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On 07/03/2023 09:43, rich_met wrote:
Hi there I should be showing up as "rich_met" and I'm down West Cornwall. I realised I've been "ploughing a lone furrow" for far too long so reaching out to the group. 20 years ago was in Cambridge and member of Linux User Group there. In meantime, not been member of any club or group association with any computing. Where am I at now... I code mostly in emacs-lisp so it's right there in the emacs text-processor. eg. "topmost" "user-level" program for doing (Euler-Bernoulli) beam looks like this (defun beam-fmax-rhs-simple-cload (shs-width shs-depth shs-thk shs-length shs-stl-sigmamax ;; typically yield stress ) "for an RHS - max.force it will bear in central load simple beam best if all dimensions & values in SI / metres, etc Order of args matches order going into ma2nd calc / fn" (simple-support-dblbeam-loadcap (beam-moment-capacity shs-stl-sigmamax (beam-sect-mod-z-d (ma2nd-rhs-b-h-t shs-width shs-depth shs-thk) shs-depth)) shs-length)) so you can see at a glance I go 2nd moment of area (purely geometric property) v section modulus (purely geometric property) v beam moment capacity (combine geometry and material property) v"simple" centrally loaded beam capacity (given length, force it will bear)which is the normal progression of a beam calculation. An example of "real world" design I made and got used is herehttp://www.weldsmith.co.uk/tech/struct/210314_ebbeam_drillplat/19_drillplat_calcs.html"Cantilever drilling platform - analysis using beam calculations" I also do Finite Element Analysis modelling for stresses and strains - simply use an integrated software package for doing that. eg.http://www.weldsmith.co.uk/tech/struct/210216_bcfwtt_fea3d/210216_bcfwtt_fea3d.html"FEA3D : BCFWTT RHS beam top surface around test weld" "BCFWTT" is this physical "real world" testhttp://www.weldsmith.co.uk/tech/struct/210122_fwtest_rig/210122_fwtest_testrig.htmlRecently I did this which converts decimal GPS coordinates - eg. Google Maps to "human-usable" / "nautical chart" Degrees Minutes and Seconds entire code: (defun lat-long-degdeci-to-dms (latdeci longdeci) (format "%s %s %s"(abs-degdeci-to-abs-deg-min-sec (abs latdeci) (if (minusp latdeci) 'S 'N))" " ;; easy jdi customisable way to separate lat. and long. output(abs-degdeci-to-abs-deg-min-sec (abs longdeci) (if (minusp longdeci) 'W 'E))))(defun abs-degdeci-to-abs-deg-min-sec (absdegdeci dirncardinal) "Deg-decimal to DMS format output" (if (minusp absdegdeci) "error - cannot handle negative arguments" (let ((decix60 (* (mod absdegdeci 1) 60)))(format "%03dd %02d' %04.1f'' %s" (truncate absdegdeci) (truncate decix60) (* (mod decix60 1) 60) dirncardinal))))For example - Berry Head lighthouse is at (North, East) 50.39954886056384, -3.483553379652956 (lat-long-degdeci-to-dms 50.39954886056384 -3.483553379652956) "050d 23' 58.4'' N 003d 29' 00.8'' W" which is correct - that is the position of Berry Head lighthouse on a nautical chart which uses the "WGS84" datum. If you paste 050 23' 58.4" N 003 29' 00.8" W into Google Maps it will show a pin on the lighthouse... But all of this done in total isolation (learned Lisp-style programming from a book 20 years ago with Paul Graham's "On Lisp" http://www.paulgraham.com/onlisp.html) So have no idea whether there might be much better ways of achieving the goal. Computers and Computing - 10 year old "mac-air" still going and couple of years ago managed to get it to upload lots more software from "fink" site, so all happiness there. Which has left the "Raspberry Pi" computer, which works wonderfully, neglected. By the way I learned Linux when needed a supercomputer in the 1990's. Had doing 10's of hours runs when then "Windows95" would "fall-over" about every 4 hours and couldn't really be used at all for ad-hoc programming (no segmentation -> allocated space, and only that space, in which a program is permitted to run). I'd have some use of an embedded device - eying the Raspberry Pi card which came with the computer Measure something like hydraulic pressure from a sensor, log it and maybe control something to do with that hydraulic pressure. Anyone interested in any of these things? -- The Mailing List for the Devon & Cornwall LUG FAQ: https://www.dcglug.org.uk/faq/
Hi Rich.Bit late here but do some playing with Lisp - retired now and using the opportunity to play with stuff I started to dig into for work 40 years ago so just dug out lisp-kit and found a pdf copy of the book online. Also dug out the old aima lisp code to have a play. Found some Prolog for it too but thats seriously out of date. Kinda fun to get both historical ends of AI to meet!
Up near Holsworthy which is in the north and west of Devon but apparently not in North Devon or West Devon!
Tom te tom te tom -- The Mailing List for the Devon & Cornwall LUG FAQ: https://www.dcglug.org.uk/faq/