Just general python data science stuff

Question 1

how to iterate over dictionary key-values pairs?

Answer 1

for key, value in dictionary.items():

print(key, “ - “, value)

Question 2

create a np array of all the numbers from 0 to 20

Answer 2

array = np.arange(21)

Question 3

create a 2d numpy array; all numbers from 0 to 20 in 4 rows of data

Answer 3

array = np.arange(20). reshape(4,5)

Question 4

check the shape of a np array “array”

Answer 4

array.shape

Question 5

create a np array of the numbers between 50 and 100, increasing in intervals of 5

Answer 5

array = np.arange(50, 101, 5)

Question 6

create a np array consisting of all zeros, let’s say with 5 rows of 7 items each.

Answer 6

array = np.zeros((5,7))

Question 7

create a np array consisting of all ones, let’s say with 4 rows of 2 items each.

Answer 7

array = np.ones((4,2))

Question 8

create a numpy array full of threes, 10 rows of 3 items

Answer 8

array = np.full((10,3),3)

Question 9

create a numpy array with 4 numbers, equally spaced between (and including) 0 and 1.

Answer 9

array = np.linspace(0,1, num = 4)

Question 10

create a numpy array by straight up typing a list of numbers

Answer 10

array = np.array([0,1,2,3,4,5])

Question 11

iterate over all the items in a multi-dimensional numpy array, and - whatever - prints it

Answer 11

for item in np.ndinter(array):

print(item)

Question 12

transpose a numpy array

Answer 12

npArrayTransposed = np.transpose(npArray)