Chelsea Troy chelseatroy

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chelseatroy / representing_data_structures.scm

Last active October 29, 2019 21:54

Representing Data Structures

	; 2.2 Representing data with procedures

	(define (make-point x y)(cons x y))
	(define (x-point point) (car point))
	(define (y-point point) (cdr point))

	(define a-point (make-point 0 0))
	(define b-point (make-point 2 2))
	(x-point a-point)
	(y-point a-point)

chelseatroy / list_reversal.scm

Last active October 29, 2019 22:02

List Reversal

	; 2.18

	(define (reverse list)
	(define (iter-list reversed-list unprocessed-remaining)
	(if (null? unprocessed-remaining)
	reversed-list
	(iter-list (cons(car unprocessed-remaining) reversed-list) (cdr unprocessed-remaining))
	)
	)
	(iter-list null list))

chelseatroy / parity_function.scm

Last active October 29, 2019 22:04

Parity Function

	; 2.20

	(define (same-parity first . remaining)
	(define (iter-list parity-list unprocessed-remaining)
	(if (null? unprocessed-remaining)
	parity-list
	(if (= (remainder first 2) (remainder (car unprocessed-remaining) 2))
	(iter-list (cons(car unprocessed-remaining) parity-list) (cdr unprocessed-remaining))
	(iter-list parity-list (cdr unprocessed-remaining)))
	)

chelseatroy / mapping.scm

Last active October 29, 2019 22:06

Mapping

	; 2.21

	(define (square-list1 items)
	(if (null? items)
	null
	(cons (* (car items) (car items)) (square-list1 (cdr items)))
	)
	)

	(define (square-list2 items)

chelseatroy / append_cons_list.scm

Created October 29, 2019 22:06

Append, Cons, and List

chelseatroy / reverse_parity_list.scm

Created October 29, 2019 22:07

Reversing the Parity List

	; 2.20

	(define (same-parity first . remaining)
	(define (iter-list parity-list unprocessed-remaining)
	(if (null? unprocessed-remaining)
	parity-list
	(if (= (remainder first 2) (remainder (car unprocessed-remaining) 2))
	(iter-list (cons(car unprocessed-remaining) parity-list) (cdr unprocessed-remaining))
	(iter-list parity-list (cdr unprocessed-remaining)))
	)

chelseatroy / deep_reverse.scm

Last active October 29, 2019 22:44

Deep Reverse

	; 2.27

	(define (deep-reverse list)
	(define (iter-list reversed-list unprocessed-remaining)
	(if (null? unprocessed-remaining)
	reversed-list
	(iter-list (cons (if (list? (car unprocessed-remaining))
	(deep-reverse (car unprocessed-remaining))
	(car unprocessed-remaining))
	reversed-list) (cdr unprocessed-remaining))

chelseatroy / data_as_procedures.scm

Last active November 2, 2019 20:53

Data Represented as Procedures

	; 2.2 Representing data with procedures

	(define (make-point x y)(cons x y))
	(define (x-point point) (car point))
	(define (y-point point) (cdr point))

	(define a-point (make-point 0 0))
	(define b-point (make-point 2 2))
	(x-point a-point)
	(y-point a-point)

chelseatroy / data_as_procedures.scm

Last active November 2, 2019 21:02

Making Data out of Procedures

	; 2.4: Representing data AS procedures

	(define (2.4-cons x y)
	(lambda (m) (m x y)))

	(define (2.4-car z)
	(z (lambda (p q) p)))

	(define (2.4-cdr z)
	(z (lambda (p q) q)))

chelseatroy / data_as_procedures.scm

Last active November 2, 2019 21:15

Data Represented as a Different Procedure