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try it out 9-3
Run this application several times to understand how it works . Change the script
so that each bar will be drawn in a different color . Hint: Create a new list, named
color, for the Painter sprite that stores the color number of the five bars and use
the following command before drawing each bar:

numerical Lists

Lists of numbers appear in many practical applications. We can have lists of
test scores, temperature measurements, product prices, and more. In this
section, we’ll explore some common operations you might want to perform
on numerical lists. In particular, we’ll write procedures for finding the
maximum or minimum value and for finding the average of the numbers
stored in a list.

Finding Min and Max
FindMax .sb2 Suppose you’re a teacher and you need to know the highest score from
the last exam your class took. You could write a program to compare all of
those test scores and find the maximum value. Our first example, shown in
Figure 9-17, finds the highest number in a list named score.
The FindMax procedure starts by setting the value of the maxScore vari-
able equal to the first number in the list. It then starts a loop to compare
the remaining numbers in the list with the current value of maxScore. Every
time it finds a value greater than maxScore, it sets maxScore equal to that
value. When the loop terminates, the value stored in maxScore will be the
largest value contained in the list.

Assume that the first element in the list
is the maximum, until we discover
otherwise.
Start a loop to compare the remaining
numbers of the list (starting with the
second number) with maxScore.
Every time we find a value in the list
that is greater than maxScore, we set
maxScore equal to that value.

When the loop terminates, the value
stored in maxScore will be the largest
value contained in the list.
Figure 9-17: Finding the maximum number in a list

224 Chapter 9
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