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Video Title: Function Oriented Design
Description: Function Oriented Design
Watch more Videos at https://www.tutorialspoint.com/videotutorials/index.htm
Lecture By: Mr. Arnab Chakraborty, Tutorials Point India Private Limited
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In this session, let us discuss function
oriented design.

What is a function oriented design?

And what are its different features?

So, a function oriented
design, the system comprises

of many smaller subsystems
and also known as functions.

These functions are capable of performing
significant task in the system.

The system is considered as top view of
all these functions.

So, whenever we are having some dedicated
task, we can write a separate function for

it, so that the function execution will
accomplish the task execution.

So, whenever we are considering functional
design, then you can consider that system

is consisting of multiple different
co-operating functions, and each other

function might be executing a specific
dedicated task.

Function oriented design inherits some
properties of structure design,

where divide and conquer methodology is
used.

So, divide and conquer
methodology means, we we

shall divide our whole
problem into sub problems.

And for each and every sub problem,
depending upon the dedicated task,

we will be writing our respective function
for that.

And that is the main key theme in our
function oriented design.

This function design mechanism divides the
whole system into smaller functions,

which provides means of
abstraction by concealing

the information and their
respective operations.

So, from the top view, we can get the
different functions, but how these

functions are having their respective
information residing in that and what is

their respective operations and respective
codes are written.

So, it is this functions are concealing
them.

So, these function modules can share
information Function among themselves by

means of information passing and using
information available globally.

So, whenever one function will interact
with another function, then the function

which will be calling the other one may
pass some parameters, may pass some

information, so that the information can
be accessed from the other functions body.

And functions can do the communication
through some global data set.

Another characteristics of function is
that when, a program calls a function the

function changes the state of the program.

So, whenever a function will be called the
function may change the state of the

program which sometimes is not acceptable
by, the other modules.

So, function-oriented design works,
well where the system state does not It

does not matter and program as functions
work on input rather than on a state.

So, this particular functional design is
applicable in those applications where

state of the system will be ignored and
only passing parameters, passing

information between two cooperating
functions they can communicate each other.

So, design process, the
whole system is seen as how the

data flows in the system by
means of data flow diagram.

So, in a separate video we have discussed
what is this DFD and what are the

different levels of DFD.

So, actually in case of DFD, we are trying
to put one diagram, we are want to draw

one diagram which will
depict that how the data will

be flowing from one
subsystem to another subsystem.

DFD depicts how function change data and
step of the enter system.

The enter system is logically broken down
into smaller units known as a function on

the basis of their operations in the
system.

Each and every function must be dedicated
to a certain operation or task completion.

Each function is then described at large.

Then each and every function will be
described at large.

So, now after getting this respective task
which is going to get accomplished by the

respective function, we can define this
function into more details.

So, this is known as function-oriented
design.

So, we have discussed into more details
about this respective design technique.

Thanks for watching this video.