Python

Question 1

+

Answer 1

Addition

Question 2

-

Answer 2

Subtraction

Question 3

*

Answer 3

Multiplication

Question 4

/

Answer 4

Division (standard); floating-point numbers

Question 5

//

Answer 5

Division (integer); no decimals; rounds to whole num

Question 6

**

Answer 6

Exponents

Question 7

“Hi” + “ world!”

Answer 7

Text in quotes added together

Question 8

“Hi” * 5

Answer 8

Concatenates copies of the string

Question 9

[1,2] + [3,4]

Answer 9

Concatenates the lists into one list
Python is 0-indexed, so [1] is list item 0

Question 10

not True

Answer 10

Negation

Question 11

True or False

Answer 11

One OR the other must be True statements

Question 12

True and False

Answer 12

Both must be true to be true

Question 13

==

Answer 13

Equals to

Question 14

!=

Answer 14

Not equal to

Question 15

<

Answer 15

Less than

Question 16

>

Answer 16

Greater than

Question 17

<=

Answer 17

Less than or equal to

Question 18

> =

Answer 18

Greater than or equal to

Question 19

And

Answer 19

Both conditions must be true

Question 20

Or

Answer 20

One condition must be true

Question 21

if statements

Answer 21

conditional statement with the options if, else, elif

Question 22

elif

Answer 22

elif (else if) = multiple conditions with different responses

Question 23

name = “Averil”
if name == “Averil”:
response = “Hi Averil!”
else:
response = “Girl bye.”

Answer 23

Hi Averil!

Question 24

name = “Averil”
if name == “Averil”:
response = “Hi Averil!”
elif name = “Ava”:
response = “Hi Ava”
else:
response = “Girl bye.”

Answer 24

Hi Averil!

Question 25

ways to use Python

Answer 25

1. From command-line prompt (run directly from prompts) 2. As a script 3. In a browser (Jupyter, Google Colab) -- Use mouse to edit texts -- Groups commands in same cell ***accessible across many platforms for all users

Question 26

Why Python in comp bio?

Answer 26

Massive scientific community Tests/writes code quickly Easy to learn and use Compiles scientific libraries (ex/ numpy) VERSATILE

Question 27

expressions

Answer 27

Python expressions simply calculations and text manipulations

Question 28

variables

Answer 28

- provide flexible storage for diverse data types - can be put in variables (lists, numbers, strings, etc) Variable name criteria: -- One word only -- Numbers, letters, _ only -- Cannot begin with a number -- Case sensitive

Question 29

flow control structures

Answer 29

Flow control structures guide Python’s decision-making -- if, elif, else statements

Question 30

dictionaries

Answer 30

- Map keys to values for efficient data retrieval - Unordered mapping of a key (string, num) to a value (string, num, etc)

Question 31

d = { } d["key"] = "value" d["key2"] = 5 d["key3"] = {"h":"I"} print(d["key2"])

Answer 31

5

Question 32

lists

Answer 32

Lists store ordered data for sequential processing (doesn’t have to be the same data type)

Question 33

d = [“hello”, 5] print (d)

Answer 33

“hello”, 5

Question 34

d = [] d.append[5] d.append[6] d.append[7] print (d[1])

Answer 34

6 Creates an empty lists and then adds items to the 0-indexed list

Question 35

for loops

Answer 35

For loops allow you to go through a list item by item (iterates through lists/sequences)

Question 36

for i in [1,2,3]: print (i*i)

Answer 36

1 2 3

Question 37

for x in [“dog”, “cat”]: print (x)

Answer 37

dog cat

Question 38

definitions

Answer 38

Python functions or definitions organize reusable blocks of code def → defines a function return → determines the output

Question 39

def add_numbers(a,b): return a + b add_numbers(5,6)

Answer 39

12

Question 40

def add_nums_and_double(c,d): var1 = c+d var2 = 2 * var1 return var2 add_nums_and_double(5,7)

Answer 40

24

Question 41

def name_person(name): return name + “ is fun!” name_person(“Averil”)

Answer 41

Averil is fun!

Question 42

Libraries

Answer 42

- Extend Python capabilities Through pre-written code that can be used in your own program Ex/ Numpy: advanced math features (arrays + vectorization)

Question 43

import numpy a = numpy.array([[1,2,3], [4,5,6], [7,8,9]]) a*5

Answer 43

array ([[5,10,15], [20,25,30], [35,40,45]])

Question 44

Python Common Errors

Answer 44

Definition MUST PRECEDE usage Consistent indentation is necessary == indicates equality = assigns a variable Mix only compatible variable types Remember to add return to a definition to produce an output

Question 45

student = { "name": "Alice", "age": 20, "major": "Computer Science" } print(student["name"]) print(student["age"]) student["gpa"] = 3.8 Iterating through the dictionary for key, value in student.items(): print(key, ":", value)

Answer 45

Alice 20 name : Alice age : 20 major : Computer Science gpa : 3.8