Data representation

Question 1

what is a “set”

Answer 1

an disorganized collection of unique elements {finite or infinite}

Question 2

symbol for “Real Numbers”

Answer 2

R

Question 3

symbol for “Irrational numbers”

Answer 3

R-Q

Question 4

symbol for “Rational numbers”

Answer 4

Q

Question 5

symbol for “Integers”

Answer 5

Z

Question 6

symbol for “Natural numbers”

Answer 6

N

Question 7

what are “Ordinal numbers” and what do they describe

Answer 7

Natural numbers that describe the position of values in a set

Question 8

what is “Enumeration”

Answer 8

letters being used in a set of ordinal numbers

Question 9

what is a use of “natural numbers”

Answer 9

counting

Question 10

what is a use of “ordinal numbers”

Answer 10

ordering

Question 11

which includes all numbers

Answer 11

Real

Question 12

which includes numbers that cant be expressed as a fraction

Answer 12

Irrational

Question 13

which numbers include fractions (and integers)

Answer 13

Rational

Question 14

“Integers” include natural numbers but the opposite isn’t true why

Answer 14

Natural numbers don’t include negatives, as they are an infinite set above zero

Question 15

Nyquist’s theorem

Answer 15

sample rate must be at least double the highest frequency

Question 16

What are 4 methods of error checking?

Answer 16

parity bits, majority voting, checksum and check digit (which is just data validation)

Question 17

routers role in sending messages from private devices across a network

Answer 17

Routers do network address translation to switch the private IP with their own public IP

Question 18

Fixed point (don’t recall just read)

Answer 18

assume unsigned

0.343752=0.688
0.6882=1…ans
0.ans2=0…ans
0.ans2=1…ans
1111.0101

Question 19

Floating point

Answer 19

assume 2s compliment(signed)

Question 20

effect of the exponent when positive and negative (floating point)

Answer 20

Like standard form but base 10 is replaced by base 2

Mantissa: is binary number (fixed point)
Exponent: multiplication value

Question 21

normalisation

Answer 21

“memory efficiency”
positive begins 0.1 instead of 000.01
negative begins 1.0 instead of 111.01

Question 22

Kilo vs Kibi

Answer 22

10 to 3 vs 2 to 10

Question 23

What is Meta Data

Answer 23

Data About Data (i.e location) that increases file size

Question 24

Effect of allocating more bits to the Mantissa

Answer 24

Greater precision of the number

Question 25

Effect of allocating more bits to the Exponent

Answer 25

Greater range of numbers can be represented

Question 26

Benefits vs Negatives of a Bitmap Image

Answer 26

++
1. each pixel can be manipulated
(greater detail)
2. fixed file size
–
1. loses quality when enlarged
2.Meta data stored on each pixel means file size can get very large

Question 27

Vector Images Benefits

Answer 27

1. Can be scaled without losing quality
2. each object can be manipulated (instead of individual pixels)
   3.Objects can be stacked (useful for map imaging)
3. Less storage space for simple shapes

Question 28

Vector Images Negatives

Answer 28

1. difficult to make complex/detailed shapes from instructions
2. can take more storage when representing images with high color depth

Question 29

Analogue to digital converter (ADC)

Answer 29

1. Audio recorded and converted into current
2. Sampled at regular Intervals for amplitude
3. values are quantized into discrete values
4. represented by binary values

Question 30

Midi Sound

Answer 30

electronic instruments connected to computer give stored event messages to device on what audio to play

Question 31

Midi Sound Benefits vs Negatives

Answer 31

++
1. Smaller size // no BG noise
2. easier to manipulate
–
1. Less realistic
2. Cannot Mimic Human vocals