traversal

Scala: how to traverse stream/iterator collecting results into several different collections

由 为君一笑 提交于 2019-12-06 11:00:58
问题 I'm going through log file that is too big to fit into memory and collecting 2 type of expressions, what is better functional alternative to my iterative snippet below? def streamData(file: File, errorPat: Regex, loginPat: Regex): List[(String, String)]={ val lines : Iterator[String] = io.Source.fromFile(file).getLines() val logins: mutable.Map[String, String] = new mutable.HashMap[String, String]() val errors: mutable.ListBuffer[(String, String)] = mutable.ListBuffer.empty for (line <- lines

What is the most efficient way to retrieve the column index for rows affected by “rowspan”?

由 可紊 提交于 2019-12-06 07:29:16
问题 Consider the following table: <table> <thead> <tr> <th scope="col" /> <th scope="col">A</th> <th scope="col">B</th> <th scope="col">C</th> </tr> </thead> <tbody> <tr> <th scope="row">1</th> <td>Apples</td> <td>Oranges</td> <td>Pears</td> </tr> <tr> <th scope="row">2</th> <td rowspan="2">Subcategory Heading</td> <td>ASP.Net</td> <td>Other</td> </tr> <tr> <th scope="row">3</th> <td>MVC</td> <td>PHP</td> </tr> <tr> <th scope="row">4</th> <td>Red</td> <td>Green</td> <td>Blue</td> </tr> </tbody>

Is os.walk() missing symlinks to directories?

由 点点圈 提交于 2019-12-06 05:44:32
I have a directory containing some files, some directories, some symlinks to files and some symlinks to directories. When I do os.walk() with followlinks=false in the directory, I get the files and symlinks to files in the filenames list and the directories in the dirnames list. But the symlinks to directories does not show up anywhere. Is this a bug or a feature in Python, or am I doing something wrong? I expect the symlinks to directories to show up in the filenames list, because they are not directories but symlinks, and the other symlinks (to other files) show up in the filenames list.

How to generate URL to view when using Traversal?

由 喜欢而已 提交于 2019-12-06 05:16:23
问题 When URL Dispatch is used, we can easily generate a URL to a view because every view has a distinct route_name like: login.py: @view_config(route_name='login') index.pt: <a href="${request.route_url('login')}">Login</a> But how to do this in traversal? Since there is no instance of resources 'Login' available, I don't know how to generate URL to view login. 回答1: In traversal you are required to know the structure of your tree, and you must be able to load context objects on demand. The URLs

c++: pass function as parameter to another function

由 痴心易碎 提交于 2019-12-06 04:34:07
问题 i am currently implementing a binary tree in c++ and i want to traverse it with a function called in_order(). is there any way to pass a function as an argument, so that i can do things like below (without having to write the code to traverse the list more than once)? struct tree_node; // and so on class tree; // and so on void print_node () { // some stuff here } // some other functions tree mytree(); // insert some nodes mytree.in_order(print_node); mytree.in_order(push_node_to_stack);

Applying a Logarithm to Navigate a Tree

由 我与影子孤独终老i 提交于 2019-12-06 02:44:48
问题 I had once known of a way to use logarithms to move from one leaf of a tree to the next "in-order" leaf of a tree. I think it involved taking a position value (rank?) of the "current" leaf and using it as a seed for a fresh traversal from the root down to the new target leaf - all the way using a log function test to determine whether to follow the right or left node down to the leaf. I no longer recall how to exercise that technique. Can anyone re-introduce me? I also don't recall if the

Modeling an ordered tree with neo4j

由 南笙酒味 提交于 2019-12-06 01:38:48
问题 I'm just getting started with neo4j, and I understand the principles of the graph and relationships, but I'm having a little bit of trouble with certain structures I want to model. I wanted to use it on a programming language project, and store the AST of a parsed source file. From there, I plan on adding a lot of additional data and relationships to the nodes to help with analysis and tooling, but the fundamental AST is still a little difficult. The naive way of making a tree would be to

Is there more to optimizing CSS than minimizing character count?

由 穿精又带淫゛_ 提交于 2019-12-05 21:15:44
I've been reading a lot about jQuery optimization and how you can alter your selectors to cut down on the amount of DOM traversal, but I haven't heard much about CSS optimization outside of the usual minifying process. Is there any way to optimize your CSS loading/processing outside of just reducing character count and server requests? You can definitely optimise your selectors for performance. One key point is that CSS parsers read selectors right to left, whereas javascript selector engines (like jQuery etc) read them left to right. Basically though, the general principles are the same - you

Depth First Search on 2-D array

由 杀马特。学长 韩版系。学妹 提交于 2019-12-05 19:05:23
I am trying to learn DFS by creating a program that navigates my ogre through a maze (2d array).This is similar to a dailyprogramming challenge, but I am doing it with just a 1x1 ogre. My maze: static int[][] maze = { {2,1,0,0,0,0,0,0,0,0}, {0,0,1,0,0,0,0,0,0,0}, {1,0,0,0,0,1,0,1,0,0}, {0,0,0,0,0,0,0,0,0,0}, {0,0,1,1,0,0,0,0,0,0}, {0,0,1,0,0,0,0,1,0,1}, {1,1,0,0,0,0,0,0,0,0}, {0,0,0,0,0,0,0,0,0,0}, {0,0,0,0,0,1,1,0,0,0}, {0,0,0,0,0,1,0,0,0,3}}; Where 2 is my hero (0,0), 3 is my goal (9,9), 1s are obstacles, and 0s are traverseable space. Since I am new to this, I doubt it will be needed, but

HTTP TCP connection to web server behind NAT

由 ≯℡__Kan透↙ 提交于 2019-12-05 18:35:29
My question is the same as this one but hopefully adds clarity to get an answer. After reading this fantastic article on the specifics behind NAT Traversal along with a general summary of methods found here , I'm wondering if the scenario has been accomplished or is possible. I'm writing software that serves web pages on any specified port, and am wondering if it is possible to have a web client from the WAN side connect to this server that is behind a NAT router. The reason this I'm finding this difficult is because: I don't want to tell the user (who owns the web server) to configure their
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