs, with the result that one > could do > > -10 lbs thrust at 180 degrees > > and GAIN fuel while decelerating. Hah! The version I played didn't allow you to specify 180 degrees, although it did allow negative burns. So you could tweak your fuel supply by careful negative burning, but it required some balancing work to actually come to a safe landing. Of course, if you wanted to just quit out in a hurry, all you have to do is a straight-down burn of -9999999, and bam, you're on the ground, with a Captain Haddock style of "We shall end up by arriving, I suppose". ChrisA