Introduction to Flow Chart
• It is pictorial representation of process
of a system or processes.
• Types of Flow charts
– Program Flow Chart
– System Flow chart
– Data Flow Diagram
1.Program Flow Chart
It is graphical description of sequence of logical operations
performed by the computer in a computer program. PFC are
drawn by use of specific symbols.
2.System Flow Chart
It is graphical description of relationships among the inputs,
outputs and processes in an IS (modeling systems in physical
terms). SFC are drawn by use of specific symbols.
3.DFD (Data Flow Diagrams)
It shows how the data moves within a system. DFD
are also drawn by some specific symbols
Purpose of Program Flow chart:
• Clarification of logic of a problem
• Effective Analysis of actions resulting from a
set of conditions
• Sorting out steps in a program
• Helping programmers for coding
• Efficient coding
• Easy debugging
• Documentation for program logic
• Used for Information System Audit
Flow charting Disadvantages
• Difficult to draw for complex problems
• If modification required then completely redrawn
• When the programmer has changed the
program as per requirement then programmer
has to redraw its flow chart
• Tasks start & finish dates , durations and
resources are not known
• Physical resource location is not known
• Difficult to distinguish important tasks
Program Flow Chart Symbols
DFD Symbols
Processing Operation
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Arithmetical Calculation
Reading Input
Producing Out put
Comparison
Moving data
Initializing value
Branching
Branching
• The computer executes the program
instruction in sequence. If computer has to
broken the sequence then a branch
instruction is required.
• Types of Branch Instruction
– Conditional Branching( When Branching is
depend
– Unconditional Branching( When branching is
independent of any comparison instruction
• Control Instruction:
It includes the following instructions
- start/stop
- Instructions for allocation of storage
- Checks for hardware errors
Loop:
A sequence of instructions that are executed
repeatedly until a specified condition is
satisfied.
Types of FC w.r.t Level of
Details
• Macro Level
– It contains the a big picture or macro level
view of a process.
• Mini Level
– It contains details between the a big
picture and fine details of a process.
• Micro Level
– It Contains detailed description of process
steps.
• Linear FC:
– It displays the sequence of work steps in the
process.
– Advantages:
• Can identify rework
• Can identify redundant
• Can identify unnecessary steps in the process
• Deployment FC:
– It shows the actual process flow and identifies
peoples or groups involved at each step.
– Advantages
• It shows where people or group fit into the process
• It also show how they relate to one another throughout
the process
• Opportunity FC:
– It differentiates those process activities that add
value from those that add only cost
• Value Add Activities:
– These activities are essential for producing
product and service.
• Cost added only activities
– These activities are not essential for
producing the required products and services,
they may be added as future preventive
measures.