Flowchart Symbols & examples

 

§  The pictorial representation of an algorithm with specific symbols for instructions & arrows showing the sequence of operations is known as “FLOWCART”.

§  The basic geometric shapes to denote different types of instructions. And these boxes are connected by solid lines with arrow mark to indicate the flow of operations.

§  An algorithm is converted into a flowchart  & then instructions are expressed in some programming language.

§  The main advantage of this two-step approach . That is ,while drawing a flowchart one is not concerned with the details of the elements of programming language.

§  Since a flowchart show of operations in pictorial form, any error in the logic of the procedure can be detected more easily than in a program.

 

FLOWCHART SYMBOLS

1. Terminal

§  It is used to indicate the beginning (START) & ending (STOP) in the program logic flow.

§  It has the shape of an ellipse

2. Input/Output

§  The parallelogram is used as the input/output symbol.

§  It will be attached with one entry flow & one exit flow.

3. Process

§  A rectangle is used to represent the processing step.

§  Arithmetic operations such as addition, subtraction, multiplication, division

 4. Decision

§  The Rombus is used as decision symbol

§  To indicate a point at which a decision has to be made.

5. Flow lines

§  Flow lines with arrow heads are used to indicate the flow of operations.

6. Connector

 When flowchart becomes too long to fit /connect with this symbol.

Manual Input flowchart shapes show process steps where the operator/ user is prompted for information that must be manually input into a system.

a. ON-PAGE Connector  

Flowchart sections can be connected with two different symbols. The circle connects sections on the same page, and the home base plate connects flowcharts from page to page. Inside these two symbols, the programmer writes letters or numbers. The on-page connector uses letters inside the circle to indicate where the adjoining connector is located. A "1" connects to a "1", a "2" to a "2", etc.

 b. OFF-PAGE Connector

 The off-page connectors use the page number where the next part or the previous part of the flowchart is located. On- and off-page connectors have either an entrance or an exit.

Other Symbols used

1. Predefined process

A Predefined Process symbol is a marker for another process step or series of process flow steps that are formally defined elsewhere. This shape commonly depicts sub-processes (or subroutines in programming flowcharts).

2. Manual Operations 

Manual Operations flowchart shapes show which process steps are not automated. In data processing flowcharts, this data flow shape indicates a looping operation along with a loop limit symbol (which is not supported by Microsoft Office, but a Manual Operation symbol rotated 180° will do the trick.)

3.Database

Also referred to as the “Data Symbol,” this shape represents data that is available for input or output as well as representing resources used or generated.

4.Document symbol 

Represents the input or output of a document, specifically. Examples of and input are receiving a report, email, or order. Examples of an output using a document symbol include generating a presentation, memo, or letter.

 

5. Delay

The Delay flowchart symbol depicts any waiting period that is part of a process. Delay shapes are common in process mapping.

 

6.  Preparation

As the names states, any process step that is a Preparation process flow step, such as a set-up operation.

7. Merge

Shows the merging of multiple processes or information into one.

 





 



Advantages of Flowchart

 Better communication

 Effective analysis

 Effective synthesis

 Efficient coding

 

Dis advantages of Flowchart

 Very time consuming for large complex program

 If any change /modify in the logic of the algorithm, usually requires a completely new flowchart

 There are no std determining the amount of details.

 

Ex:
















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