boolean-logic

问题 Every time one of these questions comes up in my assignments I get it wrong...can anyone help me understand? Or is the teacher's key off? (There is no way for me to know as I'm not given the correct answer, it only lets me know that mine is wrong.) Assume x = 7 and y = 5 . Applying De Morgan's Law, select the logical expression below that is equivalent to the following logical expression: !(x>5)||!(y>7) (a) !(x>5)&&!(y>7) (b) !((x>5)||(y>7)) (c) !(x>5)&&(y>7) (d) (x>5)||!(y>7) (e) None of the

问题 I have two DataFrames where each column contain True/False statements. I am looking for a way to test all possible combinations and find out where "True" for each row in df1 also is "True" in the corresponding row in df2. In reference to the data below, the logic would be something like this: For each row, starting in column "Main1", test if row is equal to True and if row in column "Sub1" also is True. Next, test if row in "Main1" is equal to true and if rows in column "Sub1" is True and

问题 How can I know if two boolean expresions are equivalent? String expr1 = "(A or B) and C"; String expr2 = "C and (B or A)"; boolean equals = areExprsEquals(expr1, expr2); I think I should... Parse the expresion storing it in some structure data Reduce the expresion in OR groups Check if the two expresions have the same groups For example, with the step two I get: Expr1 (A or B) and C Converted to: (A and C) or (B and C) Expr2 C and (B or A) Converted to: (C and B) or (C and A) Now I have to

问题 How can I know if two boolean expresions are equivalent? String expr1 = "(A or B) and C"; String expr2 = "C and (B or A)"; boolean equals = areExprsEquals(expr1, expr2); I think I should... Parse the expresion storing it in some structure data Reduce the expresion in OR groups Check if the two expresions have the same groups For example, with the step two I get: Expr1 (A or B) and C Converted to: (A and C) or (B and C) Expr2 C and (B or A) Converted to: (C and B) or (C and A) Now I have to

问题 I have many truth-tables of many variables (7 or more) and I use a tool (eg logic friday 1) to simplify the logic formula. I could do that by hand but that is much too error prone. These formula I then translate to compiler intrinsics (eg _mm_xor_epi32) which works fine. Question : with vpternlog I can make ternary logic operations. But I'm not aware of a method to simplify my truth-tables to sequences of vpternlog instructions that are (somewhat) efficient. I'm not asking if someone knows a

问题 I am currently in the course of learning Python 2.7 and have come across the Equality and Boolean operators My question is: Why False and 1 is False but True and 1 is 1 Likewise, False or 1 is 1 but True or 1 is True Can someone kindly explain why this is happening Many thanks 回答1: and returns the first 'falsy' (False, zero, empty string or list, etc.) value it sees, or the final value if none were falsy. Further values are not even evaluated, since they can't change the result. or likewise

问题 I want to make a condition where all selected variables are not equal. My solution so far is to compare every pair which doesn't scale well: if A!=B and A!=C and B!=C: I want to do the same check for multiple variables, say five or more, and it gets quite confusing with that many. What can I do to make it simpler? 回答1: Create a set and check whether the number of elements in the set is the same as the number of variables in the list that you passed into it: >>> variables = [a, b, c, d, e] >>>

问题 return a or b or c or d; That statement returns either true or false in C++, and I know the reason for this. But I need a workaround so that I can return the first non-zero value via that return statement (or something similar) like it happens in Python . I am not looking for conditional statements as it looks untidy sometimes. Basically, can the following code be shortened via a macro or something else? int fun(int a, int b, int c, int d) { return a ? a : b ? b : c ? c : d; } 回答1: I would

问题 Since this is (at least it seems to me) tightly related to programming, I'm asking here rather than on math or cs, but if you it think it best fits there or in another side, please just give your opinion. At the end of Chapter 2 of Bartosz Milewski's Category Theory for Programmers , there's this question: How many different functions are there from Bool to Bool ? Can you implement them all? This is my reasoning: Bool has only two elements in it, True and False ; different refers to what the

问题 I have code like that: optionBoolean.getOrElse(false) && otherOptionBoolean.getOrElse(false) And Scalastyle tells me that it can be simplified. How? 回答1: You can try the following: Seq(optionBoolean, otherOptionBoolean).forall(_.contains(true)) In Scala 2.13 (it is very similar in prior versions) the forall method is located at IterableOnce, and its implementation is: def forall(p: A => Boolean): Boolean = { var res = true val it = iterator while (res && it.hasNext) res = p(it.next()) res }