boolean

问题 Do they have a reason for doing so? I mean, in the sum of minterms, you look for the terms with the output 1; I don't get why they call it "minterms." Why not maxterms because 1 is well bigger than 0? Is there a reason behind this that I don't know? Or should I just accept it without asking why? 回答1: The convention for calling these terms "minterms" and "maxterms" does not correspond to 1 being greater than 0. I think the best way to answer is with an example: Say that you have a circuit and

问题 I want to do a select in MySql that combines several columns... something like this pseudocode: SELECT payment1_paid AND payment2_paid AS paid_in_full FROM denormalized_payments WHERE payment1_type = 'check'; Edit : payment1_paid and payment2_paid are booleans. I can't use any other language for this particular problem than MySql. Thanks for any help! Edit : Sorry to everybody who gave me suggestions for summing and concatenating, but I've voted those early answers up because they're useful

问题 I want to validate a string in C# that contains a Boolean expression with brackets. The string should only contain numbers 1-9, round brackets, "OR" , "AND". Examples of good strings: "1 AND 2" "2 OR 4" "4 AND (3 OR 5)" "2" And so on... I am not sure if Regular Expression are flexible enough for this task. Is there a nice short way of achieving this in C# ? 回答1: It's probably simpler to do this with a simple parser. But you can do this with .NET regex by using balancing groups and realizing

问题 I was reading something about boolean attribute here, which says that for a boolean attribute (in this particular example, loop attribute of <audio> ), whatever value you set, it is going to be recognized as "true". In order to really set to falsy, you cannot set it like loop=false or with javascript as ['loop']=false , but have to remove the attribute such as by doing removeAttribute('loop') . Is this true? I first believed it, but as far as checked it with Chrome, it seems that setting to [

问题 It appears that in iOS I have a number of options that seem to fit for boolean values: YES NO TRUE FALSE true false Which ones should I use? In this particular case I'm hiding a label, so should I set the hidden property to YES , TRUE , or true ? 回答1: Short answer: you should prefer YES and NO for setting foundation properties of type BOOL . For the long answer, let's first see where are these constants defined: true and false are from stdbool.h; they are #define -d as 1 and 0 TRUE and FALSE

问题 I am looking for a way to evaluate a Swift Bool concisely in a single if statement, when the Bool is the property of an optional object: var objectWithBool: ClassWithBool? // ... if let obj = objectWithBool { if obj.bool { // bool == true } else { // bool == false } } else { // objectWithBool == nil } Is there are way to combine these if statements? In Objective-C this could easily be done, as a nil object can be evaluated in the same expression: if (objectWithBool.bool) { // bool == true }

问题 Which of the following declarations conforms to Java's naming conventions? private boolean writerIsEnabled; // with methods like public boolean getWriterIsEnabled() public void setWriterIsEnabled() OR private boolean writerEnabled; // with methods like public boolean getWriterEnabled() public void setWriterEnabled() I personally find the first name "writerIsEnabled" to be more readable, especially when you use it in an if statement like this - if(writerIsEnabled) { //... } 回答1: As far as I

问题 I'm new to Python and while trying Python logical statements.I came across this which I'm not able to understand.Can anyone tell me whats happening here in Python 2.7.Whats the difference between 0 and False value in Python. >>> 0 or False False >>> False or 0 0 Why the interpreter is giving different answers ? 回答1: You are being confused by the behaviour of the or operator; it returns the first expression that only if it is a true value; neither 0 nor False is true so the second value is

问题 I'm reading back a bit value from an SQL table, and casting as a boolean value to map to a boolean model value. But when I read back the IsPDLChecked bit field and initialise as false, I get an index out of range exception . I looked up the definition of the exception and I'm not sure why the value is out of range due to it being init with a false value , ie, 0 . So it's not a negative range value. Question: Why am I getting an IndexOutOfRange exception although the bit value being read back

问题 I'm trying to write a program that requires the calculation of a specific value dealing with Boolean functions. Given a single-output Boolean function f, given by a cover F, let's say I define the density of the function as the fraction of all input vectors where the function has the value 1. For example, suppose I pass in the given function f(a, b, c) which is defined by cover F = ab'+c'. The function has 5 ON-set minterms, and 8 total minterms, hence its density is d(f) = 5/8 = 0.625. It