Difference between revisions of "EGR 103/Concept List Fall 2019"
Jump to navigation
Jump to search
(→Lecture 7 - Applications) |
(→Lecture 7 - Applications) |
||
Line 143: | Line 143: | ||
print('LOOOOOOOOOOOOOOOSER') | print('LOOOOOOOOOOOOOOOSER') | ||
+ | </source> | ||
+ | </div> | ||
+ | </div> | ||
+ | |||
+ | * NATO Phonetic Translator - [https://en.wikipedia.org/wiki/NATO_phonetic_alphabet NATO phonetic alphabet] | ||
+ | <div class="mw-collapsible mw-collapsed"> | ||
+ | <source lang=python> | ||
+ | # nato_trans.py from class: | ||
+ | </source> | ||
+ | <div class="mw-collapsible-content"> | ||
+ | <source lang=python> | ||
+ | fread = open('NATO.dat', 'r') | ||
+ | |||
+ | d = {} | ||
+ | |||
+ | for puppies in fread: | ||
+ | #print(puppies) $ if you want to see the whole line | ||
+ | |||
+ | #key = puppies[0] | ||
+ | #value = puppies[:-1] | ||
+ | #d[key] = value | ||
+ | |||
+ | d[puppies[0]] = puppies[:-1] | ||
+ | |||
+ | fread.close() | ||
+ | |||
+ | hamster = input('Word: ').upper() | ||
+ | |||
+ | for kittens in hamster: | ||
+ | #print(d[letter], end=' ') | ||
+ | print(d.get(kittens, 'XXX'), end=' ') | ||
+ | |||
+ | ''' | ||
+ | In class - one question was "in cases where there is not a code, can it | ||
+ | return the original value instead of XXX" -- yes: | ||
+ | print(d.get(kittens, kittens)) | ||
+ | ''' | ||
+ | </source> | ||
+ | </div> | ||
+ | </div> | ||
+ | :* Data file we used: | ||
+ | <div class="mw-collapsible mw-collapsed"> | ||
+ | <source lang=python> | ||
+ | # NATO.dat from class: | ||
+ | </source> | ||
+ | <div class="mw-collapsible-content"> | ||
+ | <source lang=python> | ||
+ | Alfa | ||
+ | Bravo | ||
+ | Charlie | ||
+ | Delta | ||
+ | Echo | ||
+ | Foxtrot | ||
+ | Golf | ||
+ | Hotel | ||
+ | India | ||
+ | Juliett | ||
+ | Kilo | ||
+ | Lima | ||
+ | Mike | ||
+ | November | ||
+ | Oscar | ||
+ | Papa | ||
+ | Quebec | ||
+ | Romeo | ||
+ | Sierra | ||
+ | Tango | ||
+ | Uniform | ||
+ | Victor | ||
+ | Whiskey | ||
+ | X-ray | ||
+ | Yankee | ||
+ | Zulu | ||
+ | |||
</source> | </source> | ||
</div> | </div> |
Revision as of 02:39, 17 September 2019
This page will be used to keep track of the commands and major concepts for each lecture in EGR 103.
Contents
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
- CampusWire page: CampusWire 103L page; message board for questions - you need to be in the class and have the access code to subscribe.
Lecture 2 - Programs and Programming
- Seven steps of programming -
- Watch video on Developing an Algorithm
- Watch video on A Seven Step Approach to Solving Programming Problems
- To play with Python:
- Install it on your machine or a public machine: Download
- Quick tour of Python
- Editing window, variable explorer, and console
- You are not expected to remember any of the specifics about how Python stores things or works with them yet!
Lecture 3 - "Number" Types
- Python is a "typed" language - variables have types
- We will use eight types:
- Focus of the day: int, float, and array
- Focus a little later: string, list, tuple
- Focus later: dictionary, set
- int: integers; Python can store these perfectly
- float: floating point numbers - "numbers with decimal points" - Python sometimes has problems
- array
- Requires numpy, usually with
import numpy as np
- Organizational unit for storing rectangular arrays of numbers
- Requires numpy, usually with
- Math with "Number" types works the way you expect
- ** * / // % + -
- Relational operators can compare "Number" Types and work the way you expect with True or False as an answer
- < <= == >= > !=
- With arrays, either same size or one is a single value; result will be an array of True and False the same size as the array
- Slices allow us to extract information from an array or put information into an array
- a[0] is the element in a at the start
- a[3] is the element in a three away from the start
- a[:] is all the elements in a because what is really happening is:
- a[start:until] where start is the first index and until is just *past* the last index;
- a[3:7] will return a[3] through a[6] in 4-element array
- a[start:until:increment] will skip indices by increment instead of 1
- To go backwards, a[start:until:-increment] will start at an index and then go backwards until getting at or just past until.
- For 2-D arrays, you can index items with either separate row and column indices or indices separated by commas:
- a[2][3] is the same as a[2, 3]
- Only works for arrays!
Lecture 4 - Other Types and Functions
- Lists are set off with [ ] and entries can be any valid type (including other lists!); entries can be of different types from other entries
- List items can be changed
- Tuples are indicated by commas without square brackets (and are usually shown with parentheses - which are required if trying to make a tuple an entry in a tuple or a list)
- Dictionaries are collections of key : value pairs set off with { }; keys can be any immutable type (int, float, string, tuple) and must be unique; values can be any type and do not need to be unique
- To read more:
- Note! Many of the tutorials below use Python 2 so instead of
print(thing)
it showsprint thing
- Lists at tutorialspoint
- Tuples at tutorialspoint
- Dictionary at tutorialspoint
- Note! Many of the tutorials below use Python 2 so instead of
- Defined functions can be multiple lines of code and have multiple outputs.
- Four different types of input parameters:
- Required (listed first)
- Named with defaults (second)
- Additional positional arguments ("*args") (third)
- Function will create a tuple containing these items in order
- Additional keyword arguments ("**kwargs") (last)
- Function will create a dictionary of keyword and value pairs
- Function ends when indentation stops or when the function hits a return statement
- Return returns single item as an item of that type; if there are multiple items returned, they are stored in a tuple
- If there is a left side to the function call, it either needs to be a single variable name or a tuple with as many entries as the number of items returned
- Four different types of input parameters:
Lecture 5 - Format, Logic, Decisions, and Loops
- Creating formatted strings using {} and .format() (format strings, standard format specifiers) -- focus was on using e or f for type, minimumwidth.precision, and possibly a + in front to force printing + for positive numbers.
- Also - Format Specification Mini-Language
- Basics of decisions using if...elif...else
- Building a program to check for vowels, consonants, and y
- Bonus material:
- Rhabarberbarbara - now with subtitles!
- Rhabarberbarbara - live recording!
- Lion-Eating Poet in the Stone Den - 施氏食獅史, or Shī Shì shí shī shǐ
- Buffalo$$^8$$
Lecture 6 - String Things and Loops
ord
to get numerical value of each characterchr
to get character based on integermap(fun, sequence)
to apply a function to each item in a sequence- Basics of while loops
- Basics of for loops
- List comprehensions
- [FUNCTION for VAR in SEQUENCE if LOGIC]
- The FUNCTION should return a single thing (though that thing can be a list, tuple, etc)
- The "if LOGIC" part is optional
[k for k in range(3)]
creates[0, 1, 2]
[k**2 for k in range (5, 8)]
creates[25, 36, 49]
[k for k in 'hello' if k<'i']
creates['h', 'e']
[(k,k**2) for k in range(11) if k%3==2]
creates[(2, 4), (5, 25), (8, 64)]
- [FUNCTION for VAR in SEQUENCE if LOGIC]
-
- Wait - that's the simplified version...here:
- Wait - that's the simplified version...here:
- Want to see Amharic?
list(map(chr, range(4608, 4992)))
- Want to see the Greek alphabet?
for k in range(913,913+25):
print(chr(k), chr(k+32))
Lecture 7 - Applications
- The Price Is Right - Clock Game video demonstration
# tpir.py from class:
import numpy as np
import time
def create_price(low=100, high=1500):
return np.random.randint(low, high+1)
def get_guess():
guess = int(input('Guess: '))
return guess
def check_guess(actual, guess):
if actual > guess:
print('Higher!')
elif actual < guess:
print('Lower!')
if __name__ == '__main__':
#print(create_price(0, 100))
the_price = create_price()
the_guess = get_guess()
start_time = time.clock()
#print(the_guess)
while the_price != the_guess and (time.clock() < start_time+30):
check_guess(the_price, the_guess)
the_guess = get_guess()
if the_price==the_guess:
print('You win!!!!!!!')
else:
print('LOOOOOOOOOOOOOOOSER')
- NATO Phonetic Translator - NATO phonetic alphabet
# nato_trans.py from class:
fread = open('NATO.dat', 'r')
d = {}
for puppies in fread:
#print(puppies) $ if you want to see the whole line
#key = puppies[0]
#value = puppies[:-1]
#d[key] = value
d[puppies[0]] = puppies[:-1]
fread.close()
hamster = input('Word: ').upper()
for kittens in hamster:
#print(d[letter], end=' ')
print(d.get(kittens, 'XXX'), end=' ')
'''
In class - one question was "in cases where there is not a code, can it
return the original value instead of XXX" -- yes:
print(d.get(kittens, kittens))
'''
- Data file we used:
# NATO.dat from class:
Alfa
Bravo
Charlie
Delta
Echo
Foxtrot
Golf
Hotel
India
Juliett
Kilo
Lima
Mike
November
Oscar
Papa
Quebec
Romeo
Sierra
Tango
Uniform
Victor
Whiskey
X-ray
Yankee
Zulu