Program Development Life Cycle

The development of a program in any programming language takes a series of steps. The Program Development Life Cycle (PDLC) is a step-by-step approach to the development of a computer program in any programming language. The PDLC is composed of six steps:

a) Problem Definition: This phase of the PDLC includes an explanation of what needs to be developed. The main task at this stage is to define the problem in way that leads to a clear understanding of what the entire process is about.

b) Problem Analysis: The analysis phase requires specification of variables, functions and other parameters that will be useful in the program development process.

c) Algorithm Design: Algorithm design involves writing down sets of procedures that will be used to solve particular problems.

d) Coding and Documentation: The fourth phase involves writing down codes based on the previously designed algorithms. The codes can be written in different programming languages, based on user and developer’s preferences.

e) Testing and Debugging: The code is executed to identify any errors in the procedural flow of instructions. The program developer improves the program based on the identified bugs.

f) Implementation and Maintenance: The final phase involves adoption of the developed program. Here, the users navigate the system and in case of any flaws, the program developer adjusts the program based on the feedback. The maintenance phase also involves addition of parameters and functions based on the changes identified by the users.

Program Design Tools

Program development tools are material or objects that support the development of a program. There are five main program development tools in use nearly in all program design approaches. They include decision tables, decision trees, pseudocode (structured language), algorithms and flow charts. The table below provides a detailed explanation of each of the tools.

Tool

Description

Advantages and Disadvantages

Flow Charts

A flowchart is a graphical illustration of an algorithm. Flowcharts use symbols and shapes to signify different tasks. The symbols are linked using flowlines that also indicate the sequence of execution of the operations.

An advantage of using flowcharts is that the language can be used in any programming language. The chart also provides a comprehensible documentation for the user because it is easy to understand. The fact that there is a single flow of operations eliminates ambiguity. A limitation of the use of flow-charts is that its preparation is time-consuming.

Algorithms

An algorithm is a series of steps used to solve a problem. It should be simple and easy to understand. It should also have a finite number of steps.

An advantage of using algorithms is that they provide a finite number of steps towards problem-solving. Also, algorithms explain to the user how the program works. A disadvantage is that an error in algorithm design alters the whole program.

Decision Table

Made up of two sections (conditions and actions), a decision table leads the program developer to an unambiguous solution to a problem. It is used to define a course of action towards problem-solving.

Decision trees have the benefit of eliminating ambiguity. However, their preparation and application can be tedious and time-consuming

Decision Tree

Decision trees are quite similar to decision tables, except for the structure. The decision trees provide a pictorial hierarchical approach to finding the most appropriate solution.

Decision trees are easier to design and follow. They also provide a clearer decision on the most applicable solution.

Pseudocode

A pseudocode is a preliminary code that is developed before writing down the actual executable code. They are mostly written in understandable English language.

Pseudocodes guide the program developer towards developing the actual code. They also help in determining the most appropriate algorithmic flow of operations. Pseudocodes, if improperly arranged, can be misleading to the program developer.