Python

Front 1

len( )

Back 1

give the length of a list.

Front 2

max( )

Back 2

Gives the maximum value of a list.

Front 3

abs( )

Back 3

give the absolute value of a number.

Front 4

pow(x, y[z,])

Back 4

It gives x**y with two arguments, the optional third arg is equivalent to (x**y)%z.

Front 5

dir(__builtins__)

Back 5

Outputs the list of all builtin functions.

Front 6

help(func)

Back 6

Shows the help file of the function 'func'.

Front 7

del gases[0]

Back 7

Delete the first element of the list gases.

Front 8

gases.append('Ne')

Back 8

The method append will append 'Ne' as the last element of the list gases.

Front 9

What are methods in Python?

Back 9

A method is a subroutine(or procedure) associated with a class.
file.method, a method is a function that 'belongs' to and operates on a specific chunk of data

Front 10

gases.count('He')

Back 10

Shows how many times the entry 'He' is on the list gases.

Front 11

gases.index('Ar')

Back 11

gives the index of the entry in the list gases.

Front 12

print(x)

Back 12

It will print the variable x and add one line.b

Front 13

What are the rules for legal names in Python?

Back 13

1. Names must start with a letter or _.
2. Names must contain only letters, digits, and _.

Front 14

What is the name convention in Python

Back 14

It is the pothole. My_Variable_long.

Front 15

What is the keyword to define a function in Python?

Back 15

It is 'def'. Example:
def my.function(x, y, z)
print(x, y, z)

Front 16

What is comment keyword?

Back 16

it is #

Front 17

What the keyword 'return' means?

Back 17

a keyword indicating the result of a function. Return statement is: return expression. Used in function definitions.

Front 18

What is a parameter?

Back 18

It is a variable that appears between the parentheses of a function definition. Parameters get their values to expressions in a function call.

Front 19

What is a string literal?

Back 19

It is a sequence of characters.

Front 20

How to import all the functions of a module in python 2.x ?

Back 20

from math import * # use * to import

Front 21

How to prefix the module being imported with a short name ?

Back 21

import matplotlib.pyplot as plt

Front 22

How to import the pi number?

Back 22

from math import pi

Front 23

How to generate n equally spaced coordinates from a start point to a stop ?

Back 23

linspace(start, stop, n) # from numpy import linspace

Front 24

How many elements is the output of: print(list[0:3])?

Back 24

The first three elements, but not the fourth(index 3), is not included.

Front 25

What the _ means when making operations ?

Back 25

it's a variable with the last value returned in the prompt

Front 26

What is the format of a dictionary in py ?

Back 26

var = { key1 : name1, key2 : name2}

Front 27

How assignments can be done on more than one variable "simultaneously" ?

Back 27

a, b = 3, 4 #on the same line.

Front 28

Which method remove white space in right end of a string ?

Back 28

name_of_var.rstrip()

Front 29

Which method remove white space in left end of a string ?

Back 29

name_of_var.lstrip()

Front 30

How to have basic functions for plotting, like

plt.plot(),plt,hist(),plt.show() and the like ?

Back 30

import matplotlib.pyplot as plt

Front 31

How to make a log scale to a graph ?

Back 31

plt.xscale('log')

Front 32

How to make a scatter plot ?

Back 32

plt.scatter(x,y)