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UWA week 24 - 1st semester, 1st exam week

photo Re: 2018 Q2b (all 3)
Mon 8th Jun, 9:55am, ANONYMOUS
On a similar note, could something like 2018 2a be questioned? Although I did manage to find the answer online I can't seem to find it in the lecture notes.

UWA week 23 - 1st semester, study break

photo Re: Past paper (all 5)
Thu 4th Jun, 6:54pm, ANONYMOUS
ANONYMOUS wrote: Have you tried the search function?

UWA week 21 - 1st semester, week 11

photo Re: Determining if a route is not valid in a given day? (all 10)
Thu 21st May, 5:01pm, ANONYMOUS
I used Edward's approach, but if Chris is marking with only 20 stations I reckon you'd be find with a timer.
photo Re: How to check if the timetable has changed after the server has already started? (all 11)
Thu 21st May, 12:43pm, ANONYMOUS  O.P.
Thanks everyone, I think I know what to do now.
photo How to check if the timetable has changed after the server has already started? (all 11)
Thu 21st May, 11:15am, ANONYMOUS
Right now each server gets its timetable by reading its respective file upon startup. However, if the file then gets updated while the server is running, the server will keep using the old timetable and you'd have to restart the server to use the new...
photo Re: Project query string parameters (all 7)
Tue 19th May, 10:49am, ANONYMOUS
ANONYMOUS wrote: Why don't you just generate the current time once in the source server, then send that time around in your UDP messages?

UWA week 20 - 1st semester, week 10

photo Re: How do avoid buffer space error in Python? (all 10)
Thu 14th May, 4:01pm, ANONYMOUS  O.P.
If you're getting the first instead of the fastest route then you might not run into that problem since I'd assume you'd be sending fewer messages. I just created a send function like this: def send_udp_message(message, dest): result = None while...
photo Re: Hint request: Getting the fastest path (all 12)
Thu 14th May, 3:56pm, ANONYMOUS
You could try sending a message back to a previous station only once you've visited all the neighbours for the current station. As an example, let's say you start at station A and travel to station B. Station B's neighbours are station C, station D, and...
photo Re: How do avoid buffer space error in Python? (all 10)
Wed 13th May, 11:04pm, ANONYMOUS  O.P.
Alright, will do so.
photo Re: How do avoid buffer space error in Python? (all 10)
Wed 13th May, 9:05am, ANONYMOUS  O.P.
Where would you use the s and where would you use the r? I'd think that using both of them in the same UDP message would just give the same number of s's and r's. Also, how many stations/connections will you be using when marking?
photo Re: How do avoid buffer space error in Python? (all 10)
Wed 13th May, 5:46am, ANONYMOUS  O.P.
The error comes when I try to send a UDP message: udp_sock.sendto(("...").encode(), (HOST, NEIGHBORS[neighbor])). I tried adding a delay at the beginning of this line but the program was still running after five minutes, and that seems unreasonably long...
photo Re: How do avoid buffer space error in Python? (all 10)
Tue 12th May, 3:33pm, ANONYMOUS  O.P.
Also to illustrate, my messages aren't excessively long either. Trying to send this message via UDP causes me to get an error, and it's only 189 characters: $TRAVEL_FROM$15:32$DAYS_SINCE$1$TARGET$TerminalG$VISITED$7036-15:31$7030-16:16$7022-18:39$7038-...
photo How do avoid buffer space error in Python? (all 10)
Tue 12th May, 3:20pm, ANONYMOUS
My code works for small numbers of stations, but once I hit about 20 I get an error saying OSError: [Errno 55] No buffer space available. I've set my buffer size to 1000000 like so: data, addr = udp_sock.recvfrom(1000000), but I still get the error. Does...
photo Re: Can we assume that there will always be a route to a given station? (all 3)
Tue 12th May, 3:17pm, ANONYMOUS  O.P.
Alright, thanks for the clarification.
photo Can we assume that there will always be a route to a given station? (all 3)
Tue 12th May, 11:42am, ANONYMOUS
Also, can we assume that we'll always be given a station that exists?
photo Re: Performance and marks (all 7)
Mon 11th May, 9:45am, ANONYMOUS
This approach of course would be to get the fastest journey, if just any journey is needed then the program could just return as quickly as possible.
photo Re: Performance and marks (all 7)
Mon 11th May, 9:42am, ANONYMOUS
My idea was more along the lines of finding the best result that you can get within one minute and then returning, whether that's with four stations or 40000. The other approach would be to return once you're sure you've reached all the required stations...

UWA week 19 - 1st semester, week 9

photo How to close a socket upon keyboard interrupt in Python? (all 4)
Sun 10th May, 2:39pm, ANONYMOUS
Hi, I've been having difficulties getting my sockets to closed upon keyboard interrupt in Python. My code looks something like this (udp_sock and tcp_sock are global variables): if __name__ == '__main__': try: t1 = threading.Thread(target=udp_listener)...
photo Re: Performance and marks (all 7)
Sun 10th May, 2:35pm, ANONYMOUS
Does that mean our project can run for one minute even if there's only like four stations?
photo Re: Project Design Question (all 10)
Sun 10th May, 2:33pm, ANONYMOUS
Thanks Edward and Chris, I'll go with linking the name and UDP port then.
photo Re: Project Design Question (all 10)
Fri 8th May, 11:19pm, ANONYMOUS
Thanks Chris. Clearing the file only applies if you're keeping a file on disk so that's irrelevant now. However, I'm still a bit confused as to how you'd link a UDP port to its name. The way I understand it each server would only need to keep track of...
photo Re: Project Design Question (all 10)
Fri 8th May, 2:21pm, ANONYMOUS
Hey Chris, Had a question about how you'd implement something like a phonebook. For each server you get its name and UDP port, so my idea is that you could write each server's name and UDP port in an external file as soon as the server starts? Is this...
photo Are we allowed to use the threading module in Python? (both)
Fri 8th May, 1:40pm, ANONYMOUS
As title suggests.
photo Re: setsockopt works for some server instances but not others (all 5)
Wed 6th May, 11:37am, ANONYMOUS  O.P.
Each servers are using TCP ports 2200 and 2201 (I haven't incorporated any of the port numbers after the first port argument). But I checked using portsinuse.h and neither 2200 or 2201 show up as being used - I wouldn't expect so given that the code runs...
photo Re: setsockopt works for some server instances but not others (all 5)
Tue 5th May, 12:43pm, ANONYMOUS  O.P.
That doesn't seem to fix the problem. If I put setsockpot after bind, what ends up happening is that the server with the higher TCP port doesn't update, and the server with the lower TCP port gives a "localhost refused to connect" error in the browser,...
photo setsockopt works for some server instances but not others (all 5)
Mon 4th May, 7:22pm, ANONYMOUS
Hi guys, I'm trying to call setsockpot for my socket as follows in Python: with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s: s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1) s.bind((HOST, TCP_PORT)) This is so I don't have to change...

UWA week 18 - 1st semester, week 8

photo Is using the sockets module allowed for Python? (both)
Sun 3rd May, 9:34pm, ANONYMOUS
It seems fairly low level but I just want to be sure.
photo Re: nc server receives weird request from browser (all 3)
Fri 1st May, 10:45am, ANONYMOUS  O.P.
Thanks Chris, that fixed the problem.
photo nc server receives weird request from browser (all 3)
Fri 1st May, 10:12am, ANONYMOUS
I tried going through the Getting Started guide. I'm able to start the nc server, but when I open https://localhost:4444 the attached image is the request I get in the terminal (it doesn't look like the one in the guide). Then when I try to terminate the...
photo How will the project account for routes with multiple stops? (both)
Mon 27th Apr, 10:20pm, ANONYMOUS
trains leaving that station, including the destination of each, and the (multiple) times throughout each day that each bus leaves the station and arrives at the destination. As an example, let's say we wanted to take the 950 bus to the city. The destination...

UWA week 17 - 1st semester, week 7

photo Any starter code for the project? (all 4)
Sun 26th Apr, 6:19pm, ANONYMOUS
I've read the project description and I have literally no idea how to get started. I can vaguely understand what the project is asking me to do, but I have no idea how any of the steps would be implemented using code. I've also done the labs and kept...

UWA week 16 - 1st semester, mid-semester break

photo Re: End of semester exam (all 14)
Thu 16th Apr, 10:28am, ANONYMOUS
Any updates on ungraded pass Chris?
photo Re: Lecture 6 Recording (all 7)
Thu 16th Apr, 10:26am, ANONYMOUS
ANONYMOUS wrote: Also wanted to know when the lecture will be out. I've been looking forward to it for the last two weeks.

UWA week 15 - 1st semester, non-teaching week

photo Re: End of semester exam (all 14)
Tue 7th Apr, 4:12pm, ANONYMOUS
Please keep us updated Chris. Also worth considering is that UNSW is giving pass/fail for all their engineering courses (including CS), and they're accredited by the ACS. Surely if UNSW is doing it then UWA can do it too.
photo Re: End of semester exam (all 14)
Mon 6th Apr, 11:17pm, ANONYMOUS
Related to my previous question, I'm taking Computer Science as a second major, and according to the ACS (https://www.acs.org.au/cpd-education/accredited-courses.html) the Computer Science major is only accredited if taken as a degree-specific major in...
photo Re: End of semester exam (all 14)
Mon 6th Apr, 9:44pm, ANONYMOUS
If I don't care about being accredited by the ACS, can I just take the ungraded pass and not be "accredited"?

UWA week 14 - 1st semester, week 6

photo Where to find week six lecture? (both)
Sun 5th Apr, 11:22pm, ANONYMOUS
I checked on Echo, but there doesn't seem to be a lecture for week six.

UWA week 13 - 1st semester, week 5

photo Re: Weighting for project this semester (all 8)
Wed 25th Mar, 9:46pm, ANONYMOUS  O.P.
Thanks Chris.
photo Re: Solutions for labs (all 6)
Wed 25th Mar, 9:46pm, ANONYMOUS  O.P.
When are the solutions for lab 3 coming out?
photo Weighting for project this semester (all 8)
Tue 24th Mar, 12:50pm, ANONYMOUS
According to the CITS3002 website it's 40% for the team-based project and 60% for the exam. However, the project is apparently team-based, but the UWA Guild says that team-based projects can have a maximum 30% weighting for the combined mark. https://issuu.com/uwastudentguild/docs/know_your_rights_guide?fbclid=IwAR06l4NjEtuhYQq-IBnsgu91rksIDNIn1RrbWDZmtHND6V9qYJz8giBH8Is...

UWA week 12 - 1st semester, week 4

photo Re: Installing cnet on your own laptop (all 28)
Mon 16th Mar, 12:51pm, ANONYMOUS
Not sure. Installed the cnet in a new folder at ~/cnet, but adding that directory to the file /etc/paths doesn't seem to affect the output of echo $PATH. I'm not sure whether that's the right way to add a path though.
photo Re: Installing cnet on your own laptop (all 28)
Mon 16th Mar, 1:02am, ANONYMOUS
I'm having trouble installing on Mac too. I don't get any errors if I use sudo make clean && sudo make && sudo make install. But if I try running sudo make doc I do get these errors: mkdir: /home/httpd/html/cnet: Operation not supported mkdir: /home/httpd/html/cnet/images:...

UWA week 10 - 1st semester, week 2

photo Solutions for labs (all 6)
Sat 7th Mar, 12:03am, ANONYMOUS
Hi Chris, will solutions be posted for the labs for this unit?
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