infinity

问题 alert(1/0) alerts Infinity and alert(1/-0) alerts -Infinity . alert(-1/-0) alerts Infinity , as I could expect when doing some operations with real numbers. I can't say that infinity is a measurable value. Does javascript think it is some number? 回答1: Yes, Infinity and -Infinity are special values of the Number type. From the ES5 spec: There are two other special values, called positive Infinity and negative Infinity. For brevity, these values are also referred to for expository purposes by

问题 I have an int a that needs to be equal to "infinity". This means that if int b = anyValue; a>b is always true. Is there any feature of C++ that could make this possible? 回答1: Integers are inherently finite. The closest you can get is by setting a to int 's maximum value: #include <limits> // ... int a = std::numeric_limits<int>::max(); Which would be 2^31 - 1 (or 2 147 483 647 ) if int is 32 bits wide on your implementation. If you really need infinity, use a floating point number type, like

问题 Closed . This question needs to be more focused. It is not currently accepting answers. Want to improve this question? Update the question so it focuses on one problem only by editing this post. Closed 5 years ago . Accidentally faced an Infinity property in JavaScript an wondered where in that world it can be used? Any real life example please. 回答1: I'm assuming you're asking about why there's an Infinity global property, not why there's a concept of having infinities in the first place,

问题 I am trying to find the right number of clusters, k , according to silhouette scores using sklearn.cluster.MiniBatchKMeans . from sklearn.cluster import MiniBatchKMeans from sklearn.feature_extraction.text import HashingVectorizer docs = ['hello monkey goodbye thank you', 'goodbye thank you hello', 'i am going home goodbye thanks', 'thank you very much sir', 'good golly i am going home finally'] vectorizer = HashingVectorizer() X = vectorizer.fit_transform(docs) for k in range(5): model =

问题 I'm trying to use numpy.multiply.outer on multidimensional arrays, and I really need it to assume that any 0 * infinity it sees evaluates to zero. How can I do this efficiently? >>> import numpy >>> numpy.multiply.outer([0.], [float('inf')]) Warning (from warnings module): File "__main__", line 2 RuntimeWarning: invalid value encountered in multiply array([[ nan]]) 回答1: Do you need to worry about other sources of nan values? If not, you could always just fix up in a separate step: import

问题 When working with (contentless) SpriteKit nodes I bumped into an infinite rectangle NSLog(@"%@", NSStringFromCGRect([node calculateAccumulatedFrame])); which outputted {{inf, inf}, {inf, inf}} I thought to check for this with CGRectIsInfinite , but that test failed, which lead me to trying the following check CGRect rect = [node calculateAccumulatedFrame]; if (rect.origin.x == INFINITY && rect.origin.y == INFINITY && rect.size.width == INFINITY && rect.size.height == INFINITY) { if (

问题 I was just curious, whether a number in JavaScript can ever reach Infinity . The range of JavaScript numbers is pretty good enough -- 2 to the power of 64 different numbers, which is about 18 Quintilian (an 18 with 18 zeros after it) . That’s a lot. Now, I've few questions here: What would really happen when a number grows beyond that range? Would JavaScript refer it as a new Infinity number? What are all the scenarios in JavaScript, where the value Infinity could be assigned to a variable in

问题 I've been running a huge Fortran code with Intel compiler version 13.1.3.192 under the debug mode (with -O0 -g -traceback -fpe3 flags being turned on). It gave me the following output message: ... ... forrtl: warning (402): fort: (1): In call to MPI_ALLGATHER, an array temporary was created for argument #1 forrtl: error (65): floating invalid Image PC Routine Line Source arts 00000000016521D9 pentadiagonal_ser 385 pentadiagonal.f90 arts 0000000001644862 pentadiagonal_ 62 pentadiagonal.f90

问题 I have been experimenting with the bubble sort code as I have recently started to gain my knowledge of C code. However I am unable to input NAN into the code for it to print out when building and running it. I am having the same problem with INFINITY AND -INFINITY. The code, however, works when I run the code and input NAN, INFINITY AND -INFINITY as one of the integers. Help would be appreciated, thanks. /* Bubble sort code */ #include <stdio.h> #include <math.h> int main() { float array[100]

问题 The .NET Json serializer serializes Double.PositiveInfinity and the like to things like Infinity, which aren't valid JSON. I'm now trying to use Json.NET to serialize an object to JSON, but I'd like to wrap it so that values like Infinity get converted to NULL, or the string "Infinity". How do I go about doing this? 回答1: The only way to do this is to serialize Double values as a custom type which provide information on top of the value. For example { 'isInfinity': 'true', 'isNan': 'false'