13: Data Types

Question 1

What are 5 kinds of data type?

Answer 1

String, character, float, boolean, integer

Question 2

What is meant by a primitive data type?

Answer 2

Any basic data type provided by a language as a fundamental building block

Question 3

What is an integer?

Answer 3

Any positive or negative whole number

Question 4

What is a real/float?

Answer 4

Any positive or negative real-world quantity that can be expressed as a number

Question 5

What is a string?

Answer 5

A collection of characters

Question 6

What is a boolean data type?

Answer 6

Used to represent one of two truth values associated with logic and Boolean algebra: True and False

Question 7

What is meant by casting?

Answer 7

Converting from one data type to another

Question 8

What are the highest and lowest numbers that can be represented using Sign and Magnitude?

Answer 8

127 and -127

Question 9

What are some rules to follow to represent a number in two’s complement?

Answer 9

• Write out positive version of the number
• Starting from the right-most digit (LSB) copy each of the digits exactly as they appear, up and including the first 1
• From that point on, swap the digits

Question 10

How do you do binary subtraction?

Answer 10

• Make the second number using two’s complement

- add

Question 11

What is the advantage of using floating point binary instead of normal binary?

Answer 11

gives greater flexibility as the range and precision of the numbers that can be stored in the same number of bits

Question 12

How does range relate to accuracy in floating point binary?

Answer 12

• the more bits assigned to the whole number part of the mantissa, the larger the number that can stored, but at the cost of accuracy of the fractional part

Question 13

What is the mantissa?

Answer 13

Number itself

Question 14

What is the exponent?

Answer 14

The position of the binary point in the number

Question 15

What do positive normalised numbers start with?

Answer 15

01

Question 16

What do negative normalised numbers start with?

Answer 16

10

Question 17

What steps would you take to convert 3.5 into a normalised floating point binary number?

Answer 17

• Write out 3.5 on a standard fixed-point number line
• Move the binary point so it moves between the 0 and the 1 (it is positive)
• As the binary point moved 2 to the left, the exponent must be -2