This lab is also available in PDF.
Summary: In this lab, we explore a variety of issues related to the insertion sort algorithm.
a. Start DrScheme.
b. Copy the code from the accompanying reading into DrScheme.
a. Test both versions of the
insert-number procedure from
the reading by inserting the number 42
(list 42 42 42).
b. What happens if the list is not in ascending order when
insert-number is invoked?
Write a new
insert-string procedure that inserts a string into a
list of strings that are in alphabetical order:
> (insert-string "dog" (list "ape" "bear" "cat" "emu" "frog")) ("ape" "bear" "cat" "dog" "emu" "frog")
In case you've forgotten,
string-ci<=? are useful predicates for comparing
strings for order.
You may not use the generalized
insert procedure in
writing this procedure.
a. Show how to call the generalized
insert procedure using
lists of strings.
b. Show how to call the generalized
insert procedure using
lists of numbers.
insert-string so that it uses
insert as a helper procedure.
a. Add calls to the
newline procedures to the body of the helper in
insertion-sort-numbers so that it displays the values of
sorted, appropriately labeled,
at each step of the sorting process.
b. Use the revised
procedure to sort the values 7, 6, 12, 4, 10, 8, 5, and 1.
Write a test suite (using
unit-test.scm) to test the
insertion-sort-numbers procedure on some potentially
(load "/home/rebelsky/Web/Courses/CS151/2007S/Examples/unit-test.ss") (begin-tests!) ... (end-tests!)
a. An empty list
b. A list containing only one element
c. A list containing all equal values
d. A list in which the elements are originally in descending numerical order
Document, write, and test a procedure,
(insertion-sort list may-precede?).
that generalizes the
a. Make a copy of the
insert! procedure from
b. Check that it works by using
insert! to put the 2 in
the correct place in the following vector
(define numbers (vector 1 5 6 7 2 8 0 3))
(Note that solving this step requires that you understand the parameters to
insert! so that it displays the vector and the
position at every step. (Add calls to
newline in the kernel, before the
d. Create the numbers vector from step b, and observe what happens when we insert the 2, then the 8, then the 0, then the 3.
e. Make a copy of the
insertion-sort! procedure from
f. Observe the insertion steps in a list of about eight randomly-generated numbers.
(define nums (vector (random 10) (random 10) (random 10) (random 10) (random 10) (random 10) (random 10) (random 10)))
I usually create these pages
on the fly, which means that I rarely
proofread them and they may contain bad grammar and incorrect details.
It also means that I tend to update them regularly (see the history for
more details). Feel free to contact me with any suggestions for changes.
This document was generated by
Siteweaver on Thu Sep 13 20:54:20 2007.
The source to the document was last modified on Sun Apr 22 21:38:01 2007.
This document may be found at
You may wish to validate this document's HTML ; ;Samuel A. Rebelsky, email@example.com
http://creativecommons.org/licenses/by-nc/2.5/or send a letter to Creative Commons, 543 Howard Street, 5th Floor, San Francisco, California, 94105, USA.