nested-loops

问题 I found several topics about pyparsing. They are dealing with almost the same problem in parsing nested loop, but even with that, i can't find a solution to my errors. I have the following format : key value; header_name "optional_metadata" { key value; sub_header_name { key value; }; }; key value; Key is alphanum Value may be type of Int, String, with alphanum + "@._" key/value may be after a brace block key/value may be in the file before the first brace block key/value before or after a

问题 I had two loops (one nested in the other one) and I was wondering if there is any difference in how I nest these loops. Results of Code 1 and Code 2 are the same (100,000x4 = 4x100,000 = 400,000) but jsPerf shows that Code 2 is roughly 50% faster than Code 1. I'd like to kindly ask for your advice, I don't understand the difference between the two. Thank you very much. var tt = function () { // do some stuff // for example: return (3); }; Test code 1: for (var i = 0; i < 100000; i++) { for

问题 I had two loops (one nested in the other one) and I was wondering if there is any difference in how I nest these loops. Results of Code 1 and Code 2 are the same (100,000x4 = 4x100,000 = 400,000) but jsPerf shows that Code 2 is roughly 50% faster than Code 1. I'd like to kindly ask for your advice, I don't understand the difference between the two. Thank you very much. var tt = function () { // do some stuff // for example: return (3); }; Test code 1: for (var i = 0; i < 100000; i++) { for

问题 I am a beginner in Python and want to solve the following problem: Given a list of n integer numbers and an integer result the correct operators (+, -, *, /) shall be found that solve a corresponding simple math equation. Example: For numbers = [2, 3, 4, 1] and result=13 the following solution should be found: 2 + 3 * 4 - 1 = 13. I wrote the following code which finds a solution for n =4 by doing a brute force approach with 3 nested for loops in which the operators are alternated. I struggle

问题 I am a beginner in Python and want to solve the following problem: Given a list of n integer numbers and an integer result the correct operators (+, -, *, /) shall be found that solve a corresponding simple math equation. Example: For numbers = [2, 3, 4, 1] and result=13 the following solution should be found: 2 + 3 * 4 - 1 = 13. I wrote the following code which finds a solution for n =4 by doing a brute force approach with 3 nested for loops in which the operators are alternated. I struggle

问题 I'm trying to create an array based on values from another data frame in Python. I want it to fill the array as such. If x > or = 3 in the dataframe then it inputs a 0 in the array. If x < 3 in the dataframe then it inputs a 1 in the array. If x = 0 in the dataframe then it inputs a 0 in the array. Below is the code I have so far but the result is coming out as just [0] array = np.array([]) for x in df["disc"]: for y in array: if x >= 3: y=0 elif x < 3: y=1 else: y=0 Any help would be much

问题 I would like to check all Elements of an vector against each other. By checking a condition an element should be removed. One approach was to erase the elements by nested for loops for (int a = 0; a < rs.size(); a++) { Point A = rs[a]; for (int b = 1; b <= rs.size(); b++) { Point B = rs2[b]; float distance = sqrt(pow(B.x - A.x, 2) + pow(B.y - A.y, 2) * 1.0); if (distance < 10.0) { if (distance > 0) { rs.erase(rs.begin() + b); } } } } but this would effect the vector and his size in runtime. A

问题 I would like to check all Elements of an vector against each other. By checking a condition an element should be removed. One approach was to erase the elements by nested for loops for (int a = 0; a < rs.size(); a++) { Point A = rs[a]; for (int b = 1; b <= rs.size(); b++) { Point B = rs2[b]; float distance = sqrt(pow(B.x - A.x, 2) + pow(B.y - A.y, 2) * 1.0); if (distance < 10.0) { if (distance > 0) { rs.erase(rs.begin() + b); } } } } but this would effect the vector and his size in runtime. A

问题 I'm playing with the bookstore XML from w3schools: <bookstore> <book category="cooking"> <title lang="en">Everyday Italian</title> <author>Giada De Laurentiis</author> <year>2005</year> <price>30.00</price> </book> <book category="children"> <title lang="en">Harry Potter</title> <author>J K. Rowling</author> <year>2005</year> <price>29.99</price> </book> <book category="web"> <title lang="en">XQuery Kick Start</title> <author>James McGovern</author> <author>Per Bothner</author> <author>Kurt

问题 This code I'm using is from this previously asked question. This question has been asked and answered plenty of times but I'm specifically asking for the order to be listed by size from largest to smallest. public static void main(String[] args) { String inputedWord = "ABIGWORD"; for (String str : breakStringIntoPieces(inputedWord, 2)) { System.out.print("\n") + str; } } //Pass in word and minimum //substring length to print public static List<String> breakStringIntoAllPossibleSubstrings