IPO charts

A problem can be broken down into 4 components:

1. Input – any data that is needed to solve the problem

2. Processing – the task that will be carried out to solve the problem

3. Output – the end result of the problem

4. Storage – variable are used to store data/values to perform calculation

The IPO (Input, Processing & Output) chart can be used to analyse a problem. This is a table with three columns, which represent three components: input, output and processing. Storage component is not shown.

Follow these 5 steps to complete an IPO Chart:

1. Write the input (what is needed from the person using the algorithm).
2. Write the output (the end result that is stated in the problem).
3. In the processing column write “get” and anything that is under the input column. If nothing is under the input column, leave out this step.
4. Ask yourself the following question. “What do I have to do with the inputs in order to produce the desired output?” Then write down what should be done.
5. Write “display” and anything under the Output column.

E.g. A program is required to read three numbers, calculate and print their total.

Three numbers are needed so write “3 numbers” under INPUT

The question asks for the total to be printed so Sum or Total can be used.

• Write down the word that is followed by 3 numbers.
• Write what should be done to produce the total which is “Calculate the total”
• Write down the word display followed by total.

A problem can be broken down into 4 components:

1. Input – any data that is needed to solve the problem

2. Processing – the task that will be carried out to solve the problem

3. Output – the end result of the problem

4. Storage – variable are used to store data/values to perform calculation

The IPO (Input, Processing & Output) chart can be used to analyse a problem. This is a table with three columns, which represent three components: input, output and processing. Storage component is not shown.

Follow these 5 steps to complete an IPO Chart:

6. Write the input (what is needed from the person using the algorithm).
7. Write the output (the end result that is stated in the problem).
8. In the processing column write “get” and anything that is under the input column. If nothing is under the input column, leave out this step.
9. Ask yourself the following question. “What do I have to do with the inputs in order to produce the desired output?” Then write down what should be done.
10. Write “display” and anything under the Output column.

E.g. A program is required to read three numbers, calculate and print their total.

Three numbers are needed so write “3 numbers” under INPUT

The question asks for the total to be printed so Sum or Total can be used.

• Write down the word that is followed by 3 numbers.
• Write what should be done to produce the total which is “Calculate the total”
• Write down the word display followed by total.

HIPO stands for Hierarchical Input Process Output. HIPO diagram assesses the system and facilitates documentation. It organises the software system’s modules into a hierarchy. HIPO diagrams can be used to get a high-level picture of the system’s functions. 

The functions are further divided into sub-functions, using HIPO diagrams demonstrating the system functions.

HIPO diagrams are excellent for documentation. By presenting the system’s structure in a graphical format, designers and managers may quickly comprehend it.

Advantages of HIPO

1. Offer more detail than other types of documentation.
2. Each module’s input and output are properly labelled.
3. Can be used to quickly determine what modules call the module under investigation.

Disadvantages of HIPO

1. The biggest downside of HIPO is that the documentation for a programme can become quite large: each module has its page, regardless of its actual size.
2. Structure charts and pseudocode are more extensively utilised than HIPO charts.
3. HIPO does not provide any data flow or control flow information.

Example of HIPO Diagram