Lesson #11 Average Sales - Radio Shack TRS-80 Model 100 Basic Manual

Lesson #11 Average Sales
In this lesson you will learn how to compute the average daily sales using the data you
stored in RAM in the last Lesson under the name SALEDA.DO.
Arrays with two dimensions will be used so that the data can be examined on a daily
or weekly basis. You will learn how to sort an array so that the median can be
calculated. Subroutines will be used to avoid repetitive blocks of code in your
programs. The TAB statement will be used to space the output neatly.
Experiment #1 Display the File
The following program will read 6 weeks of daily sales values from file SALEDA.DO
in RAM and display the values.
Clear working memory and enter the following program:
5 OPEN "RAM:SALEDA.DO" FOR INPUT AS 1
10
FOR W = 1 TO 8
:
FOR D = 1 TO 5
20 INPUT
#
1 t S<WtD)
30
NEXT D
.
NEXT W
.
1I0 PRINT "WEEK MON TUE WED
THU FRI"
50 FOR W = 1 TO 8 PRINT W;
80 FOR D=1 TO 5
70 PRINT TA6(D*5) S<WtD);
80 NEXT D : PRINT
80 NEXT W
Execute this program.
The program will read the file SALEDA.DO containing sales data.
The following table will then be output to the LCD:
WEEK MON TUE WED THU FRI
1
280 275 3£18 280 250
2 300
280 320 300 242
3 282 270
350 310 255
4 310 250 310 280 280
5 280 280 280 280 270
8
285 280 330 275 258
Line 5 The OPEN statement opens the RAM data file "SALEDA.DO" for input and
assigns the file number I to it.
Line
H~
The first FOR statement,
FOR W = 1 TO 8
sets up an outer loop to index through the six weeks. The second FOR statement
FOR D = 1 TO 5
sets up an inner loop to index through the five days of the week.
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