arrays

问题 Python 2.7, numpy, create levels in the form of a list of factors. I have a data file which list independent variables, the last column indicates the class. For example: 2.34,4.23,0.001, ... ,56.44,2.0,"cloudy with a chance of rain" Using numpy, I read all the numeric columns into a matrix, and the last column into an array which I call "classes". In fact, I don't know the class names in advance, so I do not want to use a dictionary. I also do not want to use Pandas. Here is an example of the

问题 For instance, this is 5 choose 2: var array = [0,1,2,3,4]; var result = array.flatMap( (v, i) => array.slice(i+1).map(w => [v, w]) ); console.log(result); How would I be able to do 5 choose 3 using this method? 回答1: Just add another level of nesting: var array = [0,1,2,3,4]; var result = array.flatMap((v, i) => array.slice(i+1).flatMap((w, j) => array.slice(i+1+j+1).map(u => [v, w, u] ) ) ); console.log(result); At this point, it might be easier to do with recursion though: function choose

问题 I need to filter array of object by another array of object without knowledge of exact properties in criterias array. Let's take a look to example for better understanding. Here is an array that I need to filter const dataset = [ { id: "4", someval1: "10", someval2: "20", someval3: "30", someval4: "40" }, { id: "10", someval1: "10", someval2: "20", someval3: "30", someval4: "40" }, { id: "22", someval1: "102", someval2: "202", someval3: "302", someval4: "40" }]; Here is an array which has

问题 I need to filter array of object by another array of object without knowledge of exact properties in criterias array. Let's take a look to example for better understanding. Here is an array that I need to filter const dataset = [ { id: "4", someval1: "10", someval2: "20", someval3: "30", someval4: "40" }, { id: "10", someval1: "10", someval2: "20", someval3: "30", someval4: "40" }, { id: "22", someval1: "102", someval2: "202", someval3: "302", someval4: "40" }]; Here is an array which has

问题 I am trying to create a 2d array of String using Streams: String[] fruit1DArray; String[][] fruit2DArray; Map<String, String> fruitMap = new HashMap<>(); fruitMap.put("apple", "red"); fruitMap.put("pear", "green"); fruitMap.put("orange", "orange"); fruit1DArray = fruitMap.entrySet() .stream() .map(key -> key.getKey()) .toArray(size -> new String[size]); fruit2DArray = fruitMap.entrySet() .stream() .map(entry-> new String[]{entry.getKey()}) .toArray(size -> new String[size][1]); System.out

问题 I am trying to create a 2d array of String using Streams: String[] fruit1DArray; String[][] fruit2DArray; Map<String, String> fruitMap = new HashMap<>(); fruitMap.put("apple", "red"); fruitMap.put("pear", "green"); fruitMap.put("orange", "orange"); fruit1DArray = fruitMap.entrySet() .stream() .map(key -> key.getKey()) .toArray(size -> new String[size]); fruit2DArray = fruitMap.entrySet() .stream() .map(entry-> new String[]{entry.getKey()}) .toArray(size -> new String[size][1]); System.out

问题 I'm trying to split text the following like on spaces: var line = "Text (what is)|what's a story|fable called|named|about {Search}|{Title}" but I want it to ignore the spaces within parentheses. This should produce an array with: var words = ["Text", "(what is)|what's", "a", "story|fable" "called|named|about", "{Search}|{Title}"]; I know this should involve some sort of regex with line.match(). Bonus points if the regex removes the parentheses. I know that word.replace() would get rid of them

问题 I'm trying to split text the following like on spaces: var line = "Text (what is)|what's a story|fable called|named|about {Search}|{Title}" but I want it to ignore the spaces within parentheses. This should produce an array with: var words = ["Text", "(what is)|what's", "a", "story|fable" "called|named|about", "{Search}|{Title}"]; I know this should involve some sort of regex with line.match(). Bonus points if the regex removes the parentheses. I know that word.replace() would get rid of them

问题 I am doing some tests with Ruby 2.7.1 on FreeBSD 12.1. I know how to extend a class with module with for instance this : class Myclass def mymethod extend Mymodule end end But is it possible to obtain the same result with something that looks like this : class Myclass def mymethod var = "Mymodule" extend var end end If I do this like that, I off-course obtain an error, since extend is pointing to a string and not a module. Here are some explanations - it would be useful in the following

问题 I am struggling with an array formula, that logically seems sound, however it doesn't appear to be working correctly. I have been working on a complex sheet, that is not to include VBA, which has made it formula heavy, and using arrays instead. In the image below, the first part is the problem, for the data shown in columns A-F, I wish to get a sum of the values that match the values in I1:K1. The formula I have used to begin with can be seen in the first image also, this evaluates, pressing