The range of valid numbers for a floating point literal is 16 places. This is the total number of places, on both sides of the decimal point. ESL ignores numbers beyond the 16th place. Double precision is not allowed.

Note that because of the number of digits of precision stored in the computer for float numbers, float numbers that appear to be equal may not always yield a true result when comparisons are made.

When you specify a floating point literal, you can specify minus signs and leading zeros in front of the decimal point. The following are valid floating point literals:

 

0.01

-.5          # The leading zero is understood.

.0103

-9999.01

 

All other characters are invalid, including scientific notations, embedded blanks, and commas. The following are not valid floating point literals:

 

3,942,885.03    # WRONG: contains commas

.05E7           # WRONG: contains an alphabetic character

.02 3           # WRONG: contains an embedded blank

 

A floating point literal can be specified in any context in which a floating point value is required; for example:

 

float constant Rate is 9.895

 

A comparison of two floating point values is actually a comparison of an approximation of two values.