comparison

问题 Okay so I managed to work out this code somehow with help from many of the coding experts here. I need to create a macro that compares data in two worksheets. In both of my worksheets, there is a column named "eRequest ID", I have to copy the rows of records that DO NOT have an "eRequest ID" in BOTH FILES . The code i worked out now copies recrods that have an "eRequest ID" in EITHER FILES . So logically speaking i have to "negate" the IF condition in my code below, but I have no idea how to

问题 Could you tell me why is the following condition false? List<Image> SelectedImages = new List<Image>(); SelectedImages.Add(Properties.Resources.my_image); if (SelectedImages[0] == Properties.Resources.my_image) // false { ... } Even if I write: SelectedImages[0] = Properties.Resources.my_image; if (SelectedImages[0] == Properties.Resources.my_image) // false { ... } How can I make this comparison work? 回答1: They're not equal because Properties.Resources makes a copy of the image and returns

问题 While looking at one issue related to sorting, I came across interesting difference for non alpha numeric characters comparison between string localeCompare method and conditional operator (like >,< ). You can see difference between them by running below snippets in different browsers. function comparison1(param1, param2){ return param1 > param2; } function comparison2(param1, param2){ return param1.localeCompare(param2); } document.getElementById("comparison11").innerHTML = comparison1('A',

问题 I have a list that contains a lot of sublists. i.e. mylst = [[1, 343, 407, 433, 27], [1, 344, 413, 744, 302], [1, 344, 500, 600, 100], [1, 344, 752, 1114, 363], [1, 345, 755, 922, 168], [2, 345, 188, 1093, 906], [2, 346, 4, 950, 947], [2, 346, 953, 995, 43], [3, 346, 967, 1084, 118], [3, 347, 4, 951, 948], [3, 347, 1053, 1086, 34], [3, 349, 1049, 1125, 77], [3, 349, 1004, 1124, 120], [3, 350, 185, 986, 802], [3, 352, 1018, 1055, 38]] I want to start categorizing this list firstly and making

问题 I'm trying to write an instance method for a Card class that compares a single card against an array. The class has some properties like: shape and color . The otherCards array is filled with other instances of this class, that also have their shape s and color s. Now, I want to write a method that can check all of these attributes separately. How can I pass in a particular attribute, as in: [allAttributesIsEqual:otherCards compareWith: self.shape] ? So I can pass in self.shape or self.color

问题 I'm working on a feature which requires me to get the contents of a webpage, then check to see if certain text is present in that page. It's a backlink checking tool. The problem is this - the function runs perfectly most of the time, but occasionally, it flags a page for not having a link when the link is clearly there. I've tracked it down to the point of visually comparing the strings in the output, and they match just fine, but using the == operator, php tells me they don't match.

问题 The discussion started under my answer to another question. The following code determines machine epsilon : float compute_eps() { float eps = 1.0f; while (1.0f + eps != 1.0f) eps /= 2.0f; return eps; } In the comments it was proposed that the 1.0f + eps != 1.0f test might fail because C++ standard permits the use of extra precision. Although I'm aware that floating-point operations are actually performed in higher precision (than specified by the actual types used), I happen to disagree with

问题 This question already has answers here : The order of expressions in an if statement [duplicate] (4 answers) Closed 3 years ago . Is there a specific reason why I have seen many people writing if(1 === a) {...} instead of if(a === 1) {...} I had given an answer in which I wrote something like Array === obj.constructor which is when someone asked me that he has often seen people writing like this instead of obj.constructor === Array . So does it really matter which way I use? 回答1: It's yoda

问题 Initially this may seem overly abstract or philosophical, but I am genuinely interested to see if someone has a convincing argument in favor of one implementation over the other. Given operator< for std::pair<T1, T2> , which would be the better implementation: return x.first < y.first || x.first == y.first && x.second < y.second; or: return x.first < y.first || !(y.first < x.first) && x.second < y.second; My understanding is that the two implementations yield equivalent results. Is the latter

问题 Initially this may seem overly abstract or philosophical, but I am genuinely interested to see if someone has a convincing argument in favor of one implementation over the other. Given operator< for std::pair<T1, T2> , which would be the better implementation: return x.first < y.first || x.first == y.first && x.second < y.second; or: return x.first < y.first || !(y.first < x.first) && x.second < y.second; My understanding is that the two implementations yield equivalent results. Is the latter