User Manual
20060301
Modifying an Existing Program to Create a New One 
You can use the procedure described below to recall an existing program, modify it, and then 
run the result as a new program. This helps reduce key input requirements. 
The following shows how to modify the “OCTA” program we created on page 12-2-1 to 
handle tetrahedrons. 
Example:  To create a program named “TETRA” that calculates the surface areas (cm
2
) and 
volumes (cm
3
) of three regular tetrahedrons, the lengths of whose sides are 7, 10, 
and 15 cm 
The following formulas calculate the surface area S and volume V of a 
regular tetrahedron for which the length of one side A is known. 
The following is the program required for this example. 
Length of One Side A ..........Input A
Surface Area S ....................Print approx(
(3) 
s
 A^2)
Volume V ............................Print approx(
(2) 
w
 12 
s
 A^3)
The following is the “OCTA” program (page 12-2-1). 
Length of One Side A ..........Input A
Surface Area S ....................Print approx(2 
s
(3) 
s
 A^2)
Volume V ............................Print approx(
(2) 
w
 3 
s
 A^3)
A comparison of the two programs indicates that the following modifications of the “OCTA” 
program will produce a program that performs the calculations required by this example. 
• Delete “2
s
” (underlined with a wavy line above). 
• Change 3 to 12 (underlined with double lines above). 
S
 ClassPad Operation 
  (1) On the application menu, tap 
1
. 
 (2) Tap 
}
, or tap [Edit] and then [Open File]. 
12-3-2
Debugging a Program 
S = 
3 A
2
, V = 
2
12
 A
3
A










