User Account

All Pages

What is Polyphase Sort, Data Structure & Algorithms

Assignment Help:
One of the best known methods for external sorting on tapes is the polyphase sort.

Principle: The basic strategy of this sort is to distribute ordered initial runs of predetermined size on the available tapes and then to repeatedly merge these runs in multiple phases in which each phase has a predetermined number of merges before a new target tape is selected.

To distribute the initial runs a Fibonacci distribution is adopted. After the distribution of the runs according to Fibonacci distribution, the merging procedure is continued until the tape with the least number of run lists is empty. When this occurs the remaining working tapes are logically rotated such that the newly emptied tape becomes the new target tape and the old target tape then becomes one of the working tapes to be merged. The sort ends when all runs are merged into one.

Let the number of tapes be T and p = T - 1. The Fibonacci distribution for p = 3 is given.

Level

s
Tape
Total number of runs
1
2
3
1
0
0
1
1
2
1
1
1
3
3
1
2
2
5
4
2
3
4
9
5
4
6
7
17
6
7
11
13
31
7
13
20
24
57
8
24
37
44
105
9
44
68
81
193
Algorithm:

1. Let A be the list of N unsorted elements and R be the number of runs.

2. Let T1, T2, T3 and T4 be the tapes on which sorting is done.

3. Split the list A into R=N runs so that each run has only one element.

4. If R is not equal to perfect Fibonacci distribution then add dummy records to bring up perfect Fibonacci distribution.

5. Distribute the records in the remaining tapes according to the Fibonacci distribution.

6. Merge 3 runs, one from each tape and put into next empty tape.

7. Repeat step 6 till a single run is generated.

Related Discussions:- What is Polyphase Sort

What is binary space partition, Binary Space Partition A binary space-p...

Binary Space Partition A binary space-partitioning (BSP) tree is an efficient method for determining object visibility by painting surfaces onto the screen from back to front,

Multiplication, Implement multiple stacks in a single dimensional array. Wr...

Implement multiple stacks in a single dimensional array. Write algorithms for various stack operations for them.

BINARY SEARCH, GIVE TRACE OF BINARY SEARCH ALGORITHM BY USING A SUITABLE EX...

GIVE TRACE OF BINARY SEARCH ALGORITHM BY USING A SUITABLE EXAMPLE.

In order post order, illlustraate the construction of tree of a binary tree...

illlustraate the construction of tree of a binary tree given its in order and post order transversal

Logic circuits, the voltage wave forms are applied at the inputs of an EX-O...

the voltage wave forms are applied at the inputs of an EX-OR gate. determine the output wave form

Just a quick couple questions, I was wanting to know where this web site wa...

I was wanting to know where this web site was created. My second question is,,, are the online tuters accredited teachers? If they are, are they only working for the website or ma

A binary tree of depth "d" is an almost complete binary tree, A binary tree...

A binary tree of depth "d" is an almost complete binary tree if  A) Every leaf in the tree is either at level "d" or at level "d-1"  B)  For any node "n" in the tree with a

Linked lists, algorithms

algorithms

Boar corloring, Board coloring , C/C++ Programming

Board coloring , C/C++ Programming

Define big oh notation, Big oh notation (O) : The upper bound for the funct...

Big oh notation (O) : The upper bound for the function 'f' is given by the big oh notation (O). Considering 'g' to be a function from the non-negative integers to the positive real

Write Your Message!

Captcha
Order Assignment

Featured Services

Order Now

Popular Subjects

Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

Submit Assignment

Academics

Major Subjects

Majors

Get In Touch

whatsapp: +91-977-207-8620

Phone: +91-977-207-8620

Email: [email protected]

TERMS & POLICIES

HELP & SUPPORT

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd