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##### Activity
• Nov 09 2020 13:10
labarba closed #217
• Nov 09 2020 12:27
Wajiha11 commented #217
• Nov 09 2020 12:27
Wajiha11 opened #217
• Dec 22 2019 20:45
mesnardo edited #216
• Dec 22 2019 20:44
mesnardo closed #216
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mesnardo closed #213
• Dec 22 2019 20:44

mesnardo on master

Minor changes * [Module 2, Les… (compare)

• Dec 04 2019 01:43
mesnardo labeled #216
• Dec 04 2019 01:43
mesnardo opened #216
• Mar 12 2019 20:30
nightwolfer1 commented #174
• Mar 12 2019 19:32
labarba commented #174
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nightwolfer1 commented #174
• Feb 21 2019 13:27
bknaepen synchronize #167
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• Nov 27 2018 17:01
mesnardo opened #215
• Oct 03 2018 15:22
Chao8219 opened #214
• Oct 03 2018 00:03
Chao8219 opened #213
• Aug 30 2018 20:53

labarba on format

Chris Short
@ChristopherShort
re using Chrome...but then I'd have to finally create a config file (waiting until Matplotlib accepts them easily before doing so) Some in the class already struggling without challenges of creating config file. But will go where the good professors set requirements :-). And Lorena - thanks - you seem to be going above call of duty for this course.
FredInChina
@ReblochonMasque
GTG now, I'll check back in later.
Lorena A. Barba
@labarba
Thanks ChristopherShort. Hope to see you in the discussion board, if it ever resuscitates
FredInChina
@ReblochonMasque
I must be dense, but I can't find a link to download Lanchester's "Aerodonetics" pdf... any help?
Ashutosh Purushottam
@apurushottam
This is interesting !!
Hal Snyder
@DrXyzzy
Ashutosh Purushottam
@apurushottam
Thanks DRXyzzy :) .. the link is working
FredInChina
@ReblochonMasque
Wonderful, thanks DrXyzzy. :)
scshepard
@scshepard
I borrowed this tweet, so not sure if will help/address the MathJax issues:Scott Hanselman @shanselman · Jun 23
Exploring cross-browser math equations using MathML or LaTeX with MathJax http://hnsl.mn/1j8H5u5
Gregorio
@jgfdsa
HI! I'm starting with this great course... does anyone know if its possible to get a certificate or Statement of Accomplishment?. Thanks in advance and cheers!
Lorena A. Barba
@labarba
We were not planning to give a certificate at the end of the course, but are willing to reconsider this question later.
Gregorio
@jgfdsa
Thanks for fast replying!. Anyway I will follow the course, I find it very interesting. But if I may request it, would be very nice and useful to have at least a Statement of Accomplishment.
Krishna Bhogaonker
@00krishna
The materials and syllabus look really interesting. Just a suggestion for the future, but it would be great to also include a module on Cython so that you can offload some of the computation to C++ numerical libraries or the direct CUDA C++ interface. There are pure python libraries for some of this stuff, like pycuda or parallel python but usually those wrappers are totally impossible to debug. I also really like the cython ability to let me visualize the data directly in OpenGL. That way, again, I don't have to rely on all of these outdated python wrappers for OpenGL that are not actively maintained and again hard to debug.
Lorena A. Barba
@labarba
This is a beginner course ...
We are planning to have some material on CUDA Python via Numba
aarrietac
@aarrietac
Starting the day with Pyhon :smile:
Ian Hawke
@IanHawke
Ah, we've gone to $\gamma$ for angles?
Hal Snyder
@DrXyzzy
There's a feature request open for MathJax here. :smile:
some discussion of it at gitterHQ/gitter
Lorena A. Barba
@labarba
We had a huge argument with all my students about signs, it lasted like two hours!
We should've had you, Ian: you're the mathematician!
The signs of the angles turns out to be important in the whole derivation, and we were mixing things: glide angle is always positive… the glider is assumed to be going down (as weight is the driving force opposing drag). But in the analysis of the particle in a curved path, we needed theta positive upwards!
Ian Hawke
@IanHawke
I think I clocked the positivity of z issue (NOTE: someone on the forum complained about the notebook throwing an assertion error; it's precisely the positivity of z that this is about, and I think should be expected). I was always thinking even functions in the small angle expansion, though, so I missed the sign issue.
Lorena A. Barba
@labarba
The explanations needed a little more precision, but the derivation is right.
We follow Milne-Thompson (1966) and I added a note explaining that. He uses theta for the trajectory angle, positive up. That carries to equations (10), where sin theta= - dz/ds … note minus
DrXyzzy --- did you request MathJax to be available within the markdown in Gitter?
Hal Snyder
@DrXyzzy
Yes.
Lorena A. Barba
@labarba
That would be nice.
@IanHawke -- We cannot reply in the forums right now: it's broken. But yes, the error in the trajectory plotting code is probably because of the parameters they picked.
Ian Hawke
@IanHawke
Yes - I've lost some long replies in the forums the past couple of days (when testing, I should remember to keep them short...).
Maybe we should set a mini-exercise to evaluate the energy loss due to numerical error?
GTG.
Lorena A. Barba
@labarba
I've got that written up!!! (and it's actually an energy gain)
Actually, what I have written up is just the proof that T_{n+1}=T_n(1 + w^2 Delta t ^2) -- one page of algebra
But you suggest giving that to students to do?
Sigurd Angenent
@SigurdAngenent
Hi, thanks for running this MOOC. It seems like quite a project. I think that the first python script can be simplified. In phugoid.py you compute the radius of curvature, the center of the osculating circle and then rotate the point by a small angle. But you could also use the diffeqs dx/ds = cos(theta) and dz/ds=sin(theta) to increment x and z
Sigurd Angenent
@SigurdAngenent
OK, the indentation in my previous post is gone. I don't see how to do that. I don't understand github wel enough to upload the modified-phugoid.py file..
Alistair Walsh
@alistairwalsh
github is not exactly intuitive :-) I would suggest a tutorial like https://try.github.io/levels/1/challenges/1
aarrietac
@aarrietac
Yeah! This is an amazing tutorial for git! Thanks @alistairwalsh :clap:
scshepard
@scshepard
Anaconda install observation; I'm using the Prof recommended site (https://store.continuum.io/cshop/anaconda/) but fell into a couple of Dark Places; first, the user interface is "odd"; suggest you "hover" over the link to verify the file name before clicking. Also (it may be a Windows or Windows 8.1 issue) had to edit the system PATH because Anaconda set its self as a "user" not system install (i.e: Had to delete the old python PATH in system; it is in my user PATH, but system PATH over-rode it). Now, all works great! (for what it's worth, I'm running Python 3.4)
Lorena A. Barba
@labarba
anyone there wish to test our new installation ???
I need testers
We're testing a new course platform for the course, with the latest version of Open edX and will migrate the course tomorrow if all tests pass!!!
Help!
Uncustomized with our style, but all course state until last Friday in the new installation: Please try to break it ....
within reason ...
Lorena A. Barba
@labarba
if it passes, we'll add the custom style, delete the course and re-migrate it from the live version.
Alistair Walsh
@alistairwalsh
I can check, what exactly do you want me to install. I have native Mac, Linux and Windows as well as virtual machines. Does it need to be full native or is installing on the virtual machines enough?