Difference between revisions of "EGR 103/Concept List Fall 2019"

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* Question in class: does Python have ++ or -- operators; it does not.  You need x += 1 or x -= 1
 
* Question in class: does Python have ++ or -- operators; it does not.  You need x += 1 or x -= 1
===Lecture 6 ===
+
===Lecture 7 ===
* Things that do not change memory address of a list:
+
* Distinction between == and i
 +
* Iterable types and how they work (list, tuple, string
 +
* Things that do not change memory address of a list (and therefore change what a loop iterates over):
 
** +, .append(), .extend(), .insert(), .remove(), .pop(), .sort(), .reverse(), .clear()
 
** +, .append(), .extend(), .insert(), .remove(), .pop(), .sort(), .reverse(), .clear()
 
* Things that do change memory address of a list:
 
* Things that do change memory address of a list:
** Total replacement, replacement by self-slice
+
** Total replacement, replacement by self-slice, making a copy
* Making a list from arbitrary items in a list (i.e. non-sliceable)
+
* Singularity functions
[vals[k] for k in (3, 1, 4, 1)]
+
** Unit step <math>u(t)</math>
 +
** See [[Singularity Functions]] for way too much information - more in lab!
  
  

Revision as of 20:45, 17 September 2018

This page will be used to keep track of the commands and major concepts for each lab in EGR 103.

Lectures

Lecture 1 - Introduction

  • Class web page: EGR 103L; assignments, contact info, readings, etc - see slides on Errata/Notes page
  • Sakai page: Sakai 103L page; grades, surveys and tests, some assignment submissions
  • Piazza page: Piazza 103L page; message board for questions

Lecture 2 - Programs and Programming

  • To play with Python:
    • Install it on your machine or a public machine: Download
    • Use a Duke container with Spyder: Containers - note - these do not have access to your Duke files. More on how to connect that later.
  • Quick tour of Python
    • Editing window, variable explorer, and console
    • Variable explorer is your friend
  • From Dewey - programming language typically have ability to work with input, output, math, conditional execution, and repetition
  • Hilton and Bracy Seven Steps
  • Class work developing algorithm for program to determine if a number is prime

Lecture 3

  • 7 Steps for finding prime numbers
  • prime program -- includes intro to input(), if tree, for loop, print(), remainder %

Lecture 4

  • Function definitions
    • Positional and key word arguments (kwargs)
    • Default values
    • Returns tuples -- can be received by a single item or a tuple of the right size
  • Aquarium

Lecture 5

  • print() and format specifications: link
    • Main components are width, precision, and type; sometimes initial +
    • e and f can print integers as floats; d cannot print floats
  • relational and logical operators - how they work on item, string, list, tuple
  • if trees
  • while loops
  • for loops
    • NOTE: in the case of
for y in x
If the entries of x are changed, or really if x is changed in a way that its location in memory remained unchanged, y will iterate over the changed entries. If x is changed so that a copy first has to be made (for example, it is set equal to a slice of itself), then y will iterate over the original entries. Note the differences between:
x = [1, 2, 3, 4, 5]
for y in x:
    print(x, y)
    x[4] = [0]
    print(x, y)

and:

x = [1, 2, 3, 4, 5]
for y in x:
    print(x, y)
    x = x[:-1]
    print(x, y)
  • counting characters program
# letter_typing.py from class:
def check_letters(phrase):
    vowels = "aeiou"
    numbers = "0123456789"
    consonants = "bcdfghjklmnpqrstvwxyz"
    # vowels, numbers, consonants, and other in that order
    count = [0, 0, 0, 0]
    
    for letter in phrase:
        if letter.lower() in vowels:
            count[0] += 1
        elif letter.lower() in numbers: # .lower not really needed here
            count[1] += 1
        elif letter.lower() in consonants:
            count[2] += 1
        else:
            count[3] += 1
            
    return count

out = check_letters("Let's go Duke University 2018!")
print(out)
  • Question in class: does Python have ++ or -- operators; it does not. You need x += 1 or x -= 1

Lecture 7

  • Distinction between == and i
  • Iterable types and how they work (list, tuple, string
  • Things that do not change memory address of a list (and therefore change what a loop iterates over):
    • +, .append(), .extend(), .insert(), .remove(), .pop(), .sort(), .reverse(), .clear()
  • Things that do change memory address of a list:
    • Total replacement, replacement by self-slice, making a copy
  • Singularity functions


Labs

  • Lab 1
    • Unix commands: pwd, cd, ls, mkdir, wget, tar, cp, latex, dvipdf, evince, xeyes
    • Other concepts: MobaXterm, XQuartz, ssh
    • Windows permissions were covered, but were only needed during this one lab.
    • Mounting CIFS drives was covered, but will not be needed for lab 1.
    • Three parts of lab:
      • Once only ever: creating EGR 103 folder, setting Windows permissions
      • Once per lab: creating lab1 folder, wget-ting files, tar expansion, duplicate lab skeleton
      • Doing work: changing to lab1 folder; using emacs, latex, dvipsd, and evince correctly
    • Work on lab every day - at least logging in, changing directories, using (emacs, latex, dvipdf, evince)
    • Work a little at a time to help with debugging