Another common operation is the use of boolean vectors to filter the data. The operators are: | for or, & for and, and ~ for not. These must be grouped by using parentheses, since by default Python will evaluate an expression such as df.A > 2 & df.B < 3 as df.A > (2 & df.B) < 3, while the desired evaluation order is (df.A > 2) & (df.B < 3).

Sep 19, 2012 · Also like arithmetic operators, logical operators have precedence that determines how things are grouped in the absence of parentheses. In an expression, the operator with the highest precedence is grouped with its operand(s) first, then the next highest operator will be grouped with its operands, and so on.

From wikipedia on boolean logic: In such cases [of ambiguity], parentheses may be used to clarify the order of operations. As always, the operations within the innermost pair is performed first, followed by the next pair out, etc., until all operations within parentheses have been completed.

@flow2k The reason is that bitwise or has higher precedence than the comparison operators (that doesn't happen with the boolean or). For more information, please have a look at the documentation – jcollado

Sep 10, 2023 · But there is still something in Python which can mislead you: The result of and and or operators may be different from True or False - see 6.11 Boolean operations in the same document. Share Improve this answer

can anyone recommend software (preferably for mac) or a web based tool, that can be used to evaluate logic expressions? For example I would like to be able to quickly test whether two expressions ...

Feb 12, 2013 · The implicit conversion is why your 2 gets promoted to a Float, not because of your boolean logic. I don't think your operators and implicits method is the best solution to this sort of problem. There are many ways to write concise elegant scala code using Options, filter, exists, map, flatMap, etc, that can handle the kinds of operations you ...

May 29, 2013 · In the normal set of boolean connectives (from a logic standpoint), and is higher-precedence than or, so A or B and C is really A or (B and C). Wikipedia lists them in-order. Most programming languages should obey this convention unless they are really weird.

Dec 8, 2013 · -a and -o are the older and/or operators for the test command. && and || are and/or operators for the shell. So (assuming an old shell) in your first case, [ "$1" = 'yes' ] && [ -r $2.txt ] The shell is evaluating the and condition. In your second case, [ "$1" = 'yes' -a $2 -lt 3 ]

Nov 23, 2020 · The and and or keywords serve the same purpose in Ruby. Properly understood, and and or are control flow operators, not boolean operators. You use them as more like control-flow operators if, unless. This operations have very low operator precedence. Further reading: and or and short-curcuit difference short-curcuit