treemap

Key in TreeMap returning null

由 北城余情 提交于 2019-12-10 13:05:56
问题 So I have a very odd bug. I stumbled across it when I was originally using a keySet() to iterate over the first 10 keys of a large TreeMap. One of the keys was returning null, which should not be possible as far as my understanding goes. So I wrote the test code below: int i = 0; for (Map.Entry<String, Integer> es : sortedMap.entrySet()){ if (i >= 10) { break; } if (sortedMap.containsKey(es.getKey())){ System.out.println(es.getKey() + ":" + sortedMap.get(es.getKey())); } else { System.out

Java TreeMap custom comparator weird behaviour

由 ⅰ亾dé卋堺 提交于 2019-12-10 12:56:21
问题 I am trying to create a Map with sorted keys, sorted according to alphabetically first, and numerical last. For this I am using a TreeMap with a custom Comparator : public static Comparator<String> ALPHA_THEN_NUMERIC_COMPARATOR = new Comparator<String> () { @Override public int compare(String first, String second) { if (firstLetterIsDigit(first)) { return 1; } else if (firstLetterIsDigit(second)) { return -1; } return first.compareTo(second); } }; private static boolean firstLetterIsDigit

Unable to sort the list by ascending order

由 岁酱吖の 提交于 2019-12-10 10:21:06
问题 Map<String, String> map ; List<Map<String, String>> list = new ArrayList<Map<String, String>>(); /////OnCreate............. function1(){ map = new TreeMap<String, String>(); map.put("id", "id"); map.put("amont", "amount"); list.add(map); System.out.println(list); } input values for id=1,3,5,57,80 input values for amount=100,500,200,10,10000 Unable to sort the list by ascending order of amount. It still shows in the order it was inserted. How do I fix this? I appreciate any help. Thanks in

get the three highest values in a TreeMap

由 岁酱吖の 提交于 2019-12-10 07:50:01
问题 I am trying to find the three highest values in a TreeMap. I wrote a code that is kind of doing it, but I would like to ask whether you can suggest a more efficient way. Basically, I am saving each word of my text in a TreeMap along with the number of times it appears in the text. Then I am using a comparator to sort the values. Then I am iterating through the newly created Map until I reach the last three values, which are the highest values after the sorting and print them out. I am going

HanLP二元核心词典详细解析

由 瘦欲@ 提交于 2019-12-10 01:31:51
本文分析：HanLP版本1.5.3中二元核心词典的存储与查找。当词典文件没有被缓存时，会从文本文件CoreNatureDictionary.ngram.txt中解析出来存储到TreeMap中，然后构造start和pair数组，并基于这两个数组实现词共现频率的二分查找。当已经有缓存bin文件时，那直接读取构建start和pair数组，速度超快。 源码实现 二元核心词典的加载 二元核心词典在文件：CoreNatureDictionary.ngram.txt，约有46.3 MB。程序启动时先尝试加载CoreNatureDictionary.ngram.txt.table.bin 缓存文件，大约22.9 MB。这个缓存文件是序列化保存起来的。 ObjectInputStream in = new ObjectInputStream(IOUtil.newInputStream(path)); start = (int[]) in.readObject(); pair = (int[]) in.readObject(); 当缓存文件不存在时，抛出异常：警告: 尝试载入缓存文件E:/idea/hanlp/HanLP/data/dictionary/CoreNatureDictionary.ngram.txt.table.bin发生异常[java.io.FileNotFoundException:

10-利用思维导图梳理JavaSE-Java 集合

由 ℡╲_俬逩灬. 提交于 2019-12-09 16:26:04
10-利用思维导图梳理JavaSE-Java 集合 主要内容 1.Collection接口 2.Set接口 2.1.Set接口概述 2.2.HashSet类 2.3.TreeSet类 2.4.SortedSet接口 3.List接口 3.1.List接口概述 3.2.ArrayList类 3.3.LinkedList类 3.4.Vector类 4.Queue接口 5.Stack类 6.集合输出 6.1.集合遍历概述 6.2.Iterator接口 6.3.ListIterator接口 7.Map接口 7.1.Map概述 7.2.Map.Entry 7.3.HashMap 7.4.TreeMap 7.5.IdentityHashMap 8.属性类Properties 9.集合工具类Collections QQ/知识星球/个人WeChat/公众号二维码 本文为原创文章，如果对你有一点点的帮助，别忘了点赞、打赏、收藏、评论、转发哦！比心！如需转载，请注明出处，谢谢！ 来源： oschina 链接： https://my.oschina.net/u/2931098/blog/2206207

Clip SVG text to width of rectangle in a D3 treemap

由 雨燕双飞 提交于 2019-12-09 16:21:54
问题 I'm wondering if there is a simpler way to restrict the width of a text label than using a clip path. Here's an example of what I'm looking for with regard to labeling: treemap: Notice that the labels get truncated by the boundaries of the containing tiles. That particular example is implemented using <div> tags, which have this behaviour by default. But I'm using SVG <rect> and I'm hoping there is a more straight-forward way of doing this than a separate clip path defining another rect shape

Scala 2.8 TreeMap and custom Ordering

由 瘦欲@ 提交于 2019-12-09 06:42:07
问题 I'm switching from scala 2.7 and ordered to scala 2.8 and using ordering. It looks quite straight forward but I was wondering could I make it a little less verbose. For example: scala> case class A(i: Int) defined class A scala> object A extends Ordering[A] { def compare(o1: A, o2: A) = o1.i - o2.i} defined module A If I then try to create a TreeMap I get an error scala> new collection.immutable.TreeMap[A, String]() <console>:10: error: could not find implicit value for parameter ordering:

Time complexity of TreeMap operations- subMap, headMap, tailMap

由 China☆狼群 提交于 2019-12-08 23:43:30
问题 Does anyone know the time complexity of the operations of TreeMap like - subMap, headMap. tailMap. The time complexity of operations like get, put is O(logn). But the javadoc doesnt say much about the complexity for the above operations. The worst case complexity I can thinks of O(n) since it will go through the entire list if the set includes the last element. Can we confirm it? 回答1: For those questions having the source code on hand is very useful as with sufficient IDE support you can

Equivalent of C++ map.lower_bound in Java

由 江枫思渺然 提交于 2019-12-08 17:43:27
问题 My question is very basic, but I couldn't find the solution myself. I am used to writing algorithms in C++. There I very often use the std::map structure, together with all the auxiliary methods it provides. This method returns iterator to the first element of the map with key >= to the key given as parameter. Example: map<int, string> m; // m = { 4 => "foo", 6 => "bar", 10 => "abracadabra" } m.lower_bound(2); // returns iterator pointing to <4, "foo"> m.lower_bound(4); // returns iterator
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