Mtg 3/26: Tue-19-Jan-2021

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Zoom Audio Transcript

• Good afternoon. Okay, so, as promised a bit late, but I have We're going to use this link for the rest of the semester. So I've included that on the web page now. Take out the zoom invitations link. Okay, so here's our web page. Right now. So here's my schedule. Not going anywhere between I kind of sitting at the same desk one From Minutes between it's not It's not just relaxing. Anyway, We'll get we'll get it worked out. So it helps. Now I think that I've got the zoom link. Distributed So I'm going to take the office hours out of my your courses counter And these in here and I'll put the the input the office link. Here, I think. To figure out how to do that. In a reasonable way. Okay. So there's a Link here. Because You can click on that. If I have an office, our schedule, then I should be at the in that room. Here with the office. Here's the zoom meeting link for the semester. We don't need the zoom meeting invitations anymore. meeting today. So I had some discussion with It support about how to set these up. And they're trying to convince me that I didn't need to do it the way that I did it last week. So I changed it. But now I think that I do need to do what I did last week. So I think I need to have a forum for every meeting. So the idea is just to collect your thoughts about This meeting. Before the next one. So, So a change from what I did last on Thursday. Was too. So if I make some And to make make them open for comments are interested in proposing. Not 24 hours after the meeting finishes but 24 But midnight. As a day before the meeting of the day of the meeting. Planning is So banded Monday at midnight for Tuesday meetings and Wednesday midnight for Thursday meetings. Where we can review them. So have the Details of your assignments up and we can discuss them on Thursday. Now I think love start this week. I'm not sure about that, but I think it is so So there's a separate your courses. For These links there. There. Oh data. But there's not gonna be a mid term. Having the syllabus ready and I do mostly but I didn't get the chance to check the dates. So let me just show you What it looks like so far. All right, fix the links for the date the dates and I think I fixed the links, but just the dates need to be worked on. Let me show you that. I didn't ask consider doing today. Meetings on Tuesdays and Thursdays one to 215 Go until April 15 My offices in zoom and here's a link to my office hours. I didn't include the semester, if you if you hover over the link. You'll see there's more detail here because I didn't want to go over the line. For the if you just look at this one. That gives you Yeah, so just pick the semester. If you go to that link. Please, if you click on it, you'll go to the right to the semester. Anyway, And I have my office telephone number here. So if you leave me a message on my phone in the office. I'll get a text that you've left a message for me in my office because I haven't been in my office. For a long time. And I have to just check these Sections in the times for the labs. That's one thing I need to fix. And then the final exams. Well, I need to fix. So here's our courses. The first one in here is my website to support the course this semester. So, Description multimedia is use of computers to integrate text, graphics video animation and sound an interactive experience of course will introduce You to the different technology associated with elements and multimedia, you will gain an appreciation of the strengths of each multimedia element and be able to combine these elements into finished work. Okay, and recommended books. So getting started with p five is one I believe there's an earlier version of this is completely online. And then generative design some Sketches Visualize program and create with JavaScript, and P five jazz. So this first published in German. There's an English version. Now,
• And
• Go look it up, put the link to the sketches that has go with the editor. As well. Okay, so those are things you Might find interesting as you explore these ideas. But not required. So the individual assignments. I should say individual
• Can I do that.
• 20% so the project. And the project can be done with individually or as a small group. There 20% allowed work will be 20% So engagement with meetings is 10% Participation is 5% And the final exam will be 25% you must pass the file to pass the course. Which is not meant To be a threat or You know that I'm going to try and fail people so I can make good on this requirement. It's just that the final exam is a way to Evaluate your learning for this semester so that That's what I that's what it's intended to support So I'm eager to Have your input about what kind of Form the final exam will take And we have some options. I think And we can discuss it over the coming weeks and then I have some discretion five plus or minus 5% and there's the research credit up to 2% We talked about last day. I love this online. I just had a question. What's the difference between engagement with meetings and participation like
• How do we differentiate between those two.
• Well, so the engagement of meetings is writing Small notes to perform Making the forum posts. And Attendance, we will start attendance on Thursday. Coming to class and Participating in class.
• And the forum opens onI'm sorry, because I was not here on the first day of classes because I wasSo I'm not really sure how the forum works yet.
• Okay, so let's go and So any other questions about that. Any questions on this.
• No, just also just have to question you could also can specify when the forum closes, because I was just wondering about the form
• One which closed.
• When the engagement forum causes and your classes.
• Yeah, so it'll close The night. At midnight or The day before the next meeting. So I had that setup for the for the Tuesday for the meeting to And then I changed it. BECAUSE PEOPLE AND IT support. That I could. I didn't have to. I could save some work. And now I'm not convinced that that's going to save any Africa that I can save myself any work. But the one thing I change. I'll change from Tuesday, where I said you have to make a post before Friday at Now for the Thursday meeting. I'll say make a post before Monday at 2359 So I can look at them before the meeting on Tuesday. And then for the Tuesday meetings, you can make a post before Wednesday at 2359 And the way that I'm going to do this. So there's going to be 20 There are 26 meetings altogether, but I'm leaving some slack to To get everyone started So I'll take the Top 20 In calculating the 10 marks of the for engagement. So I Should just go to the Let me switch back another one. Me. What's your cat's name Emily. you're muted. That's a good combination learning and napping. Okay, so let's go to the forum here.
• Just a quick question regarding the syllabus. Would you be able to make visible to us case, we need to look for reference.
• Yeah, I'm gonna post it once I fix The dates.
• Oh, I see. Okay, gotcha. Thanks. You're welcome.
• I just ran out of time.
• Today,
• Okay, so I'm going to switch this back to Me because I have a feeling about this. So I'm just going to do it. I'm going to duplicate At 2359 I gotta try this, that we're not going to force subscription.
• And equation for these forums. Each time you create a forum will get notification on your courses like through The email. Me at all.
• So it should be. Set it should should be on the calendar. Because I set a due date for But I'll mention that
• Maybe I canSee what I can do together.
• A reminder about these in our
• Meeting.
• Okay, so the idea is maximum. So you won't get a mark, you'll get zero. If you don't write something before the due date and time. And to have you've written something that shows engagement with a meeting. And Also have one available to be if you've written something that doesn't seem to be engaged. So if you say something like The topic of the meeting was interesting. I had trouble understanding the meeting topic. So you've written something you've put some effort into writing something but You're not Engaging with the meeting so Let's give you one for that. So the idea is, so there are 26 altogether. So I said, the top 20 meetings top 20 marks. Will go to make one out of give you a market of 10 for that. Okay, that makes sense. I don't know what makes sense here. Because I said these things. Getting a bit repetitive and I have to have something in here. Okay, so let me just check now whether this is in the Calendar, or in our upcoming events. Clear Yes, man. I saw your hand go up and then I listened. Sure. Okay, so let's clear enough. Still, welcome to use microphones, if you like. There's only 30 of us here. I think 2525 is not a scary number isn't So here, let's go through a semi our last meeting. So I meant to having trouble with my internet connection today. So answer restart and I was going to post a video of the following the entropy video About encoding. And relating the entropy to compression So I'll do that after our meeting today. And then you can you have a chance to look at it before Thursday, that would be great. So here's my Here's a summary. And I we found my wife and I found out that We thought, wow, all their dogs look the same. This is actually Elgar here when he was still more of a puppy. Should I play the video Travis asked Allah I'm not sure how much time is there, but So surprised to See that our puppy is Already a celebrity enough people are gonna want is popped renter Yeah, probably. There's a problem with audio. There wasn't there. Didn't hear the audio.
• Now,
• So don't worry about that. I won't show you more videos. I just thought of it.
• Anyway,
• So here's my summary is a binary guessing game. Okay, I can make sense as in my scribbles Right. So we talked about, if there's only one card.
• You
• Get two numbers for using what it's like if you're using one that we can represent two values. So if we had the one card here. You say, is your number on this card. Thanks for that tip about video Desktop idea. I'll probably not show very many videos in zoom tools we'll see So the question here is, is your number on this card. So pick a number between zero and one pick either zero or one is your number on this card. Yes. So your numbers, one that no you didn't know that your number zero. So it's not very exciting but shows you our goals. And then the two cards. Will be one in three and two, and three. So if we said no to both of these cards. The zero Said yes to this one, it would be One. Ever said yes to both of them, it would be three. Never said no to this one, yes to this one, it would be to Make sense Couple of things to do. So we did the example with three cards here. So what is the table look like with the yeses and NOEs if you make four cards and if you make five cards so So, what, what happens to this table. What does the table look if we had a forest card if we filled in the column. Yeah, so we have eight entries. Now, and so we make 16 of
• Them.
• But how do we decide What do we do with these These eight entries that we have Can we do something simple to Do anything we can copy and paste or use our previous work.
• What I like to do first call keeps alternate snow. Yes. The second follows this turn to know yeses two yeses. The third Nose than yeses and its New column then be a follow up. Yes.
• There's a pattern here. Certainly.
• Yeah, the same thing. So first, go and do one thing. And then next one is 0011 calm before the phones and so on.
• Yeah. So what I would do is I would copy These eight entries and just paste them. Below here and then You tell me if this is what you said. I think it's a little bit different. But then I would put notes in front of here. I would put nose in the first in front of these eight values. And then I put yeses in front of the eight values that I copied and pasted So that's just my own particular take on it. Yeah, so we're just, we're building out this pattern. So there was a comment about whether this is like a truth table. And I'm Not sure that I, I didn't I didn't get into came out. It seems like A circuit design kind of Idea. Instead of truth table. This is We're just we're enumerating we're writing out the values in binary, and then Under the V column. We're adding we're creating we're expressing them as as decimal values. So where is the truth table it say with the inputs. The whys and the entry is inputs and the outputs value would be V. And then I would also The wire and then there We're, we're we're counting in binary. And then it's writing them in decimal. Can I explain that better than it sounded To me.
• Yep. Okay.
• So we talked about encoding a little bit in a Second, as well. So what we're doing here vs at the trick is doing some encoding. So we're asking the participant or the subject or the volunteer or the Whatever assistant Whatever adjective is most appropriate for asking that person to Go number in decimal between zero and 15 when we're using four cards. So, What the idea is, is we're asking them yes or no questions. We're asking them to encode their decimal number in binary. So that, that's the surprising thing for people is, how did you get that. Well, you told me you know derivatives and binary, you told me your number a binary So that's If that makes sense. Only the only trick. Then, once people tell you the numbers, be able to add up. Value of the cards. So if they say Yes to the one card and yes to the four card, then you have to be able to add One plus four. And keep that straight until the end of the trick. Go one time I remember this not working, as I'm sure as a youngster who is Kind of Having who gets the number was not being truthful to me. Anyway, So the other thing to think about is What if we flip the card. So instead of having 1357 On the first card for Christmas. These three cards. We had 0246 on the card and how and things Change. Made the cards that way. So just something to think about. Any problems, but it's just Just a little bit. Different way of thinking about it. Okay, so In terms of encoding. So I took this definition so I took the definition from Wikipedia. I thought that was Traditionally, General to Okay, so we can know that we have. If we using example three beds. So we have eight different values. So we could use the eight values to represent The numbers themselves so 0037 would be the values associated with those Points. We could also use We could also Have different values that we associate with This is the encoding part It for 00 here. And we really We Have a number 28 For example, Much anymore. We have a bit color. Access 24 bits so If we have Eight bits to store pixel. Then we have 256 possible values for it. So we can either treat them as gray scale. As intensities between zero and 255 Or between zero and one. If you want to Normalize it So, Divide divide through the Value by 255 ticket as a Fraction between zero to one. So we can say that the percentage of Gray's it's in a black and white image or Are we can Say we have 256 wise. So let's create a color palette. So the fact that we have 256 values means that we could have 256 different For color full fully expressed colors available to us. So we can represent 236 24 colors. I'm not sure if I'm making this better or not. But the idea is you can save some space because they're only storing one bit or eight bits, instead of 24 bits every pixel And we're just looking up so we just have to store one The power of 256 colors with 24 bits and the rest of the image data itself can be stored using only eight bits. So that's one way that we can do an encoding and there's some other ways. So we'll catch up again. We'll come back to that later in the semester. So then storing text. Ideas, you have to convert You have to come up with a system of storing the values like the letters A through said With some numerical equivalents. So for just interested in capital letters. We can use five bits to get the 26 letters. Or if you want the lowercase letters to then we have We need to add another good service with six bits. We can have 6464 spots in our table. In her Her look up between lowercase, uppercase letters and And the code reason to access So it's 64 characters and we have Door for punctuation and so on. Then we'd like to add numbers zero through nine. And numerical operators. Plus minus and so on. So, then we've exceeded six So then we go to seven bits that gives us 128 Characters and that's what I'll ask is defined So let me show you. A very nice representation of the ASCII This graphic here from pre 1972 printer manual Credible character starting it Starting with space. An exclamation point in court and consign and Dollar sign and Percent sign and Season asterisks and so on. So the nice and some nice features of this are You can see that the numbers zero through nine. zero through nine. Are the lower four bits are zero through nine. And then if we know we're in So we just have to take those four bits out So you can do some bitwise operations to manipulate this easily So if you want to go between Capital letters capital A. lowercase a See that they're the same. four bits are the same. And then we just have to do a shift. To get Free shift right well anyway. So we just need to switch this from zero to one. And then we get the capital letters. And then the first two columns. Or Type control characters that Are not often use these days, but they're with us for Well, we have line feed, and Backspace. And the bell. So, some of them are still us but not so many of them. That helps to understand ASCII So what So what if you want to write something in French with axon. It grew axon and The deal and Any other see other oh So complex IBM tool. So there's no there's no room to put them in here. So what do we What do we end up doing. Or what what's a possible solution.
• Why the ass kicking into play.
• OrSomething else.
• So,
• We do have the extended team, which is

Zoom Chat Transcript

• good afternoon
• Good afternoon
• afternoon
• good afternoon
• Hello!
• good afternoon!
• Anyone know if we have to record our own attendance for these meetings?
• I think that's just for labs
• I thought there’s a separate CS 205 LAB module on urcourses that also has the attendance sheet. But our CS 205 page also has one?
• good, how about you?
• good, how about you?
• good
• Ellie
• she's learning and napping at the same time
• she is super cute :)
• yes
• yep
• yes
• yes
• yes
• Yes
• Yes
• I meant it's clear
• yea
• yup
• yes
• It appears that watching videos this way doesn't work for audio.
• You need to check off enable desktop audio when you start screen sharing if you want the video sounds to go through
• Yes
• yup
• yes
• it will still work -
• unicode
• yes
• Sometimes!
• yup
• yes
• my favourite "Image not found"
• ripped page
• Yes
• I thought the video was very helpful!
• it was a good video, well explained
• have a good day!
• Thanks, see you!
• Thanks. cya Thursday.
• Thanks! See you Thursday
• Thank you
• cheers
• bbye
• Thank you!

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Wiki

Link to the UR Courses wiki page for this meeting