numbers | 易学教程

Sort JavaScript String Array containing numbers

阅读更多关于 Sort JavaScript String Array containing numbers

问题 I have an array in JavaScript that contains the following: ["Value 1", "Value 5". "Value 10", "Value 11"]; How would I go about sorting this array so that it does not appear as follows: ["Value 1", "Value 10". "Value 11", "Value 5"]; But as: ["Value 1", "Value 5". "Value 10", "Value 11"]; Any help would be great. 回答1: If you are enthusiastic about writing it yourself, you can just parse the items with an regular expression and compare the second part. Those will match something like "Value\s

json_decode AND json_encode long integers without loosing data

阅读更多关于 json_decode AND json_encode long integers without loosing data

问题 As noted in the PHP documentation, when json_decode ing a data structure containing long integers, they'll be converted to floats. The workaround is to use JSON_BIGINT_AS_STRING , which preserves them as strings instead. When json_encode ing such values, JSON_NUMERIC_CHECK will encode those numbers back into large integers: $json = '{"foo":283675428357628352}'; $obj = json_decode($json, false, JSON_BIGINT_AS_STRING); $json2 = json_encode($obj, JSON_NUMERIC_CHECK); var_dump($json === $json2);

generate random numbers of which the sum is constant

阅读更多关于 generate random numbers of which the sum is constant

问题 I am thinking if there is anyway to generate a set of random numbers of which the sum is always a constant. For example, 20 can be divided into 5 numbers ( 1, 2,3,4,10) I don't care what each of the 5 numbers is as long as their sum is equal to 20. Is there anyway to do so programmatically? 回答1: To get a uniform distribution, the trick is to think of your sum as a number line, and rather than generating random numbers for the segments, generate n-1 numbers as points along the line, and

10个让朋友对你刮目相看的CoffeeScript单行代码绝技

阅读更多关于 10个让朋友对你刮目相看的CoffeeScript单行代码绝技

【推荐】2019 Java 开发者跳槽指南.pdf(吐血整理) >>> 或许你已经看过了 Marcus Kazmierczak 的这篇在HN上颇受欢迎的“ 10个让朋友对你刮目相看的Scala单行代码绝技 ”了，尽管我对Scala并不了解（Java也是），但是这看起来还真不错，于是我也有点手痒，想让我的朋友们也对我刮目相看一小下——不过不是从Java到Scala，我是从Javascript到CoffeeScript，下面的例子都是基于 node.js 环境的。 1. 列表中的每项乘2 Marcus的第一个例子演示了map函数，我们可以使用range语法以及一个匿名函数来完成同样的事情： [1..10].map (i) -> i*2 我们还有下面这个更易读的版本： i * 2 for i in [1..10] 2. 数列求和 Javascript（以及CoffeeScript扩展）同样有原生的 map 以及 reduce 函数： [1..1000].reduce (t, s) -> t + s (reduce == reduceLeft, 还有reduceRight) 3. 检查字符串是否包含某个单词这实在是再简单不过了，因为我们有some方法，只要数组中的任何元素满足条件它就会返回true： wordList = ["coffeescript", "eko", "play

VB.net Need Text Box to Only Accept Numbers

阅读更多关于 VB.net Need Text Box to Only Accept Numbers

问题 I'm fairly new to VB.net (self taught) and was just wondering if someone out there could help me out with some code. I'm not trying to do anything too involved, just have a TextBox that accepts a numeric value from 1 to 10. I don't want it to accept a string or any number above 10. If someone types a word or character an error message will appear, telling him to enter a valid number. This is what I have; obviously it's not great as I am having problems. Thanks again to anyone who can help. If

Input validation of an Integer using atoi()

阅读更多关于 Input validation of an Integer using atoi()

问题 #include "stdafx.h" #include <stdlib.h> void main() { char buffer[20]; int num; printf("Please enter a number\n"); fgets(buffer, 20, stdin); num = atoi(buffer); if(num == '\0') { printf("Error Message!"); } else { printf("\n\nThe number entered is %d", num); } getchar(); } The above code accepts a number in the form of a string and converts it to integer using atoi. If the user inputs a decimal number, only the bit before the decimal is accepted. Moreover, if the user enters a letter, it

How to generate random positive and negative numbers in Java [duplicate]

阅读更多关于 How to generate random positive and negative numbers in Java [duplicate]

问题 This question already has answers here : How do I generate random integers within a specific range in Java? (66 answers) Closed 12 months ago . I am trying to generate random integers over the range (-32768, 32767) of the primitive data type short. The java Random object only generates positive numbers. How would I go about randomly creating numbers on that interval? Thanks. 回答1: You random on (0, 32767+32768) then subtract by 32768 回答2: Random random=new Random(); int randomNumber=(random

Python - Find the greatest number in a list of numbers

阅读更多关于 Python - Find the greatest number in a list of numbers

问题 Is there any easy way or function to determine the greatest number in a python list? I could just code it, as I only have three numbers, however it would make the code a lot less redundant if I could tell the greatest with a built in function or something. 回答1: What about max() highest = max(1, 2, 3) # or max([1, 2, 3]) for lists 回答2: You can use the inbuilt function max() with multiple arguments: print max(1, 2, 3) or a list: list = [1, 2, 3] print max(list) or in fact anything iterable. 回答3

Android Number Picker Dialog [closed]

阅读更多关于 Android Number Picker Dialog [closed]

问题 Closed. This question is off-topic. It is not currently accepting answers. Want to improve this question? Update the question so it's on-topic for Stack Overflow. Closed 5 years ago . Does anyone have any dialogs that will allow a user to pick a number within a certain range? It seems like this would be a fairly common need, but I can't find a common dialog for it and I'd rather not have to spend the time creating my own. Any help? 回答1: I know that more than two years passed but answer is

How to limit the maximum value of a numeric field in a Django model?

阅读更多关于 How to limit the maximum value of a numeric field in a Django model?

问题 Django has various numeric fields available for use in models, e.g. DecimalField and PositiveIntegerField. Although the former can be restricted to the number of decimal places stored and the overall number of characters stored, is there any way to restrict it to storing only numbers within a certain range, e.g. 0.0-5.0 ? Failing that, is there any way to restrict a PositiveIntegerField to only store, for instance, numbers up to 50? Update: now that Bug 6845 has been closed, this