Python

Question 1

Python3 features

Answer 1

Free and open sources
Object oriented Language
Portable- use on Mac, Linux, Unix
Interpreted Language- executed line by line bot compled
Dynamically typed - No need to declare var types
Automatic memory management
built-in data structures
Functions are first class objects that make difficult tasks simple

Question 2

Python Memory Management

Answer 2

Memory management in Python involves a private heap containing all Python objects and data structures. The management of this private heap is ensured internally by the Python memory manager. The Python memory manager has different components which deal with various dynamic storage management aspects, like sharing, segmentation, preallocation or caching.

Question 3

Error handeling

Answer 3

Try:
this block of code
Except:
do this if you hit an error

Question 4

Lists

Answer 4

Mutable
Ordered collection of items
Can store any sort of object
some functions you can do: Slice, delete, insert, pop, reverse
Lists are great to use when you want to work with many related values. They enable you to keep data together that belongs together, condense your code, and perform the same methods and operations on multiple values at once
Opt for a list when you need an ordered sequence of items

Question 5

Dictionary

Answer 5

Do you need to associate values with keys, so you can look them up efficiently (by key) later on? Use a dictionary.
Mutable
Unordered
Unique keys

Question 6

Tuple

Answer 6

Immutable
Ordered
When you want to collect an immutable ordered list of elements, use a tuple. (For example, when you want a (name, phone_number) pair that you wish to use as an element in a set, you would need a tuple rather than a list since sets require elements be immutable).

Question 7

Sets

Answer 7

Unordered
Distinct
Commonly used to remove dupes
mutable
When you want an unordered collection of unique elements, use a set. (For example, when you want the set of all the words used in a document).

Question 8

algorithim

Answer 8

A set of specific steps for solving a category of problems

Question 9

high level language

Answer 9

A programming language like Python that is designed to be easy for humans to read and write.

Question 10

list comprehensions

Answer 10

Best to use when you need to create a new list from other iterables

Question 11

For loop

Answer 11

Used to iterate through elements of an array or a list

Question 12

While loop

Answer 12

Perform and indefinite number of iterations as long as a condition remains true

Question 13

NumPy

Answer 13

one of the principal packages for data science applications
often used to process large multidimensional arrays, extensive collections of high-level mathematical functions and matrices
Implementation methods make it easy to conduct multiple operations with these objects

Question 14

Pandas

Answer 14

Python is a powerful tool for data analytics which comes with a variety of built-in methods for combining, filtering, and grouping data.

Question 15

Modules

Answer 15

Files containing Python code, can be functions, classes, or variables. Some common built-in modules are
os
sys
math
random

Question 16

Global variables

Answer 16

Variables declared outside a function or in global space are global variables. Can be accessed by any function in the program

Question 17

local variables

Answer 17

declared inside a functions and can only be accessed within

Question 18

Init

Answer 18

init is a method or constructor in Python that is automatically called to allocate memory when a new object/instance of a class is created

Question 19

lambda

Answer 19

an anonymous function can have any number of parameters bu just one statement

Question 20

Break

Answer 20

allows loop termination when some condition is met and the control is transferred to the next statement

Question 21

Continue

Answer 21

Allows skipping some part of loop when some specific condition is met and the control is transferred to the beginning of the loop

Question 22

Combine objects method

Answer 22

zip(list1,list2)

combined_zip)list = [*combined_zip]

Question 23

Create a dict counting how many times a value in a list appears in that list

Answer 23

from collections import Counter

type_counts = Counter(list)

Question 24

how to make combinations

Answer 24

from itertools import combinations

combo = list(combinations(list to combine, values per combo)

Question 25

Set methods

Answer 25

comparing two sets
intersection: all elements that are in both sets
ex) set_a.intersection(set_b)
difference: all elements in one set but not the other
symmetric_difference(): all elements in exactly one set
union(): all elements that are in either set

Question 26

numpy methods

Answer 26

np. mean(list, axis (1 will be row based 0will be column)
np. sum(list, axis if you want)
np. subtract(array1, array2)

Question 27

method that creates a list of numbers

Answer 27

range(start, stop (will not include this number), step)

Question 28

index, values of a list method

Answer 28

enumerate(list, start=start index)

Question 29

apply a function to each element in a list

Answer 29

map(function to use, list)
ex) 
def addition(n):
n+n
numbers = (1,2,3,5)
output of list(map(addition,numbers))
[2,4,6,10]