N5 SDD Revision

S4 SDD Revision

Software Design and Development

We need to be able to answer questions on each stage of the development process:

◦ Analysis – input, process and output
◦ Design – pseudocode algorithms, flowcharts and structure diagrams
◦ Implementation – all the code
◦ Testing – test data and types of error
◦ Evaluation – fitness for purpose, efficiency, robustness, readability

Multiple Choice

A program is to be created to allow users to calculate their BMI​

Body Mass Index (BMI) is a way to measure if your weight is in a healthy range for your height. BMI is calculated using the formula weight in kg divided by the square of your height in meters BMI = kg/m2

What would be the inputs for this program?​

• BMI

• BMI

  Height

  Weight

• Height

  Weight

Multiple Choice

A program is to be created to allow users to calculate their BMI​

Body Mass Index (BMI) is a way to measure if your weight is in a healthy range for your height. BMI is calculated using the formula weight in kg divided by the square of your height in meters BMI = kg/m2

What would be the output for this program?​

• BMI

• BMI

  Height

  Weight

• Height

  Weight

Multiple Choice

A program is to be created to allow users to calculate their BMI​

Body Mass Index (BMI) is a way to measure if your weight is in a healthy range for your height. BMI is calculated using the formula weight in kg divided by the square of your height in meters BMI = kg/m2

What would be the process for this program?​

• Multiply height and weight 

• Divide height by weight squared

• Divide weight by height squared

Open Ended

What type of design is shown?

Open Ended

What type of design is shown?

Open Ended

What type of design is shown?

Multiple Choice

Which would be an appropriate data type for forename?

• text

• integer

• string

• boolean

Multiple Choice

Which would be an appropriate data type for BMI?

• text

• integer

• string

• boolean

Multiple Choice

Which would be an appropriate data type for height?

• float

• character

• string

• boolean

Data Structures

We have 2 data structures

• Variable - stores one piece of data

• Array - stores a set number of data, always the same data type

Multiple Choice

The BMI program is extended to store a user's BMI once a month for a year. Which data structure should be used to store the 12 values?

• variable

• array

• loop

• algorithm

Multiple Choice

The BMI program is extended to store a user's BMI once a month for a year. Which declaration would create a data structure to hold these 12 values?

• BMI = (12)

• BMI = 0(12)

• BMI = (0*12)

• BMI =(0)*12

Multiple Choice

The BMI program is extended to store a user's BMI once a month for a year. Which declaration would create a data structure to hold these 12 values?

• Array of Intergers (12)

• Array of real (12)

Standard Algorithms

We have 3 standard algorithms

• Traversing a 1D Array

• Input Validation

• Running Total (within a loop)

Multiple Choice

Which algorithm is shown?

• Traversing a 1D Array

• Input Validation

• Running Total

Multiple Choice

Which algorithm is shown?

• Traversing a 1D Array

• Input Validation

• Running Total

Multiple Choice

Which algorithm is shown?

• Traversing a 1D Array

• Input Validation

• Running Total

Predefined Functions

These are prewritten snippets of code designed to perform a specific function. They save time as they are already written, do not need tested or coded and can be used over and over again.

We need to know:-

• Round - numerial function that will round to nearest whole number

• Random - numerical fnction that selects a number between two parameters

• Len - string function that counts the number of characters

Multiple Choice

Which predefined function is used in this program?

• Round

• Random

• Length

Multiple Choice

Which predefined function is used in this program?

• Round

• Random

• Length

Multiple Choice

Which predefined function is used in this program?

• Round

• Random

• Length

Multiple Choice

The averageBMI should be rounded to 2 decimal places. Which line of could would achieve this?

• averageBMI = round(averageBMI)

• averageBMI = round(averageBMI,0.00)

• averageBMI = round(averageBMI,2)

• averageBMI = round(averageBMI,2dp)

Testing

Once we have coded our programs we then need to test them.

We test for the following circumstances

• Normal

• Extreme

• Exceptional

Multiple Choice

In the adult BMI calculation program. Test data of 18 is entered for age.

What is that an example of?

• Normal

• Extreme

• Exceptional

Multiple Choice

In the BMI calculation program. Test data of 28 is entered for age.

What is that an example of?

• Normal

• Extreme

• Exceptional

Multiple Choice

In the BMI calculation program. Test data of "twenty four" is entered for age.

What is that an example of?

• Normal

• Extreme

• Exceptional

Error Types

Whilst testing we are also check ign for the following types of errors

• logic

• syntax

• execution (run time)

Multiple Choice

Which error has stopped this program from running?

If age <18

print("Invalid age!")

• logic

• syntax

• execution

Multiple Choice

The program runs and can return correct results but, when a user repeatedly enters 0 as their weight, the program crashes. Which type of error is this?

• logic

• syntax

• execution

Multiple Choice

The program runs and can return correct results but the expected values do not match the actual output.

Which kind of error is this?

• logic

• syntax

• execution

Program Evaluation

Our programs are evaluated against

• Fitness for purpose

• Efficiency

• Robustness

• Readability

Multiple Choice

Check that the code uses meaningful variable names, has internal commentary and leaves white space to separate parts of the code.

What is being evaluated here?

• Fitness for purpose

• Efficiency

• Robustness

• Readability

Multiple Choice

The program can accurately calculate, store and display a user's BMI.

• Fitness for purpose

• Efficiency

• Robustness

• Readability

Multiple Choice

The code uses arrays to store data and loops to carry out repeated sections of code.

• Fitness for purpose

• Efficiency

• Robustness

• Readability

Multiple Choice

If zero is entered for weight, the program will crash.​

• Fitness for purpose

• Efficiency

• Robustness

• Readability