I am curious about some details of work of logical operators in R.
For example, let we have following expression:
A == a & B == b & C == c & D == d &.... and so on.
If A == a gives FALSE, will R evaluate all following operators or will it stop and result FALSE at once?
Alexandr Pozharskiy
Since 0 is often associated with “Off“ or “False” and 1 with “On” or “True”, R decides to allow 1 == TRUE and 0 == FALSE to both be true. Any other numeric-to-boolean comparison should yield false, unless it's something like 3 - 2 == TRUE. Hope this helps. Good luck with your work!
Alexandr Pozharskiy
Since 0 is often associated with “Off“ or “False” and 1 with “On” or “True”, R decides to allow 1 == TRUE and 0 == FALSE to both be true. Any other numeric-to-boolean comparison should yield false, unless it's something like 3 - 2 == TRUE. Hope this helps. Good luck with your work!
It is not only important what to compare (although Giovane R Sousa makes a valid point) but also how to connect your boolean expressions.
By connecting them with the logical AND operator, R will always evaluate all individual boolean expressions and will only result in TRUE when all are boolean comparisons are a match. This is not a quirk, but the way formal coding works in general and consequently, you will find this in many other programming languages.
If you wish to do something else, like compare many values in vector you can do something like the following in R:
a
More correctly, R does what YOU ask it to do. Make sure you have coded your wish correctly. Best, D. Booth
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