Medium-sized application: generic sorting and a database

3rd CCSC Northwest Conference • Fall 2001

Medium-sized application: generic sorting and a database

Simple insertion and quicksorts

standard sorting algorithms such as insertion sort or quicksort can be written in a few lines; some trade-offs between abstraction and readability are demonstrated here for quicksort

3rd CCSC Northwest Conference • Fall 2001

Medium-sized application: generic sorting and a database

Simple insertion and quicksorts

Generalizing to an arbitrary order relation

using higher-order functions we can easily generalize our quicksort to work for arbitrary ordering relations

3rd CCSC Northwest Conference • Fall 2001

Medium-sized application: generic sorting and a database

Simple insertion and quicksorts

Generalizing to an arbitrary order relation

Sorting on extracted "fields"

now, given some more structured data, we can succinctly express sorts by different criteria

3rd CCSC Northwest Conference • Fall 2001

Medium-sized application: generic sorting and a database

Simple insertion and quicksorts

Generalizing to an arbitrary order relation

Sorting on extracted "fields"

Simultaneous sorting

we can even extend our sorting function to use two relations on the same data, thus providing independent simultaneous sorts

3rd CCSC Northwest Conference • Fall 2001

Medium-sized application: generic sorting and a database

Simple insertion and quicksorts

Generalizing to an arbitrary order relation

Sorting on extracted "fields"

Simultaneous sorting

A simple academic course database

a type definition and a few utility functions provide us with a simple database of academic courses

3rd CCSC Northwest Conference • Fall 2001

Medium-sized application: generic sorting and a database

Simple insertion and quicksorts

Generalizing to an arbitrary order relation

Sorting on extracted "fields"

Simultaneous sorting

A simple academic course database

Derived lexicographic orderings

a little bit of logical manipulation allows us to extend any pair (or list) of ordering relations to provide a lexicographic sort

	Simple insertion and quicksorts
	Generalizing to an arbitrary order relation using higher-order functions we can easily generalize our quicksort to work for arbitrary ordering relations

	Simple insertion and quicksorts
	Generalizing to an arbitrary order relation
	Sorting on extracted "fields" now, given some more structured data, we can succinctly express sorts by different criteria

	Simple insertion and quicksorts
	Generalizing to an arbitrary order relation
	Sorting on extracted "fields"
	Simultaneous sorting we can even extend our sorting function to use two relations on the same data, thus providing independent simultaneous sorts