Index

Book

Latest version of “Metaphors Be With You …”

Course

This is the Winter 2020 version of Discrete Mathematics I — AKA DM1 — AKA CS 237. Compare this with your version, which as of Spring 2020 has been renamed CSE 280.

Syllabus

PDF Version

Schedule

(This is reproduced from the syllabus.)

Reading the book is a regular activity you are tasked with. There are three main sections and essentially three months (12 full weeks) in the semester. That’s one main section per month, or about one subsection every week. You are welcome to read ahead and work exercises/problems/puzzles at your own pace, but don’t get behind!

More details will be available in each week’s course files, but here’s an outline:

Week	Reading	Exercises/Problems/Puzzles (EPPs)
01	<ABC	CRC DGZ CHJ DOK CJF DZB
02	ABC	OQP USV UCA ODS UGX OGR UWM OPZ UOX OTX
		UOT OIM UIN OJL UCG OIO UIJ OQT UTQ OYU
		UOH OZD UZM OOY UFZ OKJ UVH OJM ULQ OTD
		UJU OLH UWY OBW USL OYP UBV OKQ UKF OKL
		UEZ OYW UEF OUB UQY
03	DEF	TDR WDT TEH WFC TEJ WFK TER WGP TEU WJS
		TGE WKC THP WKM TIW WNW TKG WOV TME WQW
		TMZ WRA TNL WRD TNQ WRP TOJ WRU TOL WZO
		TOU TLI WPI TTV WUZ TUK WVQ TUQ WVU TUW
		TVL WWS TXG TKH WUE
04	GHI	EBQ MGX ECI MHB ECT MKJ EFE MKL EFS MLB
		EJE MLU EJK MMC EJU MNE EKQ MON
05	JKL	QAM REX QCV RFC QCZ RFF QDM RGL QEB RGM
		QFK RHB QGK RVB QGT RJV QIQ RLH QKA RNC
		QKT RNM QOS ROP QRQ ROX
06	MNO	FAB ISM FBH ITT FDK IVO FDZ IWC FJH IWK
		FJY IXT FMD IYJ FOJ IZL FOY VAO FQI VAR
		FQL VAY FQW VCR FRM VEM FUA VFJ FVF VGU
		FVH VGX FXI VIB FYR VIW
07	PQR	GMQ JPZ GMY JQA GRZ JYA GXF XAJ GYI XFO
08		GYN XGG
09	STU	LDA SQI LJP SUF LNR YGT LDO YCF LUM YZU
10		LTI YDQ LND YTR LGO YIV
11	VWX	HST KDB HTC KPS ABR KWD HRR KEO HMO HIJ
12		KLE HAB KOV HBT AGA KNF HJS HAX KHQ HKE
		KBB HRL AGD HSG KHO ANA HLX KSI HTR KSQ
		HBE KSC
13	YZ@	BAO NCO PDQ NTC PTW NTM PMV NES BRZ BRE
		NGP BRQ PIQ PRK NIO PFA BGT NGI NLR BSP
		NBO PBI BJO NKY BMI

Tools

Regarding tools in general, here’s a thought by Howard Rheingold from his book, They Have A Word For It:

If you examine the beliefs of any master craftsman, you will discover a certain reverence for tools as worthy friends. The world-renowned Japanese temple carpenters, for example, spend much more time sharpening a tool than they spend making the cuts. The spirit of fine Japanese carpentry dictates that the planning and contemplation of a construction project should take much longer than the execution; in some cases, the carpenter lives on the site of a house or temple for at least a year, paying attention to the geography and the light, sharpening his tools, visualizing each cut, each piece of joinery, in his head, over and over again.

Any Computer Professional, no matter what specialty area he or she focuses on (science, engineering, technology, math), needs a good set of tools. The two main tool platforms are Windows and Mac. If you prefer Linux (or some other similar platform), you probably do not need any help provisioning your professional toolbox. Otherwise, select your preference and read on. Note that the tools you will need are few, but powerful! Note too that you must have a steady, reliable Internet connection (use the BYUI WiFi, not BYUI Visitor) to be successful.

Windows

64-bit only. If you do not have 64-bit Windows, please get it!

Git

Watch Video on How to Install Git for Windows (older version).

[ ] Install (latest version) Git for Windows:
https://github.com/git-for-windows/git/releases/download/v2.26.2.windows.1/Git-2.26.2-64-bit.exe — or less directly, if you want to have a fuller experience, start at: https://git-for-windows.github.io
[ ] Run the installer and click Next five times to accept the defaults, pausing before the sixth Next to change the default on Adjusting the PATH Environment to be the third choice (Use Git and optional Unix tools from the Command Prompt). Now click Next five more times, again accepting all the defaults, and then click Install. Once it is finished, first uncheck View Release Notes, then click Finish.
[ ] Bring up the Windows Command Shell (AKA Command Prompt, the cmd.exe program) by pressing the “Windows” key (the one with the Windows logo on it) and, while holding that key down, typing R to open the Run dialog and entering cmd.
[ ] Check that you have installed this tool correctly by entering the following command:

git

[ ] Make sure you see output that looks like usage instructions for the “git” command, and NOT an error message like

'git' is not recognized as an internal or external command ...

[ ] Leave this Command window open, as you will need it for entering the next command (see below).

Emacs

Watch Video on How to Install Emacs and One on How to Setup the Emacs Daemon.

Set HOME Environment Variable

[ ] Enter the following command in the new Command window:

setx HOME "%USERPROFILE%"

[ ] Close this Command window and open a new one.
[ ] Now enter the following command, and make sure it prints out the directory you were connected to when you first opened a Command window (which usually is something like C:\Users\uname where uname is your user name).

echo %HOME%

[ ] Keep this Command window open, as you will need it for the Spacemacs installation steps (below).

Download and Install

Get the installer for the latest version (26.3) here:

https://github.com/arbv/emacs-msi-installer/releases/download/v26.3-per-user/emacs-26.3-x86_64.msi Run this wizard and accept all the defaults for the easiest installation.

For ease of use, the built-in shortcut functionality of Windows enables the automatic startup of a Daemon on boot, and the creation of a Client that will either connect to that Daemon, or start a new instance if no Daemon is running. Daemon essentially means Server in this context.

IMPORTANT: The following assumes you chose the

C:\Program Files\GNU Emacs

default location when installing Emacs. If you chose some other location, change the paths below accordingly.

Create Daemon

[ ] Step 1: Create a shortcut named Emacs Daemon with the following target:

"C:\Program Files\GNU Emacs\bin\runemacs.exe" --daemon

[ ] Step 2: Copy the shortcut to the Start Menu

C:\Users\[USERNAME]\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\

[ ] Step 3 [Optional]: To start at boot, create a copy of the shortcut in the Startup folder:

C:\Users\[USERNAME]\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Startup

Create Client

[ ] Step 1: Create a shortcut just named Emacs with the following target:

"C:\Program Files\GNU Emacs\bin\emacsclientw.exe" -n -a "" -c

This shortcut first tries to connect using emacsclient and if that fails, it falls back to runemacs.

[ ] Step 2: Copy the shortcut to the Start Menu:

C:\Users\[USERNAME]\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\

This is your primary shortcut for interacting with Emacs. Pin this one (not the other) to the Start Menu, and the Taskbar.

Configure File Explorer

Now tell Windows to open all .txt files (for example) with Emacs by default, and do so by connecting to the Emacs Daemon (or starting a new instance if no Daemon is running).

[ ] Step 1: Right-click on a file of the type you want Emacs to open.
[ ] Step 2: Either choose “Open with..” or hover over it and pick “Choose another app”.
[ ] Step 3: Ignore all the options for “How do you want to open this file?” and choose “More apps”.
[ ] Step 4: This is the crucial step! “Look for another app on this PC” but do NOT find the .exe for Emacs — instead find the Emacs shortcut in your Start Menu, and use that.
[ ] Step 5: Check the box “Always use this app to open .txt (or whatever) files”.
[ ] Hereafter: when you open the file by clicking on it Windows will do so using this shortcut, which makes it work as expected.

Spacemacs

Watch Video on How to Install and Configure and Initialize Spacemacs

[ ] Enter the following command in the Command window, which you should have left opened (if not, see above for how to bring it back):

git clone https://github.com/syl20bnr/spacemacs .emacs.d

Save typing by copying it to your clipboard from the box above, and then pasting it:

Beware that if you copy this from the Spacemacs home page (after pressing the “Install” button) there is a subtle difference that can trip you up. Before hitting Enter be sure to back up and remove the ~/ in front of the .emacs.d so that the command looks like the one above.

[ ] Enter the correct command, and then be patient, as it will take a few seconds to clone this large repository to your computer.
[ ] You will get an error if the .emacs.d directory already existed and had something in it, the reason being that git will only clone into an existing directory if it is empty. Move or rename it, or if there is nothing important in that directory, the following command will remove it:

rmdir /s /q .emacs.d

[ ] Run the git clone command again if necessary.
[ ] Now to configure Spacemacs, enter this command in the same Command window:

git clone https://github.com/rickneff/firstthreeodds .spacemacs.d

[ ] Start up Emacs (use your shortcut) and the Spacemacs installation process will begin.
[ ] Again, be patient, it’s downloading and installing dozens of plugins (called packages in Emacs-land).
[ ] While you’re waiting, visit the Spacemacs home page and browse around: http://www.spacemacs.org
[ ] If it looks like something went wrong, restart Emacs. Sometimes, network glitches cause some packages to be incompletely downloaded, but this is easily recoverable by restarting.
[ ] Watch VIM Quickstart Video.
[ ] Watch Spacemacs Quickstart Video.

Mac

Watch Video on Installing Tools on a Mac.

Homebrew

As stated at the Homebrew website, this is the “missing” package manager for macOS. With it, you can easily install git (and other Xcode command-line tools), emacs, all their dependencies, and more.

[ ] Type Command Space to bring up the Spotlight Search box and enter terminal to open a Terminal window.
[ ] Enter this command in the Terminal window to install Homebrew:

/usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"

Emacs

[ ] Enter these two “brew” commands in your Terminal window:

brew tap d12frosted/Emacs-plus
brew install emacs-plus

[ ] You have installed Emacs — but DO NOT RUN IT YET!
[ ] Verify that your terminal output looks something like this saved output from when I installed emacs on my Macbook.

Spacemacs

[ ] Open or select a Terminal window.
[ ] Enter the following command in the Terminal window. Save typing by copying it to your clipboard from the box below or from the Spacemacs home page, as shown in the following screenshot.

git clone https://github.com/syl20bnr/spacemacs ~/.emacs.d

[ ] Be patient, it will take a few seconds to clone this large repository to your computer.
[ ] Now to configure Spacemacs, enter this command in the same Terminal window:

git clone https://github.com/rickneff/firstthreeodds ~/.spacemacs.d

[ ] Enter in your Terminal window:

emacs&

This will start up Emacs, and then the Spacemacs installation process will automatically begin.

[ ] Again, be patient, it’s downloading and installing dozens of plugins (called packages in Emacs-land).
[ ] While you’re waiting, visit the Spacemacs home page and browse around: http://www.spacemacs.org
[ ] If it looks like something went wrong, restart Emacs. Sometimes, network glitches cause some packages to be incompletely downloaded, but this is easily recoverable by restarting.
[ ] Watch VIM Quickstart Video.
[ ] Watch Spacemacs Quickstart Video. (This is on Windows, but Spacemacs works on Mac the same.)

Helps

TODO Read the FAQs

Frequently Asked Questions (and their Answers):

Q1

Why can’t I view the CSE 280 course on I-Learn?

A1

This course is not published on I-Learn until the first day of class.

Q2

The workload for this 2-credit class seems excessive. What should I do?

A2

Ponder the reasons you are taking this class. Are you striving to learn discrete math? Just here for the grade? Do you see yourself as a good reader, with good reading comprehension skills? A pitfall some of you will encounter is attempting the Exercises/Problems/Puzzles (EPPs for short) without good comprehension of the concepts you are asked to explore by way of these EPPs. Many exercises should take a few seconds, or a few minutes, maybe up to an hour or more for some of the problems (OQP for example) — if you are grasping what you are reading! If you read a sentence or a paragraph or a section, and then think to yourself, I have no idea what what I just read means — that’s a different kind of problem. Reading and understanding take time — is the time you spend doing this productive?

Q3

Okay, so I’m not the most skilled reader. It takes me a long time to read and digest things, especially when there are so many links to other things to read (and from them to still others). What do I do, settle for a poor grade? Drop the class?

A3

You are responsible for your learning. I as your teacher take seriously my role as and responsibility for being a helper, a facilitator of your learning — but I can’t make it happen. You can compensate for not (yet) being a skilled reader and problem solver, however.

Q4

How?

A4

Be inquisitive. Be very inquisitive! Ask questions, not just of me, but of your classmates. Share light and knowledge you gain on your own (or through talking with me or my TAs) freely, and appropriately with your peers!

Q5

Are we required to study in groups? I’m not a big fan of group work/think.

A5

What does the BYU-I Learning Model say about “Teach One Another”? Are you a non-fan because of past experience, where you were let down by members of your group? Were you assigned this group, or was it self-selected?

Q6

Yes, and it was assigned. Are you suggesting I should choose my own group to study with?

A6

Yes, most assuredly and emphatically YES!

Q7

What do you mean by appropriately sharing with my peers?

A7

Good sharing and collaboration is a “me lift thee and thee lift me, and we both ascend together” phenomenon. Bad sharing/collaboration is copying someone else’s work and submitting it as your own, to get “credit” for doing some assigned task, while not getting the understanding doing the task was meant to give you.

Q8

Are there any tutors for this class?

A8

Yes, but not through the Tutoring Center. They double as my TAs, and these links are to videos you can watch to be introduced to:

TODO Glean What You Can From Guides and Cheat Sheets For Beginners

https://ontologicalblog.com/2016/10/14/an-absolute-beginners-guide-to-spacemacs-for-academic-writing/

https://ontologicalblog.files.wordpress.com/2016/12/spacemacs_cheat_sheet_1-22.pdf

https://simpletutorials.com/c/3036/Spacemacs+%28Vim+mode%29+Cheatsheet

http://www.pavley.com/2015/09/01/lisp-cons-cell-and-list-cheat-sheet/

TODO Convince Yourself that Learning a Little Lisp is Worthwhile

Read this blog post by Mark Miller, and then be sure to read the article he links to in his first sentence (link preserved here):

This is the best introductory, conceptual article on Lisp I’ve ever seen. It’s written by Slava Akhmechet.