Computer Languages and Representations

Question 1

What is a factor of the Software crisis and when did the Software crisis begin?

Answer 1

Began - 1960s

High cost of producing software - software costs have been rising as hardware costs have been falling

Question 2

How are Programs represented and Computation implemented in:

1. Functional Programming
2. Logic Programming
3. Finite State Machines

Answer 2

1. Programs are represented by expressions
   Computation is represented by reduction
2. Programs are represented by clauses
   Computation is represented by proof
3. Programs are represented by state machines
   Computation is represented by transitions

Question 3

What are the foundations in Functional and Logic programming?

Answer 3

Functional Programming - lambda calculus

Logic Programming - first-order logic

Question 4

Define a Function

Answer 4

A function transforms information recieved by inputs to information transmitted by output.

Question 5

What are arguments and results in functions?

Answer 5

Argument = Inputs
Results = Outputs

Question 6

What is a must for an equation to apply?

Answer 6

Argument must match the pattern for an equation

(Any argument matches a variable pattern)

Question 7

What is a Pattern?

Answer 7

A pattern may describe the structure of the argument and name its components

Question 8

What is a Guard?

Answer 8

A guard is a Boolean expression that must be true for the equation to apply.

(Guards often work with patterns)

Question 9

Define “otherwise”

Answer 9

A special final guard that is always true.

Question 10

How are functions used in programming?

Answer 10

The function f to an argument x is written as f x.

Question 11

What is a Type?

Answer 11

Set of values with the same usage and behaviour.

(All of the values in one of these sets are the same kind of thing such as an integer)

Question 12

What is a Type System?

Answer 12

The fundamental purpose of a type system is to prevent errors during the execution of the programs, by ensuring types match correctly.

Question 13

What is Type Checking?

Answer 13

Ensures types are used consistently, and that these errors are avoided.

Question 14

Define Static Type Checking

Answer 14

Happens before program execution

Question 15

Define Dynamic Type Checking

Answer 15

Happens during program execution

Question 16

What is a negative of Local Defintions?

Answer 16

Having all function at the top level of a script can lead to name space pollution - clashes caused by reuse of the same name.

Question 17

What is a Where Definition?

Answer 17

A where definition allows one to name a value, and to use it in an expression.

Question 18

What is a Let Definition?

Answer 18

A let definition allows one to name a value, and to use it in an expression.

Question 19

What are the steps for Polya’s heuristic strategies?

Answer 19

1. Understand the problem
2. Devise a plan
3. Carry out the plan
4. Look back and reflect

Question 20

Explain Understanding the problem in Polya’s heuristic strategies.

Answer 20

Involves careful study. May seem obvious, but failure to understand the problem often explains a failure to solve it.

Question 21

Explain Devising a plan in Polya’s heuristic strategies.

Answer 21

Involves identifying calclulations, computations or constructions that may be performed in order to obtain the solution

Question 22

What are 3 key questions when Devising a plan?

Answer 22

• Did you use all the data?
• Did you use the whole condition?
• Could you use a related problem, solved before?

Question 23

Explain Carrying out the plan in Polya’s heuristic strategies.

Answer 23

Involves performing the steps in sequence to give the solution.

Question 24

What are 2 key questions when Carrying out the plan?

Answer 24

• Can you see each step is correct?
• Can you prove each step is correct?

Question 25

Explain Reflecting in Polya’s heuristic strategies.

Answer 25

Taking time to consider what worked and what didn’t. The insights gained may make it easier to find solutions to future problems

Question 26

What are 3 key questions when Reflecting?

Answer 26

• Can you check the result?
• Can you check the argument?
• Can you use the result/method for some other problem?

Question 27

What is a design pattern?

Answer 27

It captures the idea of a good solution to a common design problem

They can make novices look like experts.

Question 28

What is the Generate-and-select design pattern?

Answer 28

Generator construct a large number of values that might be solutions to a problem.

Selector filters out those values that are solutions to the problem.

Question 29

What is the productivity paradox?

Answer 29

You can see computer age everywhere but in the productivity statistics

Question 30

What are the three explanations of the productivity paradox?

Answer 30

1. Uneven/concentrated gains
2. Implementation lags
3. Mismeasurement

Question 31

Explain Uneven/concentrated gains in relation to the productivity paradox.

Answer 31

The gains are in few productive firms and sectors with limited weight in the overall economy.

Question 32

Explain Implementation lags in relation to the productivity paradox.

Answer 32

It takes considerable time for a new technologies to achieve critical mass, or for necessary complementary ones to appear.

Question 33

Explain Mismeasurements in relation to the productivity paradox.

Answer 33

Adopting new technologies can lead workers to move on from more productive adopting sectors to less productive ones, and so to negligible aggregate productivity growth.

Question 34

How do Artificial Neural Networks (ANNs) work behind the scenes?

Answer 34

1. The core ANN is trained on text from the Internet to respond to a prompt with a list of most probable next words after the prompt
2. The core ANN is tweaked by scoring its responses to sample queries. A second NN is trained on these scores to predict the most likely one to be assigned to a prompt.
3. The second ANN is used in reinforcement learning to adjust the weights iin the core ANN so that its outputs are even most likely to satisfy humans
4. Sometimes, data from user responses to LLM responses is fed back to fine-tune for still better results

Question 35

What are the concerns when using the large language models?

Answer 35

1. Copyright
2. Education
3. Code quality
4. Code security
5. Not an expert

Question 36

What is the Copyright concern when using large language models?

Answer 36

Although the code produced is the melding of that from many sources, there may still be licensing problems

Question 37

What is the Education concern when using large language models?

Answer 37

Good solutions to many assignments can be completed directly, reducing their challenge and worth

Question 38

What is the Code quality concern when using large language models?

Answer 38

No guarantee of code quality when using a large language model, and a code review will need to be conducted before code is deployed.

Question 39

What is the Code security concern when using large language models?

Answer 39

No guarantee of code security when using a large language, and a security audit will need to be conducted before code is deployed