Radio Shack TRS-80 Model 100 Basic Manual page 46

Line 40 is another INPUT statement. This time, however, you are expected to enter a
name instead of a number. The name which you enter is stored in the variable N$.
This variable, N$, is an example of a "string variable." The name that you type, for
example., JANICE SMITH, is called a "character string."
Line
58
calculates the total of principal and interest.
Line
60
prints the message "TOTAL FOR."
Line
65
prints the name stored in N$ followed by the word IS, the symbol
$,
and the
amount of the investment.
Line
70
skips a line (PRINTs a blank line).
Line
80
transfers control back to line 10.
A string is any sequence of keyboard characters, for example
JOHN SMITH
1023 N. MAIN STREET
1982
MACROCORP
MARCH 12, 1984
$120.95
In some cases the string may consist entirely of digits (e.g. 1982), but it can still be
considered a string as well as a numerical constant.
A valid string variable is any numeric variable followed by a dollar sign
($).
The
following are all valid examples of string variables:
N$, A3$, DA$, AD$, ST$
In line 40, it is essential that the variable
be a string variable. If you tried to use a
numeric variable, the computer would continue to ask for data until a numeric constant
was entered.
The assignment of the name to the string variable N$ was made with the INPUT
statement. It is possible to use assignment statements with string variables and
constants just as with numeric variables and constants. For example, the following
statement:
11Z11Z1 A$
=
"RADIO SHACK"
assigns the string RADIO SHACK to the string variable A$. When using an
assignment statement, it is necessary to enclose the string in quotes, as shown above.
Each string variable can hold up to 256 characters. If the total number of characters
assigned to string variables exceeds 256, you must set aside additional space. This is
done with the CLEAR statement. For example, the following line could be added to
the program:
5 CLEAR 31Z11Z1
This particular instruction allocates space for 300 characters. If you attempt to store
more than 300 characters in N$, an error will result and the program will terminate.
When the Computer is turned on, space for 256 characters is allocated automatically.
40