lecture 4 (Unfinished)

Question 1

Why Sorting?

Answer 1

Sorting is one of the most common tasks in data analysis.

Question 2

What is Selection sort?

Answer 2

The Selection Sort algorithm repeatedly finds the smallest element in the unsorted tail region of a list and moves it to the front
Big O -n^2

Question 3

What is a Linear Search?

Answer 3

The list is traversed sequentially, and every element is checked#

List does NOT need to be sorted

Big-O: O(n)

Question 4

What is a Binary Search?

Answer 4

A ‘divide and conquer algorithm
The list MUST be sorted

Big-O: O(log2(n))

Question 5

How do you conduct a Binary Search?

Answer 5

1) find the middle element- if a match then were done

2) if the key is less the middle element the key must be in the first half (opposite if key bigger)

Question 6

Binary Search vs Linear Search

Answer 6

Binary search algorithm is much faster, But it only works on sorted data.

Big-O of O(log2(n))

If Binary Search is used with selection sort then Linear Search is faster

Question 7

What is Algorithm Complexity?

Answer 7

Algorithmic complexity tells us how slow or fast an algorithm performs

T(n) will be used to denote the time an algorithm takes to execute – time versus input size n

Question 8

How do you perform asymptotic analysis?

Answer 8

We find the worst-case number of primitive operations executed as a function of the input size, T(n)
We express this function with Big-Oh notation