Difference between Top down and bottom up approaches for a
given project ?




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Difference between Top down and bottom up approaches for a given project ?..

Answer / reejusri

These are two design approaches, which can be explained as:
You can imagine a tree like structure , in which when you
are following top-down appoarch you move from root node to
leaf node and when you follow bottom-up apprach you follow
leaf node to root node.

Top-down approach:
In this an overview of the system is first formulated,
specifying but not detailing any first-level subsystems.
Each subsystem is then refined in yet greater detail,
sometimes in many additional subsystem levels, until the
entire specification is reduced to base elements.

Bottom-up approach:
In this approach the individual base elements of the system
are first specified in great detail. These elements are
then linked together to form larger subsystems, which then
in turn are linked, sometimes in many levels, until a
complete top-level system is formed.

Is This Answer Correct ?    248 Yes 62 No

Difference between Top down and bottom up approaches for a given project ?..

Answer / shahidnx

First thing Top down and bottom up are designing approaches.
As simple, in top down approach,first we are designing the
main module(i.e main function) and in that we will decide
what all other modules to be include then we will design all
other sub modules..this approach is used C prog language.

In bottom up approach, just contrast to top down,first we
design all the sub modules related to application then we
design main module and in that we will decide what are the
modules to be include.. for ex: we can design any no of
classes and in main only required classes and their
functions can be used ...this approach is used in c++ ......

Is This Answer Correct ?    108 Yes 12 No

Difference between Top down and bottom up approaches for a given project ?..

Answer / koteraj

Top down design proceeds from the abstract entity to get to
the concrete design. Bottom up design proceeds from the
concrete design to get to the abstract entity.

Top down design is most often used in designing brand new
systems, while bottom up design is sometimes used when one
is reverse engineering a design; i.e. when one is trying to
figure out what somebody else designed in an existing system.

Bottom up design begins the design with the lowest level
modules or subsystems, and progresses upward to the main
program, module, or subsystem. With bottom up design, a
structure chart is necessary to determine the order of
execution, and the development of drivers is necessary to
complete the bottom up approach.

Top down design, on the other hand, begins the design with
the main or top-level module, and progresses downward to the
lowest level modules or subsystems.

Real life sometimes is a combination of top down design and
bottom up design. For instance, data modeling sessions tend
to be iterative, bouncing back and forth between top down
and bottom up modes, as the need arises.

Is This Answer Correct ?    105 Yes 35 No




Difference between Top down and bottom up approaches for a given project ?..

Answer / manish

top to down approach :-c
button to up approach :-c++
Top down design, on the other hand, begins the design with
the main or top-level module, and progresses downward to the
lowest level modules or subsystems.

Real life sometimes is a combination of top down design and
bottom up design. For instance, data modeling sessions tend
to be iterative, bouncing back and forth between top down
and bottom up modes, as the need arises.

Is This Answer Correct ?    45 Yes 29 No

Difference between Top down and bottom up approaches for a given project ?..

Answer / bintu

Top-down approach:-
In an over view of system is formulated specifying but not
detailing subsystems.Each subsystem is then refined in yet
greater detail,untill the entire specification is reduced to
base elements.
Bottom-up approach:-
The individual base elements of system are specifies in
great details.These elements are linked together to form
larger subsystems;untill a complete top-level system is formed.

Is This Answer Correct ?    17 Yes 7 No

Difference between Top down and bottom up approaches for a given project ?..

Answer / digvijay singh yadav

in top down approach every module don't have enough information regarding their task due to further explain at initial state so it require to be complete in next step.
while on the other hand in bottom up approach all module mostly have enough information and this module go to get abstraction

Is This Answer Correct ?    8 Yes 1 No

Difference between Top down and bottom up approaches for a given project ?..

Answer / rahul agrawal

Simplest and main difference is...this two are process of solving program........
So in top down it breaks the main program in sub programs then all the sub programs are being solved then after solving it merge them all in one function to provide exact output.....so 1st we have top as a main function ok...then we break it into sub function can be taken as down...so it approach as top to down...

In the same way in c++....program is already in sub functions....it directly solve this problems and merge them together for exact output....so what is happening here that Bottom as a sub function and Up as a merge function..so it approach as bottom to up.....
....Thanks 4 reading

Is This Answer Correct ?    8 Yes 2 No

Difference between Top down and bottom up approaches for a given project ?..

Answer / pankaj

top-down approach is time consuming  type of approach
and bottom-up approach is less time consuming type of approach

Is This Answer Correct ?    8 Yes 4 No

Difference between Top down and bottom up approaches for a given project ?..

Answer / prakash kumar mishra

Pops are considered as a top down approach because first of
all we think about what are functions required. Example of
planning. And then implementation part is done. Where as in
oops first we make small module and latter we link each
other. Example for making a building we make all the
required instrument or relevant module like piller,rod then
the work is being done.

Is This Answer Correct ?    5 Yes 2 No

Difference between Top down and bottom up approaches for a given project ?..

Answer / arjun rajput

the basic difference is that generally Top down approach is occered in C and not in c++

Is This Answer Correct ?    6 Yes 5 No

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