D278 EXAMINATION QUESTIONS AND ANSWERS
What is an editor? - A program that allows you to write code
What is a compiler? - A program that produces other programs. The compiler does all the
work at once and then runs the new program. We're translating the code we wrote to computer
code all at once. This is often when we produce an .exe (executable) file.
What is an interpreter? - A program that runs code one line at a time. Instead of
converting all of the code at once it runs each line as it's needed. It interprets that specific line
from your code to computer code.
What is an operator and what does it do? - An operator takes two operands (values) and
does something with them. It is an object capable of manipulating a value. If it is a comparison
or logical operator it would compare to see if they are similar or dissimilar. If it is a
mathematical operator it would perform mathematical calculations.
What is an expression? - something that has a value.
What is the difference in a terminal and non-terminal expression? - A terminal is a final
value, while a non-terminal can be reduced further.
What is proper Python grammar for making an expression? - Expression → Expression
Operator Expression
The Expression non-terminal that appears on the left side can be replaced by an Expression,
followed by an Operator, followed by another Expression. For example, 1 + 1 is an Expression
Operator Expression.
What is a variable? - a name that refers to a value
What are the three main types of data covered? How do you declare each one? - string is
a sequence of characters surrounded by quotes, either single or double
example: myVar = "string data"
Integer is a number - example: myVar = 33
Boolean is a true or false value - example: myVar = True
What is grammar used for in programming? - In a programming language like Python, the
code must match the language grammar exactly. When programming language grammar is not
, followed the interpreter will return a Syntax Error message. This means that the structure of the
code is inconsistent with the rules of the programming language.
How do you change the value of a variable with Python? - Using the = character to assign
a new value
x=6
x=9
print x # would print out 9
How to do you join multiple variables together with string data in Python? What is this called? -
Using the + sign to concatenate the values
What does it mean to index a string? How do you do that with Python code? - This is
what we call selecting a sub-sequence of a string. You do this in Python by specifying the
character you want to access by its index position. Index position begins at 0. For example, this
code would print out the letter J:
name = 'John'
print name[0]
What does it mean to slice a string? How do you do that with Python code? - Slicing is
simply obtaining a subset of data from a string. You may have also heard this called string
extraction. You do this in Python by specifying the index position where you want to begin and
where you want to end. Everything from the starting point up until the end point will be
extracted. For example, this code would print out "Jo":
name = 'John'
print name[0:2]
+- concatenate or add
=- assignment
*- multiply
-- subtract
/- divide
%- Modulos, does division and returns the remainder
What is an editor? - A program that allows you to write code
What is a compiler? - A program that produces other programs. The compiler does all the
work at once and then runs the new program. We're translating the code we wrote to computer
code all at once. This is often when we produce an .exe (executable) file.
What is an interpreter? - A program that runs code one line at a time. Instead of
converting all of the code at once it runs each line as it's needed. It interprets that specific line
from your code to computer code.
What is an operator and what does it do? - An operator takes two operands (values) and
does something with them. It is an object capable of manipulating a value. If it is a comparison
or logical operator it would compare to see if they are similar or dissimilar. If it is a
mathematical operator it would perform mathematical calculations.
What is an expression? - something that has a value.
What is the difference in a terminal and non-terminal expression? - A terminal is a final
value, while a non-terminal can be reduced further.
What is proper Python grammar for making an expression? - Expression → Expression
Operator Expression
The Expression non-terminal that appears on the left side can be replaced by an Expression,
followed by an Operator, followed by another Expression. For example, 1 + 1 is an Expression
Operator Expression.
What is a variable? - a name that refers to a value
What are the three main types of data covered? How do you declare each one? - string is
a sequence of characters surrounded by quotes, either single or double
example: myVar = "string data"
Integer is a number - example: myVar = 33
Boolean is a true or false value - example: myVar = True
What is grammar used for in programming? - In a programming language like Python, the
code must match the language grammar exactly. When programming language grammar is not
, followed the interpreter will return a Syntax Error message. This means that the structure of the
code is inconsistent with the rules of the programming language.
How do you change the value of a variable with Python? - Using the = character to assign
a new value
x=6
x=9
print x # would print out 9
How to do you join multiple variables together with string data in Python? What is this called? -
Using the + sign to concatenate the values
What does it mean to index a string? How do you do that with Python code? - This is
what we call selecting a sub-sequence of a string. You do this in Python by specifying the
character you want to access by its index position. Index position begins at 0. For example, this
code would print out the letter J:
name = 'John'
print name[0]
What does it mean to slice a string? How do you do that with Python code? - Slicing is
simply obtaining a subset of data from a string. You may have also heard this called string
extraction. You do this in Python by specifying the index position where you want to begin and
where you want to end. Everything from the starting point up until the end point will be
extracted. For example, this code would print out "Jo":
name = 'John'
print name[0:2]
+- concatenate or add
=- assignment
*- multiply
-- subtract
/- divide
%- Modulos, does division and returns the remainder
