When a format is not
specified for writing a numeric value, SAS uses the BEST
w.
format as the default format. The BEST
w.
format attempts to write numbers that balance the conflicting requirements
of readability, precision, and brevity. Here are several rules:
-
Values are written with the maximum
readable precision, as determined by the width. The maximum precision
for floating-point numbers might be limited to 14 or 15 digits, as
determined by the width.
-
Integers are written without decimals.
-
Numbers with decimals are written
with as many digits to the left and right of the decimal point as
needed or as allowed by the width.
-
Extreme values and values with
leading or trailing zeros might be written in scientific notation
to fit into the specified width, to increase the precision, or to
simplify the magnitude of the number. Extremely small values might
be written as 0 if the width is too small for scientific notation.
-
Trailing zeros are not written.
-
If a value cannot be represented
in either decimal or scientific notation in the width that is specified,
the output field is filled with asterisks.
-
The behavior of the BEST
w.
format is affected by the setting of the DECIMALCONV option.
For more information,
see DECIMALCONV= System Option in SAS System Options: Reference. These rules are generally applicable regardless of the
option setting.