Difference between revisions of "Category:Variables"
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There are a few types of variables. Most store numbers, but the special [[Reference Variables]] stores | There are a few types of variables. Most store numbers, but the special [[Reference Variables]] stores pointers to objects in the game world so you can run functions on it later. | ||
Although you can [[Declaring_variables|declare a variable]] to be [[Short Integer|Short]], [[Long Integer|Long]], or [[Floating Point|Float]], | Although you can [[Declaring_variables|declare a variable]] to be [[Short Integer|Short]] or [[Long Integer|Long]], both will be stored as [[Long Integer|Long]] when they're declared as local variables in scripts. (i.e. you can't save memory by using short instead of long). | ||
[[Globals]], though, no matter whether declared as [[Short Integer|Short]], [[Long Integer|Long]] or [[Floating Point|Float]], will always be stored like a [[Floating Point|float]]. | |||
This is significant, as [[Floating Point|floats]] have accuracy issues at very high or very low values. When dealing with [[Short Integer|shorts]], this is irrelevant as their range is within the float's "accurate" range. On the other hand, [[Long Integer|longs]] may be expected to be accurate outside of the [[Floating Point|float]]'s range, and they will not be. | This is significant, as [[Floating Point|floats]] have accuracy issues at very high or very low values. When dealing with [[Short Integer|shorts]], this is irrelevant as their range is within the float's "accurate" range. On the other hand, [[Long Integer|longs]] may be expected to be accurate outside of the [[Floating Point|float]]'s range, and they will not be. | ||
To illustrate, the sizes of numbers that should be storable in each type: | To illustrate, the sizes of numbers that should be storable in each type: | ||
Revision as of 12:23, 28 February 2011
This category has been marked by editors as one needing attention. Please see the Talk page for details. If you can update the category, please do so.
There are a few types of variables. Most store numbers, but the special Reference Variables stores pointers to objects in the game world so you can run functions on it later.
Although you can declare a variable to be Short or Long, both will be stored as Long when they're declared as local variables in scripts. (i.e. you can't save memory by using short instead of long).
Globals, though, no matter whether declared as Short, Long or Float, will always be stored like a float.
This is significant, as floats have accuracy issues at very high or very low values. When dealing with shorts, this is irrelevant as their range is within the float's "accurate" range. On the other hand, longs may be expected to be accurate outside of the float's range, and they will not be.
To illustrate, the sizes of numbers that should be storable in each type:
short -32,768 to 32,767 long -2,147,483,648 to 2,147,483,647 float 1.18E-38 to 3.40E38 (precision = 7 digits)
As you can see, a long might be expected to have up to 10 digits, but a float will not accurately display more than 7 (it can, however, accurately show a number of less than eight digits followed by twenty or more zeros, if necessary), and so a long will not behave as expected because it is actually a float. See the float article for more information on floats' accuracy, and see Long's Talk page for details on this discovery.
Other than that, however, generally longs and shorts will be rounded off to the nearest integer (i.e. 1.25 becomes 1, 1.75 becomes 2), while floats will store the decimal data. However, if a variable is a Global, then it will always be a float and therefore will not round off the decimal values.
See Also
Pages in category "Variables"
The following 8 pages are in this category, out of 8 total.