What is the Difference Between D and E in Scientific Notation?

AI Thread Summary
The distinction between 6.6725985D-20 and 6.6725985E-20 lies in their representation of numerical precision in programming, with 'D' indicating double precision and 'E' indicating single precision. This notation is particularly relevant in languages like Fortran, but may also apply to others. For non-programmers, both notations can be considered equivalent without concern for precision. In Visual Basic, the editor automatically converts 'D' to 'E' based on the precision defined in the Dim statement. Understanding these differences is essential for programmers dealing with numerical data types.
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What's the difference between:

6.6725985D-20

and

6.6725985E-20
 
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From a computer programming point of view the D means the number is stored as double precision where as E is stored as single precision (for exmaple this is the notiation used in the fortran programming language, but it may apply to other languages, I am not sure). If you arent doing any programming but just came across this then you shouldn't need to worry about it and yo ucan assume that the two are equivalent. If you are programming then do some googling/reading on single/double precision etc.
 
Thanks. That makes sense. I was wondering in relation to VB. I just tried it, and the VB editor automatically changes D to E, with the precision set in the Dim statement.
 

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