Commodore Plus 4 - Getting to know the switches and sockets

4 The BASIC Language
example, if you assign 1.99 to X%, the value accepted fe*X% is 1.
part is truncated, not rounded.
Character string, or text string, variables can stand for My characters in
quotes, including numbers, blank spaces, and special symbols. The only key
board character that cannot be directly included in a character string is a
quotation mark. A number in quotation marks is treated like any text and has no
mathematical value.
Scientific Notation
Numbers can appear as simple numbers or in scientific notation. In scientific
notation, a number is reduced to its simplest one-whole-digit form. The number
of missing digits is shown in the exponent. The format for representing numbers
in scientific notation is as follows:
mantissa E sign exponent
The mantissa is a floating-point number with one whole digit (e.g., 1.55). The
E, which is the operator for scientific notation, stands for times 10 raised to the
following power. The sign is a negative or, positive sign; it indicates whether the
exponent is negative or positive. The exponent is the absolute value of the power
to which the number 10 is raised. This is always a whole number.
Both the mantissa and the exponent can be positive or negative numbers. The
following examples show how the signs of each number affect the value of the
number being represented.
Mantissa Exponent Number Example
Positive
Positive
Negative
Negative
Positive
Negative
Positive
Negative
Positive
Positive fraction
Negative
Negative fraction
1E+03
1E-03
-1E+03
-1E-03
= 1000
= .001
= -1000
= -.001
BASIC automatically displays numbers with absolute value smaller than .01 or
higher than 999999999 in scientific notation. If you enter a number outside this
range without typing it in scientific notation, BASIC rounds the number. This
rounding can cause a slightly inaccurate result if the number is used in a calcula
tion. To avoid this distortion, always enter small or large numbers in scientific
notation. In any case, BASIC can keep track of only about nine decimal digits in
the mantissa.