.nr PS 11
.ps 11
.nr VS 13
.vs 13
.SH
.ce
EXAMPLE PROGRAM CIRCLE CALCULATION REPORT
.NH
Requirements
.LP
To produce a program that calculates the circumference and area of a
circle
given its radius. Assume "PI" is equivalent to 3.14 and that the radius
is input
by the user as a floating point number. Area of a circle = PI \(mu
diameter = 2 \(mu PI \(mu radius
and Volume = PI \(mu radius^2.
.NH
Design
.LP
A top down analysis is presented in Table 1.
.PS
a =
b =
c =
d =
e =
.vs
4.5/3
0.5
0.5/2
0.5
d/2
12
M:box invis wid
B1:box wid a ht
B2:box wid a ht
B3:box wid a ht
B4:box wid a ht
line from B1.s
line from B3.n
line from B1.s
.PE
.LP
.ce
.ps 15
\fBTable 1:\fI
6
b
b
b
b
ht b+d+b
with .n at M.n "Circle""calculation"
with .sw at M.sw +(0.5,0) "Input data"
with .s at M.s "Calculate and""output""circumference"
with .se at M.se -(0.5,0) "Calculate and""output area"
to B1.s -(0,e) to B2.n +(0,e) to B2.n
to B3.n +(0,e)
-(0,e) to B4.n +(0,e) to B4.n
Top down analysis\fR
.LP
These operations are simple enough to be wrapped up into a single
procedure:
.IP 1) 3
\fCCIRCLE_CALC\fR (top level procedure): Input radius, and calculate and
output circumference and area. Uses the following two data items.
.TS
box,center,tab($);
c | c | c | c
l | l | l | l.
NAME$DESCRIPTION$TYPE$VALUE/RANGE
=
PI$Global constant$FLOAT$3.14
RADIUS$Global input variable$FLOAT$Default
.TE
.LP
The detailed design for this procedure is given by the
Nassi-Shneiderman chart presented in Table 2.
.PS
a = 3
b = 0.3
M:box invis wid 6 ht b*3
box wid a ht b with .n at M.n "Input RADIUS"
box wid a ht b with .n at last box.s "Calculate and output circumference
"
box wid a ht b with .n at last box.s "Calculate and output area"
.PE
.ce
.ps 15
\fBTable 2:\fI Nassi-Shneiderman Chart\fR
.NH
Implementation
.LP
Implementation is as shown in Table 3.
.ft CW
.ps 10
.vs 11
.TS
center,box;
l.
-----
CIRCLE CALCULATION
15 August 1997
Frans Coenen
Dept Computer Science, University of Liverpool
with CS_IO;
use CS_IO;
procedure CIRCLE_CALC is
PI: constant FLOAT := 3.14;
RADIUS: FLOAT;
begin
PUT_LINE("Input radius: ");
GET(RADIUS);
-- Calculate circumference using 2xPIxRadius
PUT("The circumference is: ");
put(2.0*PI*RADIUS,FORE => 3,AFT=>4,EXP =>0);
NEW_LINE;
-- Calculate area using PIxRadius^2
PUT("The area is: ");
put(PI*RADIUS*RADIUS,FORE => 3,AFT=>4,EXP =>0);
NEW_LINE;
end CIRCLE_CALC;
.TE
.ce
.ps 15
\fBTable 3:\fI Implementation\fR
.NH
Testing
.LP
\fBArithmetic testing|fR: Test using positive, negative and zero input
values for \fCRadius\fR as shown in Table 4.
.ft CW
.TS
center,box,tab($);
c || c s
l || l | l.
TEST CASE$EXPECTED RESULT
_
RADIUS$CIRCUMFERENCE$AREA
=
10.0$62.8000$314.0000
0.0$0.0000$0.0000
-10.0$-62.8000$314.0000
.TE
.ce
.ps 15
\fBTable 4:\fI Test cases\fR
.LP
Note negative circumference?
A screen dump illustrating the output produced as a result of running the
above test cases is given in Table 5.
.ft CW
.ps 10
.vs 11
.TS
center,box;
l.
kuban-349 $ circle_calc
Input radius:
10.0
The circumference is:
The area is: 314.0000
62.8000
kuban-350 $ circle_calc
Input radius:
0.0
The circumference is:
0.0000
The area is:
0.0000
kuban-351 $ circle_calc
Input radius:
-10.0
The circumference is: -62.8000
The area is: 314.0000
.TE
.ce
.ps 15
\fBTable 5:\fI Arithmetic test output\fR
.LP
\fBData validation testing\fR: Test input with wrong type and too many
inputs. Result shown in Table 6.
.ft CW
.ps 10
.vs 11
.TS
center,box;
l.
kuban-289 $ circle_calc
Input radius:
x
Ada-runtime: Exception
FLOAT_INPUT_ERROR_DIGIT_NOT_READ
propagated out of main.
kuban-290 $ circle_calc
Input radius:
5.0 10.0
The circumference is: 31.4000
The area is: 78.5000
kuban-291 $ 10.0
ksh: 10.0: not found
.TE
.ce
.ps 15
\fBTable 6:\fI Data validation test output\fR