Core Elements of Programs

Question 1

What are the types of programming language?

Answer 1

Compiled (High level language)
Instructions are converted to low level ahead of time

Interpreted (Low level language)
Instructions are processed on the fly at the basic level of the computer

Interpreted (High Level language)
Instructions are processed on the fly at a high level which enables more abstract computation

Question 2

What is a program?

Answer 2

A program/script is a sequence of definitions and commands. It manipulates data objects.
Definitions are evaluated.
Commands are are executed by the shell.

Question 3

What is a shell?

Answer 3

Provides access to operating system services.

Question 4

What is a command?

Answer 4

A command/statement instructs the interpreter to do something.

Question 5

What are the types of data objects?

Answer 5

Scalar: int (5, 47)
float (4.7, 3.14)
bool (True, False)
NoneType

Non-scalar:

Question 6

What is an expression?

Answer 6

Composed of operators and data objects.

Question 7

What arithmetic operators are used on ints and floats?

Answer 7

i+j -  Sum
i-j  -  Difference
i*j  -  Multiplication
i/j - Division
i//j  -  Division (int)
i%j -  Remainder
i**j -  Power

Question 8

What comparison operators are used on ints and floats?

Answer 8

i>j - Greater than
i>=j - Greater than or equal to
i

Question 9

What logic operators are used on bools?

Answer 9

a and b - True if both are True
a or b - True if either are True
not a - True if a is False, False if a is True

Question 10

What are type conversions?

Answer 10

float(3) = 3.0
int(3.4) = 3

Question 11

How do you bind values to variables and names?

Answer 11

=

Question 12

What is operator overloading?

Answer 12

Using the same operator to achieve different things based on the type of object.

Depending on the type of the object, number or string the operator will decide what the right operation is to do.

Question 13

What is string indexing vs slicing?

Answer 13

Indexing selects an individual letter from a string of characters

Slicing selects a portion of a string

Question 14

How do you index an individual character from a string?

Answer 14

‘abc’[2]&raquo_space;> ‘c’

Question 15

How do you slice a set of characters from a string?

Answer 15

‘Python’[1:5]&raquo_space;> ‘ytho’

‘Python’[0:0:2]&raquo_space;> ‘Pto’

Question 16

How do you denote a comment in a script?

Answer 16

#

Question 17

How do you prompt for user input?

Answer 17

name = raw_input(‘Enter your name:’)

Question 18

What are the syntax for nested conditionals?

Answer 18

if - checks a specific value
elif - checks a specific value if not already found
else - default if no criteria are met

Question 19

How do you get the remainder from numbers?

Answer 19

%

Question 20

How do you print a calculation externally without the value being used for computation?

Answer 20

print(

i.e: print(5+3)

Question 21

What are the arguments for string slicing?

Answer 21

‘string’[start:stop:step]

Question 22

When changing the value of an object that is bound to a value what is important to consider?

Answer 22

Changing that value will not effect any other objects that previously used the object

Question 23

When using strings why use “ or ‘?

Answer 23

“is used if the string contain’s an apostrophe”

Question 24

What is the syntax for a while loop?

Answer 24

while

Question 25

What does a += b stand for?

Answer 25

a = a + b

Question 26

What does a -= b stand for?

Answer 26

a = a - b

Question 27

What does a*= b stand for?

Answer 27

a = a * b

Question 28

What does a /= b stand for?

Answer 28

a = a / b

Question 29

What is the equivalent to a = a + b?

Answer 29

a += b

Question 30

What is the equivalent to a = a - b?

Answer 30

a -= b

Question 31

What is the equivalent to a = a * b?

Answer 31

a *= b

Question 32

What is the equivalent to a = a / b?

Answer 32

a /= b

Question 33

What is the syntax to stop a loop executing?

Answer 33

break

Question 34

When putting a conditional piece of syntax what do you need to remember?

Answer 34

Close it with a :
if ans = 0:
while ans <= 5:

Question 35

How do you find the absolute value of a number?

Answer 35

abs(

Question 36

How do you get a sequence of integers

Answer 36

range(n) = [0, 1, 2, 3, ..., n-1]
range(m,n) = [m, m+1, ..., n-1]

Question 37

What is the while loop?

Answer 37

Repeats a statement while a given condition is true
Unbounded number of iterations

while x < 5:

Question 38

What is the for loop?

Answer 38

Repeats a statement a given number of times

for i in range(4):
for i in s: #Reference string directly

Question 39

What are the arguments for range?

Answer 39

range(start,stop,step)

Question 40

What are the ways of concatenating strings?

Answer 40

print("I am", x, "years old")
#Used to concatonate int variables directly
print("I am " + str(x) + " years old
#Can only concatenate string type variables

Question 41

What is an immutable object?

Answer 41

Its value cannot change
s[0] = “b” #Error because strings are immutable
s = “b” + s[1:] #Must rebind s

Question 42

How do you assign expressions(code) to conditionals?

Answer 42

Indentation

Question 43

When using input, what type variable is stored?

Answer 43

String

Question 44

What parameters constitute an object?

Answer 44

Identity
Type
Value

Question 45

What is lexicographic order?

Answer 45

Alphabetic order, is inherently known in python for strings