- 可可
-
1, 4000x30%=1200 votes (票)
2,20%未决定的人,即有:4000x20%=800 votes
3,这800人中,按3:5分配,即:8分之3投给A,8分之5投给B
4, 所以投给A的就是:800x3/8=300 votes
3,所以A得最后得票是:1200+300=1500 votes
答案是:B
Had Paul received six more votes in the last election,he would have been our chairman now.
would have been 改为 would be2023-07-23 05:46:334
C语言选举代表问题
错误的地方比较多。首先,字符串的存储一个汉字要占两个字节的位置,所以两个汉字就要用了4个字节,另外再加上一个字符串的结束服务,表示两个字的姓名,就需要至少需要五个字符。另外,比较致富串是否相等,应该要使用头文件string.h。下面比较字符串是否相等,要使用其中的字符串比较函数strcmp。具体的程序已经修改完成,并且运行测试通过。#include#include main(){ int i,k; char j[5]; //两个汉字至少要5,三个汉字至少要7 struct person { int votes; char j[5]; } zhang= {0,"张三"},zhao= {0,"赵六"},wang= {0,"王二"},li= {0,"李四"},liu= {0,"刘五"}; for(i=1;; i++) { printf("请输入支持人的姓名,结束请输入## "); scanf("%s",j); if(strcmp(j,zhang.j)==0) zhang.votes++; if(strcmp(j,wang.j)==0) wang.votes++; if(strcmp(j,zhao.j)==0) zhao.votes++; if(strcmp(j,liu.j)==0) liu.votes++; if(strcmp(j,li.j)==0) li.votes++; if(strcmp(j,"##")==0) { break; } } printf("1 %s %d ",zhang.j,zhang.votes); printf("2 %s %d ",wang.j,wang.votes); printf("3 %s %d ",zhao.j,zhao.votes); printf("4 %s %d ",liu.j,liu.votes); printf("5 %s %d ",li.j,li.votes);}2023-07-23 05:46:481
用java做一个简单的投票系统,有三名表演者,代号,1.2.3。观众依次投票,已数字0结束,然后还
import java.io.BufferedReader;import java.io.InputStreamReader;public class Vote {public static void main(String args[]) {try {String[] persons = new String[]{"1","2","3"};Integer[] votes = new Integer[]{0,0,0};BufferedReader sin = new BufferedReader(new InputStreamReader(System.in));String readline;System.out.println("================投票开始===============");System.out.println("请按1,2,3投票,Enter确认");System.out.println("按0-->Enter结束投票,公布结果 ");readline = sin.readLine(); // 从系统标准输入读入一字符串while (!readline.equals("0")) {String voteStr = readline;if(persons[0].equals(voteStr)){votes[0] +=1;}else if(persons[1].equals(voteStr)){votes[1] +=1;}else if(persons[2].equals(voteStr)){votes[2] +=1;}else{System.out.println("无效的投票!");}readline = sin.readLine(); // 从系统标准输入读入一字符串} // 继续循环System.out.println("================投票结束===============");System.out.println("================结果公布===============");System.out.println(persons[0]+"================"+persons[1]+"==============="+persons[2]);System.out.println(votes[0]+"================"+votes[1]+"==============="+votes[2]);} catch (Exception e) {System.out.println("Error" + e); // 出错,则打印出错信息}}}2023-07-23 05:47:121
这个c语言程序怎么改???if(strcmp(na,can[i].name)==0)这个是错的吗???
strcmp是c的库函数,功能是把()中的形参指针指向的字符串比较一下,按对应字符的ascii码大小确定返回值:前者大于后者时返回1,相等时返回0,前者小于后者时返回-1。strcmp(name,eng[i].name)的意思就是比较name和eng[i].name指向的字符串谁大谁小或相等。2023-07-23 05:47:312
英语翻译: 我们将要选取10个幸运观众,然后从他们当中发起投票,获得最多选票的两个人将获胜
We will pick out ten lucky audiences and then initiate a vote among them, the two lucky audiences with highest votes would be the winners.2023-07-23 05:47:395
java servlet写投票系统,用数据库统计票数问题
对,1L说了。2023-07-23 05:47:532
豆瓣和imdb的评分哪个专业点
简单的说imdb更具有客观性,豆瓣更适合国人的口味,时光网评分普遍偏高不具有参考价值。我觉得这么问,目的在于这个评分是否对于我们有参考价值,是否能影响我们买票走进电影院,所以我觉得需要从几个方面来看待这个问题。首先,votes。imdb分数并不能完全反映电影的水平,同时需要考虑vote数,比如>1000 votes或者>2000 votes。有些片分高,但是votes数很少,这样就没有参考价值,一般超过1w的votes就能正确反映片子的水平了。这个到豆瓣上同样适用,基数越大,分数越具有参考价值。另外亚洲的片子在imdb上普遍votes太少,基本上不具有参考价值,亚洲的电影还是参考国内的评分比较好。其次,地域文化差异的问题。众所周知,由于天朝的GFW,国内用户是没办法直接访问imdb的,需要翻墙或者把域名改成ip地址。因此imdb的评分大部分只代表了欧美用户的口味,并不一定适合于国人的口味。有很多片子在国外评价很差票房很烂,国内引进却能获得不错的票房和口碑。上段说到亚洲电影普通votes太少,也是欧美大众很少有机会接触到亚洲的电影,华语电影就更难了,很多日韩港片几乎没有imdb链接,因此这些imdb的评分完全不具有参考价值。再次,评分机制。imdb的评分是可以选1--10分的,而豆瓣只能选1到5星,这种差异也会造成不同分数的差异,比如我在imdb上很少给片子10分的,因为我认为很少有一部电影能够达到10分,往往很不错的我就给9分了,而在豆瓣上5星表示力荐,9分的电影我觉得已经足够力荐所以我当然会给5星。这也是分数有差别的一个原因。普遍来说,一部公认的好片在豆瓣上分还是会高一点的。次次,在imdb上,会有刷分的问题。就是说top50,top10的电影是相对固定的,每年顶多1到2部电影能进入到top50里面,而top10的电影也是有一批固定的粉丝的,他们对于自己喜欢的电影是无法忍受被其他新进来的电影刷下去的。比如当初TDK被粉丝们刷到TOP1的时候,肖申克救赎的影迷和教父的影迷就无法忍受了,于是刷分就开始,把后两部评分往上刷把TDK往下刷,最终TDK的评分在8.9,No.8。所以一般一部电影上映之后1年分数和排名才会较为稳定。最后,说到底电影的评价完全在个人。一百个人眼中有一百个哈姆雷特,这和你自己的口味以及人生阅历是有关系的,分数只是一个简单的参考,只是影响你买票走进电影院的一个因素而已。很多动作片分不高6分,但是也可以一看;有些文艺片7分,也不一定看的很舒服;有些片快8分了你也不一定能看懂。也有很多人看片只要是大片就看,也有人只要有自己喜欢的明星就行,也有人只喜欢看某种类型的片。当然,如果你只是一位为了没事放松自己进电影院看一部电影的话,我觉得你可以综合imdb和豆瓣的评分来决定是否要买票进入电影院。2023-07-23 05:48:191
篮球运动员英文
basketballplayer2023-07-23 05:48:304
英语强人帮我翻译下这段文字了.先谢谢了
有一个不同的问题有关的现任署长提名谁不能赢得选举。根据所谓的缓缴规则,失去现任署长提名继续担任董事职位,直至取代,除非这类现任董事辞职。因此,实施多数表决将影响甚微,没有变更为缓缴规则。但是, 简单地消除缓缴规则将导致在该问题上面列出。 累积投票应有别于多元性和多数表决。而多元性和多数表决涉及到的门槛要求,为打赢主任选举,累积投票涉及到的选票数目1 股东可投在选举中。与累积投票,每一股进行很多票由于有空缺有待填补,和股东可能会分发选票,为所有该等股份之间的主任被提名人以任何方式想要的。 累积投票是普遍旨在促进少数股东的影响力,在这方面的大股东或股东集团是不放心,能够填补每名董事席位与自己的提名。某些倡议者大多数投票的标准认为应该有一个雕刻出-让多数投票-公司有累积投票。 累积投票制是不是一个新概念,在美国。累积投票长期以来一直使用的美国的公司,以此确保少数股东权益是听取和代表嘿嘿!电脑翻译的 不太准确2023-07-23 05:49:091
jqurey 遍历 div内的所有input单选复选按钮并判断是否选中?
js可这样判断是否选中$(".votesubject").find("input").each(function () {if ($(this).prop("checked", true)) {alert($(this).prop("value"))}}); 也可这样$("input[name=votetitle]").each(function () {//if (this.checked) {// alert($(this).val());//} var radios = $(this); for (i = 0; i < radios.length; i++) {if (radios[i].checked) { votenum = parseInt(radios[i].value)+1; votes += votenum + "@"; ids+=$(this).attr("id")+"@"ischeck = false;}}}); 我需要的功能js方法:$(window).ready(function () { $("#tj").click(function () { //$(".votesubject").find("input").each(function () { // if ($(this).prop("checked", true)) { // alert($(this).prop("value")) // } // }); var ids = ""; var votes = ""; var votenum; var ischeck = true; $("input[name=votetitle]").each(function () { //if (this.checked) { // alert($(this).val()); //} var radios = $(this); for (i = 0; i < radios.length; i++) { if (radios[i].checked) { votenum = parseInt(radios[i].value)+1; votes += votenum + "@"; ids+=$(this).attr("id")+"@" ischeck = false; } } }); if (ischeck) { alert("请勾选选项后再进行提交"); return false; } if (!ischeck) { if (ids.length > 1) { ids = ids.substring(0, ids.length - 1); } if (votes.length > 1) { votes = votes.substring(0, votes.length - 1); } $("#votenum").val(votes); $("#ids").val(ids); alert("感谢您的参与。"); $("#form1").submit(); } }); $("#ck").click(function () { window.location = "voteview?cid= " + $("#classid").val() + "&id=" + $("#vid").val() + " "; });});附上相关选中的写法 $("[name="checkbox"]").attr("checked",true);//全选 $("[name="checkbox"]").removeAttr("checked");//取消全选 $("#checkbox").attr("checked"); 返回的是checked或者是undefined解决办法 JQ1.6之后,可以通过attr方法去获得属性,通过prop方法去获得特性 $("#cb").attr("tagName"); //undefined $("#cb").prop("tagName"); //INPUT2023-07-23 05:49:171
寻IMDB评分的详细资料,他的权威性如何?
1楼已经很详细了~2023-07-23 05:49:241
错误 1 无法将类型“int?”隐式转换为“int”。存在一个显式转换(是否缺少强制转换?)
var votes = (from v in db.VoteItem where v.TitleID == (Int32)Parse(Request.QueryString["titleid"].ToString()) select v.ItemCount).Sum();2023-07-23 05:49:322
The outcome of the election was announce before all of the votes had been counted. 语法问题
The outcome of the election was announce before all of the votes had been counted.这里announce是名词, before all the votes是announce的介词短语做定语,修饰名词announce。announce before all of the votes had been counted.是一个完整的表语从句。2023-07-23 05:49:391
statutory voting system到底是什么样的投票方式?
What is "Statutory Voting"Statutory voting is a corporate voting procedure in which each shareholder is entitled to one vote per share and votes must be divided evenly among the candidates or issues being voted on. Statutory voting, sometimes known as straight voting, is one of two stockholder voting procedures and the more common option. In statutory voting, if you owned 50 shares and were voting on six board positions, you could cast 50 votes for each board member, for a total of 300 votes. You could not cast 20 votes for each of five board members and 200 for the sixth.2023-07-23 05:49:482
投票英语怎么说
"我已经投票了"英语怎么翻译 我已经投票了 I have already voted 投票给我 英语怎么说 1 Remember to vote for me 2 I remember to cast 5 votes/Please remember to vote for him 3 I need 5 tickets, can monitor the election 4 Do you know how many people voted for you? 5 Have you got how many tickets? 6 Y耽u cannot vote。 下面的以后的明天或后天 投票英语怎么说 vote 投票数用英语怎么说 Votes 投票用英语怎么说 投票这个词语属于一般现在时,应该是:voteding “投票”的英文怎么写? vote 投票赞成某人 / 投票 反对某人 英语 1 支持和反对 支持support; stand by 反对opposite 投票支持xx: vote for xx 投票反对xx: vote against xx 2 我属虎 I was born in the year of tiger. I was born in the tiger year in China. I was born in xx俯x, it was a tiger year in Chinese horoscope. horoscope 星相学 希望回答对你有帮助2023-07-23 05:50:331
IMDB评分是什么意思呀?
imdb就是环球电影数据库的英文首字母缩写www.imdb.com就是它的官方网站,如果英文还可以的话,可以自己去看看2023-07-23 05:50:524
Here is a message to every man and woman _____ A who voe B who votes 选那个,为啥?
应该选择B,因为前面的先行词被every所修饰,所以主语应该被看作是第三人称单数2023-07-23 05:51:111
《机动部队》系列电影的顺序?
除了第一部和同胞是连得可以看,其余的劝你别看很恶心,粗制滥造的山寨版2023-07-23 05:51:285
求一篇有关环境的英语新闻报道,其中有对话采访!
Britain Enters Final Day of Campaigning Before ElectionsBritain"s top party leaders are taking full advantage of their last day of campaigning before Britons go to the polls. Late Wednesday night, Labor leader Gordon Brown visited steel workers on an overnight shift. "I don"t need to tell you that this election is about the future," said Brown. "It"s about the future of our industry, the future of our jobs, the future of our young people." Mr. Brown is facing a tight election. The Conservative Party, led by David Cameron, has topped the latest opinion polls. And, the Liberal Democrats -- traditionally a marginalized party in what has largely been a two-party system -- are scoring high in opinion polls.Rodney Barker is a political academic and professor at the London School of Economics. "The three candidates have been up to making themselves as busy as possible," explained Barker. "David Cameron, the Conservative leader, so visible that he"s even worked through the night -- he hasn"t slept."Barker says this last day of campaigning is crucial, because so many Britons still have not made up their mind. A survey published by the research group ComRes Tuesday said 2.5 million people who say they are certain to vote say they are still undecided who to vote for and more than a third of voters said it was "quite possible" they would change their mind on who to vote for by the time the polls open Thursday morning. Rodney Barker says it is all up in the air."The one thing which one can say about this election -- and we haven"t been able to say this for any election within living memory -- is that the only certain thing is that we cannot predict the outcome, even on the day before the poll," added Barker.The ComRes poll shows the Conservatives winning 37 percent of votes, Labor on 29 percent and the Liberal Democrats on 26 percent.With the votes split this way, no single party would win a majority of seats in parliament. In that case, the shape of Britain"s future government will depend on coalitions. The balance is likely to be tipped by the Liberal Democrats, but so far their leader, Nick Clegg, has refused to say whether his party would side with the Conservatives or Labor. Barker says what this means is that it could be weeks before the composition of Britain"s future government becomes clear. "Even when we know the result of the election, we may not know what the result is in terms of government -- who will successfully make a deal with who to make what sort of government," noted Barker.If no single party is able to win a majority of parliament seats, current Prime Minister Gordon Brown would have the right to stay in office until a new government can be formed.2023-07-23 05:52:081
The suggestion he put forward was adopted with 16 votes _____ and 15 against it.
答案A 试题分析:短语辨析。A支持,赞成;B回应;C纪念…;D关于;句意:他在会议上提出的建议有16票支持,15票反对。故A正确。 考点:考查短语辨析。 点评:本题的短语都是与介词In连用的,要在上下文语境中加以辨析,在平时加强识记。 查看原帖>>2023-07-23 05:52:151
请问各位英语高手
We must accept finite disappointment, but we must never lose infinite hope.2023-07-23 05:52:341
简单多数/绝对多数 用英语怎么说?
the most2023-07-23 05:52:443
many candidates for parliament were afraid to support abolition______they should lose votes。
意为:国会议员都不敢支持废奴议案唯恐失去选票。lest为唯恐、以免、担心。选because意思就不对了。2023-07-23 05:52:522
求一部美国经典的电影,就是一个富商生日,他弟弟送他一个生日礼物,就是找人杀他.......
剧情不错 我也想看看那个说致命游戏 我看过的一个叫致命游戏的怎么不是这剧情啊 我看致命游戏是 角色在游戏中怎么牺牲的 现实中也那么牺牲2023-07-23 05:53:021
IMDb权威认证是什么
IMDB 基于网友的个性海量评分,其核心排名算法如下: The formula for calculating the Top Rated 250 Titles gives a true Bayesian estimate: weighted rating (WR) = (v ÷ (v+m)) × R + (m ÷ (v+m)) × C where: R = average for the movie (mean) = (Rating) v = number of votes for the movie = (votes) m = minimum votes required to be listed in the Top 250 (currently 3000) C = the mean vote across the whole report (currently 6.9) for the Top 250, only votes from regular voters are considered.http://movie.douban.com/doulist/1518184/如果有兴趣可收藏此豆列,录有最新的IMDB TOP2502023-07-23 05:53:371
如何查询一部电影在IMDB中的具体排名?
环球电影资料库里有,几乎所有的电影资料都能在上面找到.也有IMDB排名.参考资料:http://www.mov6.com/IMDB评分方法IMDB是目前全球互联网中最大的一个电影资料库,里面包括了几乎所有的电影,以及1982年以后的电视剧集。IMDB的资料中包括了影片的众多信息,演员,片长,内容介绍,分级,评论等,就个人买碟而言,很大程度上也是参考IMDB的得分。而IMDB的得分又是如何来的呢?它的可靠性又有多少呢?让我们通过《魔戒1:护戒使者》来做具体分析吧,先看上图:这张图就是魔戒1的所有评分者的分数的一个条状统计图。从中我们可以看到各个分数段的大致比例,比如这儿就可以发现,超过一半的人是打满分的。根据IMDB网站上公布的TOP250评分标准:imdb top 250用的是贝叶斯统计的算法得出的加权分(Weighted Rank-WR),公式如下:weighted rank (WR) = (v ÷ (v+m)) × R + (m ÷ (v+m)) × C其中:R = average for the movie (mean) = (Rating)(是用普通的方法计算出的平均分)v = number of votes for the movie = (votes)(投票人数,需要注意的是,只有经常投票者才会被计算在内,这个下面详细解释)m = minimum votes required to be listed in the top 250 (currently 1250)(进入imdb top 250需要的最小票数,只有三两个人投票的电影就算得满分也没用的)C = the mean vote across the whole report (currently 6.9)(目前所有电影的平均得分)另外重点来了,根据这个注释:note: for this top 250, only votes from regular voters are considered.只有‘regular voters‘的投票才会被计算在IMDB top 250之内,这就是IMDB防御因为某种电影的fans拉票而影响 top 250结果,把top 250尽量限制在资深影迷投票范围内的主要方法。regular voter的标准不详,估计至少是“投票电影超过xxx 部以上”这样的水平,搞不好还会加上投票的时间分布,为支持自己的心爱电影一天内给N百部电影投票估计也不行。因此,细心的人可以注意到,列入IMDB top 250的电影,其主页面上的分数与250列表中的分数是不同的。以魔戒1为例,它在自己的页面[url]http://www.imdb.com/title/tt0120737/[/url]中的分数是8.8,而列表中是8.7。一般 250表中的得分都会低于自己页面中的得分,越是娱乐片差距越大。这大概是因为regular voter对于电影的要求通常较高的关系。2023-07-23 05:53:451
不少好莱坞动画电影的豆瓣评分远高于imdb评分,是什么原因导致了这一情况?
水军多吧2023-07-23 05:53:533
求一篇JAMES在NBA获得MVP的英文介绍?
JAMES NBA regular season MVP awardThe NBA regular season individual awards season, the highest honor - the most valuable player (MVP) yesterday go in the "Little Emperor" James name. In this way, the Cavaliers headed into NBA players in the history of the tenth player award in consecutive seasons. Earlier in the award selection, a total of nine players for two consecutive seasons was crowned the regular season MVP. They are superstars Russell, Wilt Chamberlain, Kareem Abdul-Jabbar, Malone, Bird, "Magic" Johnson, Michael Jordan, Tim Duncan and Steve Nash, of which Russell, Chamberlain and Bird superior, had three consecutive seasons of "value the highest. " The same day, James"s University in his hometown of Akron received the blessing of more than 3000 fans. Career when he won the second MVP trophy, the right high school teammates, coaches and his mother, thanked his girlfriend, and finally he invited, including O"Neill, Williams and other Cavaliers teammates came to power, and his share the joy of winning. "My name can be carved on this trophy," James said, "but they paid a lot of teammates." In this season"s regular season, James field team contributions are 29.7 points, 7.3 rebounds, 8.6 assists. In the James led the Cavaliers in the record, following last season ranked full league standings after the first, with 61 wins this season ranks all 21 league negative to the first. James made the selection in a landslide victory, winning total of 123 media workers from the United States and Canada and 116 in the hands of global fans first-place votes, total points over 1205 points. The poll is the second integral thunder team Durant (4 first-place votes), while the Lakers Kobe Bryant points came in third, but he did not get a first-place votes the judges. Orlando ranked fourth star Howard scored three first-place votes. MVP Award this season, a step towards innovation - the first time fans can be voted MVP. Web site by logging NBA fans, selected from five candidates for their own favorite MVP. However, the sum of all the fans to vote the final vote only in the official vote count a ballot paper. Not surprisingly, James has also gained fans to vote first 中文 来源:新华社2023-07-23 05:54:121
They were the only men who received votes ______me.
选D,意思是他们是除我之外唯一得到选票的人。2023-07-23 05:54:211
Had Paul received six more votes in the last election,he would have been our chairman now. 改错
很简单:Had Paul received six more votes in the last election,he would be our chairman now.后一个从句指现在,所以虚拟语气只能用would be,而不是用于过去时的would have been.保证答案正确,请及时采纳.祝学习...2023-07-23 05:54:281
django项目 makemigrations时出现django.db.migrations.graph.nodenotfounderror错误。
1. 创建项目运行下面命令就可以创建一个 django 项目,项目名称叫 mysite :$ django-admin.py startproject mysite创建后的项目目录如下:mysite├── manage.py└── mysite ├── __init__.py ├── settings.py ├── urls.py └── wsgi.py1 directory, 5 files说明:__init__.py :让 Python 把该目录当成一个开发包 (即一组模块)所需的文件。 这是一个空文件,一般你不需要修改它。manage.py :一种命令行工具,允许你以多种方式与该 Django 项目进行交互。 键入python manage.py help,看一下它能做什么。 你应当不需要编辑这个文件;在这个目录下生成它纯是为了方便。settings.py :该 Django 项目的设置或配置。urls.py:Django项目的URL路由设置。目前,它是空的。wsgi.py:WSGI web 应用服务器的配置文件。更多细节,查看 How to deploy with WSGI接下来,你可以修改 settings.py 文件,例如:修改 LANGUAGE_CODE、设置时区 TIME_ZONESITE_ID = 1LANGUAGE_CODE = "zh_CN"TIME_ZONE = "Asia/Shanghai"USE_TZ = True 上面开启了 [Time zone]() 特性,需要安装 pytz:$ sudo pip install pytz2. 运行项目在运行项目之前,我们需要创建数据库和表结构,这里我使用的默认数据库:$ python manage.py migrateOperations to perform: Apply all migrations: admin, contenttypes, auth, sessionsRunning migrations: Applying contenttypes.0001_initial... OK Applying auth.0001_initial... OK Applying admin.0001_initial... OK Applying sessions.0001_initial... OK然后启动服务:$ python manage.py runserver你会看到下面的输出:Performing system checks...System check identified no issues (0 silenced).January 28, 2015 - 02:08:33Django version 1.7.1, using settings "mysite.settings"Starting development server at Quit the server with CONTROL-C.这将会在端口8000启动一个本地服务器, 并且只能从你的这台电脑连接和访问。 既然服务器已经运行起来了,现在用网页浏览器访问 。你应该可以看到一个令人赏心悦目的淡蓝色 Django 欢迎页面它开始工作了。你也可以指定启动端口:$ python manage.py runserver 8080以及指定 ip:$ python manage.py runserver 0.0.0.0:80003. 创建 app前面创建了一个项目并且成功运行,现在来创建一个 app,一个 app 相当于项目的一个子模块。在项目目录下创建一个 app:$ python manage.py startapp polls如果操作成功,你会在 mysite 文件夹下看到已经多了一个叫 polls 的文件夹,目录结构如下:polls├── __init__.py├── admin.py├── migrations│ └── __init__.py├── models.py├── tests.py└── views.py1 directory, 6 files4. 创建模型每一个 Django Model 都继承自 django.db.models.Model在 Model 当中每一个属性 attribute 都代表一个 database field通过 Django Model API 可以执行数据库的增删改查, 而不需要写一些数据库的查询语句打开 polls 文件夹下的 models.py 文件。创建两个模型:import datetimefrom django.db import modelsfrom django.utils import timezoneclass Question(models.Model): question_text = models.CharField(max_length=200) pub_date = models.DateTimeField("date published") def was_published_recently(self): return self.pub_date >= timezone.now() - datetime.timedelta(days=1)class Choice(models.Model): question = models.ForeignKey(Question) choice_text = models.CharField(max_length=200) votes = models.IntegerField(default=0)然后在 mysite/settings.py 中修改 INSTALLED_APPS 添加 polls:INSTALLED_APPS = ( "django.contrib.admin", "django.contrib.auth", "django.contrib.contenttypes", "django.contrib.sessions", "django.contrib.messages", "django.contrib.staticfiles", "polls",)在添加了新的 app 之后,我们需要运行下面命令告诉 Django 你的模型做了改变,需要迁移数据库:$ python manage.py makemigrations polls你会看到下面的输出日志:Migrations for "polls": 0001_initial.py: - Create model Choice - Create model Question - Add field question to choice你可以从 polls/migrations/0001_initial.py 查看迁移语句。运行下面语句,你可以查看迁移的 sql 语句:$ python manage.py sqlmigrate polls 0001输出结果:BEGIN;CREATE TABLE "polls_choice" ("id" integer NOT NULL PRIMARY KEY AUTOINCREMENT, "choice_text" varchar(200) NOT NULL, "votes" integer NOT NULL);CREATE TABLE "polls_question" ("id" integer NOT NULL PRIMARY KEY AUTOINCREMENT, "question_text" varchar(200) NOT NULL, "pub_date" datetime NOT NULL);CREATE TABLE "polls_choice__new" ("id" integer NOT NULL PRIMARY KEY AUTOINCREMENT, "choice_text" varchar(200) NOT NULL, "votes" integer NOT NULL, "question_id" integer NOT NULL REFERENCES "polls_question" ("id"));INSERT INTO "polls_choice__new" ("choice_text", "votes", "id") SELECT "choice_text", "votes", "id" FROM "polls_choice";DROP TABLE "polls_choice";ALTER TABLE "polls_choice__new" RENAME TO "polls_choice";CREATE INDEX polls_choice_7aa0f6ee ON "polls_choice" ("question_id");COMMIT;你可以运行下面命令,来检查数据库是否有问题:$ python manage.py check再次运行下面的命令,来创建新添加的模型:$ python manage.py migrateOperations to perform: Apply all migrations: admin, contenttypes, polls, auth, sessionsRunning migrations: Applying polls.0001_initial... OK总结一下,当修改一个模型时,需要做以下几个步骤:修改 models.py 文件运行 python manage.py makemigrations 创建迁移语句运行 python manage.py migrate,将模型的改变迁移到数据库中你可以阅读 django-admin.py documentation,查看更多 manage.py 的用法。创建了模型之后,我们可以通过 Django 提供的 API 来做测试。运行下面命令可以进入到 python shell 的交互模式:$ python manage.py shell下面是一些测试:>>> from polls.models import Question, Choice # Import the model classes we just wrote.# No questions are in the system yet.>>> Question.objects.all()[]# Create a new Question.# Support for time zones is enabled in the default settings file, so# Django expects a datetime with tzinfo for pub_date. Use timezone.now()# instead of datetime.datetime.now() and it will do the right thing.>>> from django.utils import timezone>>> q = Question(question_text="What"s new?", pub_date=timezone.now())# Save the object into the database. You have to call save() explicitly.>>> q.save()# Now it has an ID. Note that this might say "1L" instead of "1", depending# on which database you"re using. That"s no biggie; it just means your# database backend prefers to return integers as Python long integer# objects.>>> q.id1# Access model field values via Python attributes.>>> q.question_text"What"s new?">>> q.pub_datedatetime.datetime(2012, 2, 26, 13, 0, 0, 775217, tzinfo=<UTC>)# Change values by changing the attributes, then calling save().>>> q.question_text = "What"s up?">>> q.save()# objects.all() displays all the questions in the database.>>> Question.objects.all()[<Question: Question object>]打印所有的 Question 时,输出的结果是 [<Question: Question object>],我们可以修改模型类,使其输出更为易懂的描述。修改模型类:from django.db import modelsclass Question(models.Model): # ... def __str__(self): # __unicode__ on Python 2 return self.question_textclass Choice(models.Model): # ... def __str__(self): # __unicode__ on Python 2 return self.choice_text接下来继续测试:>>> from polls.models import Question, Choice# Make sure our __str__() addition worked.>>> Question.objects.all()[<Question: What"s up?>]# Django provides a rich database lookup API that"s entirely driven by# keyword arguments.>>> Question.objects.filter(id=1)[<Question: What"s up?>]>>> Question.objects.filter(question_text__startswith="What")[<Question: What"s up?>]# Get the question that was published this year.>>> from django.utils import timezone>>> current_year = timezone.now().year>>> Question.objects.get(pub_date__year=current_year)<Question: What"s up?># Request an ID that doesn"t exist, this will raise an exception.>>> Question.objects.get(id=2)Traceback (most recent call last): ...DoesNotExist: Question matching query does not exist.# Lookup by a primary key is the most common case, so Django provides a# shortcut for primary-key exact lookups.# The following is identical to Question.objects.get(id=1).>>> Question.objects.get(pk=1)<Question: What"s up?># Make sure our custom method worked.>>> q = Question.objects.get(pk=1)# Give the Question a couple of Choices. The create call constructs a new# Choice object, does the INSERT statement, adds the choice to the set# of available choices and returns the new Choice object. Django creates# a set to hold the "other side" of a ForeignKey relation# (e.g. a question"s choice) which can be accessed via the API.>>> q = Question.objects.get(pk=1)# Display any choices from the related object set -- none so far.>>> q.choice_set.all()[]# Create three choices.>>> q.choice_set.create(choice_text="Not much", votes=0)<Choice: Not much>>>> q.choice_set.create(choice_text="The sky", votes=0)<Choice: The sky>>>> c = q.choice_set.create(choice_text="Just hacking again", votes=0)# Choice objects have API access to their related Question objects.>>> c.question<Question: What"s up?># And vice versa: Question objects get access to Choice objects.>>> q.choice_set.all()[<Choice: Not much>, <Choice: The sky>, <Choice: Just hacking again>]>>> q.choice_set.count()3# The API automatically follows relationships as far as you need.# Use double underscores to separate relationships.# This works as many levels deep as you want; there"s no limit.# Find all Choices for any question whose pub_date is in this year# (reusing the "current_year" variable we created above).>>> Choice.objects.filter(question__pub_date__year=current_year)[<Choice: Not much>, <Choice: The sky>, <Choice: Just hacking again>]# Let"s delete one of the choices. Use delete() for that.>>> c = q.choice_set.filter(choice_text__startswith="Just hacking")>>> c.delete()>>> 上面这部分测试,涉及到 django orm 相关的知识,详细说明可以参考 Django中的ORM。5. 管理 adminDjango有一个优秀的特性, 内置了Django admin后台管理界面, 方便管理者进行添加和删除网站的内容.新建的项目系统已经为我们设置好了后台管理功能,见 mysite/settings.py:INSTALLED_APPS = ( "django.contrib.admin", #默认添加后台管理功能 "django.contrib.auth", "django.contrib.contenttypes", "django.contrib.sessions", "django.contrib.messages", "django.contrib.staticfiles", "mysite",)同时也已经添加了进入后台管理的 url, 可以在 mysite/urls.py 中查看:url(r"^admin/", include(admin.site.urls)), #可以使用设置好的url进入网站后台接下来我们需要创建一个管理用户来登录 admin 后台管理界面:$ python manage.py createsuperuserUsername (leave blank to use "june"): adminEmail address:Password:Password (again):Superuser created successfully.总结最后,来看项目目录结构:mysite├── db.sqlite3├── manage.py├── mysite│ ├── __init__.py│ ├── settings.py│ ├── urls.py│ ├── wsgi.py├── polls│ ├── __init__.py│ ├── admin.py│ ├── migrations│ │ ├── 0001_initial.py│ │ ├── __init__.py│ ├── models.py│ ├── templates│ │ └── polls│ │ ├── detail.html│ │ ├── index.html│ │ └── results.html│ ├── tests.py│ ├── urls.py│ ├── views.py└── templates └── admin └── base_site.htm 通过上面的介绍,对 django 的安装、运行以及如何创建视 图和模型有了一个清晰的认识,接下来就可以深入的学习 django 的自动化测试、持久化、中间件、国 际 化等知识。2023-07-23 05:54:371
求英语语法高手解惑,..题目如下
同意上面对28,29,34的回答。其它有不同看法:30题答案应该为B.otherwise,otherwise是副词,意为“否则的话”,全句意为:他应该是在工作,否则的话是在忙着。如果用else一般跟or的后面,而but的后面常跟otherwise31.全面有having received...,表明此动作在前,故后面不用to have been33.整个句子都是逗号,所以答案应该是which,其它答案均错,从语法上是不成立的。2023-07-23 05:54:472
IMDB到底是如何评分和排名的?
我这几年下来已经投了快550本电影的票了,不知道算不算regular voters,估计他们看到注册地是中国大陆的就直接无视了2023-07-23 05:54:552
有一部电影是杨千华和梁朝伟演的,梁朝伟扮演一个算命的人,叫赖料布,请问这部电影叫什么名字
me too2023-07-23 05:55:055
请问什么是IMDB评分?
IMDB是目前全球互联网中最大的一个电影资料库,里面包括了几乎所有的电影,以及1982年以后的电视剧集。IMDB的资料中包括了影片的众多信息,演员,片长,内容介绍,分级,评论等,就个人买碟而言,很大程度上也是参考IMDB的得分。 而IMDB的得分又是如何来的呢?它的可靠性又有多少呢?让我们通过《魔戒1:护戒使者》来做具体分析吧,先看上图: 这张图就是魔戒1的所有评分者的分数的一个条状统计图。 从中我们可以看到各个分数段的大致比例,比如这儿就可以发现,超过一半的人是打满分的。 根据IMDB网站上公布的TOP250评分标准: imdb top 250用的是贝叶斯统计的算法得出的加权分(Weighted Rank-WR),公式如下: weighted rank (WR) = (v ÷ (v+m)) × R + (m ÷ (v+m)) × C 其中: R = average for the movie (mean) = (Rating) (是用普通的方法计算出的平均分) v = number of votes for the movie = (votes)(投票人数,需要注意的是,只有经常投票者才会被计算在内,这个下面详细解释) m = minimum votes required to be listed in the top 250 (currently 1250) (进入imdb top 250需要的最小票数,只有三两个人投票的电影就算得满分也没用的) C = the mean vote across the whole report (currently 6.9) (目前所有电影的平均得分) 另外重点来了,根据这个注释: note: for this top 250, only votes from regular voters are considered. 只有‘regular voters‘的投票才会被计算在IMDB top 250之内,这就是IMDB防御因为某种电影的fans拉票而影响 top 250结果,把top 250尽量限制在资深影迷投票范围内的主要方法。regular voter的标准不详,估计至少是“投票电影超过xxx 部以上”这样的水平,搞不好还会加上投票的时间分布,为支持自己的心爱电影一天内给N百部电影投票估计也不行。 因此,细心的人可以注意到,列入IMDB top 250的电影,其主页面上的分数与250列表中的分数是不同的。以魔戒1为例,它在自己的页面http://www.imdb.com/title/tt0120737/中的分数是8.8,而列表中是8.7。一般 250表中的得分都会低于自己页面中的得分,越是娱乐片差距越大。这大概是因为regular voter对于电影的要求通常较高的关系。2023-07-23 05:55:331
share怎么读
山若2023-07-23 05:55:425
If paul had received six more votes in the last election,he?
A 首先在A和B两个选项中选,因为题目已经确定是虚拟句所以肯定是过去时态,而从句是过去完成时态,主句是表示的"现在",所以就是过去时态了.(根据虚拟句的法则,是过去的事情那么从句就用过去的过去即过去完成时态)而B选项的意思是"本该```"的意思,如:you should have finished your homework before supper.你本该在晚饭前完成作业.,2,a 条件句过去时虚拟语气 主句现代时虚拟语气 结构:would + do,2,A 很简单,用不着一堆语法解释。条件句是对过去的假设,主句是对现在的假设,都是虚拟的,就都按照正常时态倒退一个时态就好了。,2,D,2,答案 是 B 因为是对过去条件的 假设 是虚拟语气句型,2,B,2,选择B,过去将来时,俺是凭语感得出答案的,不用说了,你问问老外,肯定是B 如果paul在上次的投票中得到多于6票的选票,那他现在就应该是我们的主席了 这样看看,选什么?,1,A 这是个混合虚拟语气,从句是对过去的虚拟所以用的是had received,而主句是对现在情况的虚拟(用了时间状语now),所以用的是would be。,0,If paul had received six more votes in the last election,he ______ our chairman now. A.would be B.would have been C.will be D.must have been. 请说出选择的理由. 可是我的语感告诉我是B。 我很难理解A的感觉!2023-07-23 05:56:041
急求c语言 dev c++) 利用结构体做一个小系统,为什么直接无法编译运行?
调用mistake函数,不需要加上void2023-07-23 05:56:212
Lo-Pro的《Fuel》 歌词
歌曲名:Fuel歌手:Lo-Pro专辑:Lo-ProArtist - CatatoniaAlbum - Paper Scissors StoneLyrics - Fuel我爱摇滚和唐慧QQ;1015762832Go tell the captainThere"s no waters leftTo navigateI sailed them all for you...Go tell the engine roomStop stoking up the fireWe"re out of fuel...Doom looms large on my horizonMountain toxic, river poisonFools get votes in a democracy...We"ll build new ring roadsTo go nowhere in particularNow you"ve passed your Highway CodeAnd make new inroadsInto plundering the EarthFor some more fuel...Doom looms large on my horizonMountain toxic, river poisonFools get votes in a democracy...Go ask the GovernmentYou voted in on trustWhere is our fuel?...Doom looms large on my horizonMountain toxic, river poisonFools get votes in a democracy...Doom looms large on my horizonMountain toxic, river poisonFools get votes in a democracy...http://music.baidu.com/song/80456202023-07-23 05:56:391
几道英语选折题 帮帮忙
A B D B A A C B应该是这样的吧!^-^2023-07-23 05:56:493
如何创建一个Django网站
本文演示如何创建一个简单的 django 网站,使用的 django 版本为1.7。1. 创建项目运行下面命令就可以创建一个 django 项目,项目名称叫 mysite :$ django-admin.py startproject mysite创建后的项目目录如下:mysite├── manage.py└── mysite ├── __init__.py ├── settings.py ├── urls.py └── wsgi.py1 directory, 5 files说明:__init__.py :让 Python 把该目录当成一个开发包 (即一组模块)所需的文件。 这是一个空文件,一般你不需要修改它。manage.py :一种命令行工具,允许你以多种方式与该 Django 项目进行交互。 键入python manage.py help,看一下它能做什么。 你应当不需要编辑这个文件;在这个目录下生成它纯是为了方便。settings.py :该 Django 项目的设置或配置。urls.py:Django项目的URL路由设置。目前,它是空的。wsgi.py:WSGI web 应用服务器的配置文件。更多细节,查看 How to deploy with WSGI接下来,你可以修改 settings.py 文件,例如:修改 LANGUAGE_CODE、设置时区 TIME_ZONESITE_ID = 1LANGUAGE_CODE = "zh_CN"TIME_ZONE = "Asia/Shanghai"USE_TZ = True 上面开启了 [Time zone](https://docs.djangoproject.com/en/1.7/topics/i18n/timezones/) 特性,需要安装 pytz:$ sudo pip install pytz2. 运行项目在运行项目之前,我们需要创建数据库和表结构,这里我使用的默认数据库:$ python manage.py migrateOperations to perform: Apply all migrations: admin, contenttypes, auth, sessionsRunning migrations: Applying contenttypes.0001_initial... OK Applying auth.0001_initial... OK Applying admin.0001_initial... OK Applying sessions.0001_initial... OK然后启动服务:$ python manage.py runserver你会看到下面的输出:Performing system checks...System check identified no issues (0 silenced).January 28, 2015 - 02:08:33Django version 1.7.1, using settings "mysite.settings"Starting development server at http://127.0.0.1:8000/Quit the server with CONTROL-C.这将会在端口8000启动一个本地服务器, 并且只能从你的这台电脑连接和访问。 既然服务器已经运行起来了,现在用网页浏览器访问 http://127.0.0.1:8000/。你应该可以看到一个令人赏心悦目的淡蓝色 Django 欢迎页面它开始工作了。你也可以指定启动端口:$ python manage.py runserver 8080以及指定 ip:$ python manage.py runserver 0.0.0.0:80003. 创建 app前面创建了一个项目并且成功运行,现在来创建一个 app,一个 app 相当于项目的一个子模块。在项目目录下创建一个 app:$ python manage.py startapp polls如果操作成功,你会在 mysite 文件夹下看到已经多了一个叫 polls 的文件夹,目录结构如下:polls├── __init__.py├── admin.py├── migrations│ └── __init__.py├── models.py├── tests.py└── views.py1 directory, 6 files4. 创建模型每一个 Django Model 都继承自 django.db.models.Model在 Model 当中每一个属性 attribute 都代表一个 database field通过 Django Model API 可以执行数据库的增删改查, 而不需要写一些数据库的查询语句打开 polls 文件夹下的 models.py 文件。创建两个模型:import datetimefrom django.db import modelsfrom django.utils import timezoneclass Question(models.Model): question_text = models.CharField(max_length=200) pub_date = models.DateTimeField("date published") def was_published_recently(self): return self.pub_date >= timezone.now() - datetime.timedelta(days=1)class Choice(models.Model): question = models.ForeignKey(Question) choice_text = models.CharField(max_length=200) votes = models.IntegerField(default=0)然后在 mysite/settings.py 中修改 INSTALLED_APPS 添加 polls:INSTALLED_APPS = ( "django.contrib.admin", "django.contrib.auth", "django.contrib.contenttypes", "django.contrib.sessions", "django.contrib.messages", "django.contrib.staticfiles", "polls",)在添加了新的 app 之后,我们需要运行下面命令告诉 Django 你的模型做了改变,需要迁移数据库:$ python manage.py makemigrations polls你会看到下面的输出日志:Migrations for "polls": 0001_initial.py: - Create model Choice - Create model Question - Add field question to choice你可以从 polls/migrations/0001_initial.py 查看迁移语句。运行下面语句,你可以查看迁移的 sql 语句:$ python manage.py sqlmigrate polls 0001输出结果:BEGIN;CREATE TABLE "polls_choice" ("id" integer NOT NULL PRIMARY KEY AUTOINCREMENT, "choice_text" varchar(200) NOT NULL, "votes" integer NOT NULL);CREATE TABLE "polls_question" ("id" integer NOT NULL PRIMARY KEY AUTOINCREMENT, "question_text" varchar(200) NOT NULL, "pub_date" datetime NOT NULL);CREATE TABLE "polls_choice__new" ("id" integer NOT NULL PRIMARY KEY AUTOINCREMENT, "choice_text" varchar(200) NOT NULL, "votes" integer NOT NULL, "question_id" integer NOT NULL REFERENCES "polls_question" ("id"));INSERT INTO "polls_choice__new" ("choice_text", "votes", "id") SELECT "choice_text", "votes", "id" FROM "polls_choice";DROP TABLE "polls_choice";ALTER TABLE "polls_choice__new" RENAME TO "polls_choice";CREATE INDEX polls_choice_7aa0f6ee ON "polls_choice" ("question_id");COMMIT;你可以运行下面命令,来检查数据库是否有问题:$ python manage.py check再次运行下面的命令,来创建新添加的模型:$ python manage.py migrateOperations to perform: Apply all migrations: admin, contenttypes, polls, auth, sessionsRunning migrations: Applying polls.0001_initial... OK总结一下,当修改一个模型时,需要做以下几个步骤:修改 models.py 文件运行 python manage.py makemigrations 创建迁移语句运行 python manage.py migrate,将模型的改变迁移到数据库中你可以阅读 django-admin.py documentation,查看更多 manage.py 的用法。创建了模型之后,我们可以通过 Django 提供的 API 来做测试。运行下面命令可以进入到 python shell 的交互模式:$ python manage.py shell下面是一些测试:>>> from polls.models import Question, Choice # Import the model classes we just wrote.# No questions are in the system yet.>>> Question.objects.all()[]# Create a new Question.# Support for time zones is enabled in the default settings file, so# Django expects a datetime with tzinfo for pub_date. Use timezone.now()# instead of datetime.datetime.now() and it will do the right thing.>>> from django.utils import timezone>>> q = Question(question_text="What"s new?", pub_date=timezone.now())# Save the object into the database. You have to call save() explicitly.>>> q.save()# Now it has an ID. Note that this might say "1L" instead of "1", depending# on which database you"re using. That"s no biggie; it just means your# database backend prefers to return integers as Python long integer# objects.>>> q.id1# Access model field values via Python attributes.>>> q.question_text"What"s new?">>> q.pub_datedatetime.datetime(2012, 2, 26, 13, 0, 0, 775217, tzinfo=<UTC>)# Change values by changing the attributes, then calling save().>>> q.question_text = "What"s up?">>> q.save()# objects.all() displays all the questions in the database.>>> Question.objects.all()[<Question: Question object>]打印所有的 Question 时,输出的结果是 [<Question: Question object>],我们可以修改模型类,使其输出更为易懂的描述。修改模型类:from django.db import modelsclass Question(models.Model): # ... def __str__(self): # __unicode__ on Python 2 return self.question_textclass Choice(models.Model): # ... def __str__(self): # __unicode__ on Python 2 return self.choice_text接下来继续测试:>>> from polls.models import Question, Choice# Make sure our __str__() addition worked.>>> Question.objects.all()[<Question: What"s up?>]# Django provides a rich database lookup API that"s entirely driven by# keyword arguments.>>> Question.objects.filter(id=1)[<Question: What"s up?>]>>> Question.objects.filter(question_text__startswith="What")[<Question: What"s up?>]# Get the question that was published this year.>>> from django.utils import timezone>>> current_year = timezone.now().year>>> Question.objects.get(pub_date__year=current_year)<Question: What"s up?># Request an ID that doesn"t exist, this will raise an exception.>>> Question.objects.get(id=2)Traceback (most recent call last): ...DoesNotExist: Question matching query does not exist.# Lookup by a primary key is the most common case, so Django provides a# shortcut for primary-key exact lookups.# The following is identical to Question.objects.get(id=1).>>> Question.objects.get(pk=1)<Question: What"s up?># Make sure our custom method worked.>>> q = Question.objects.get(pk=1)# Give the Question a couple of Choices. The create call constructs a new# Choice object, does the INSERT statement, adds the choice to the set# of available choices and returns the new Choice object. Django creates# a set to hold the "other side" of a ForeignKey relation# (e.g. a question"s choice) which can be accessed via the API.>>> q = Question.objects.get(pk=1)# Display any choices from the related object set -- none so far.>>> q.choice_set.all()[]# Create three choices.>>> q.choice_set.create(choice_text="Not much", votes=0)<Choice: Not much>>>> q.choice_set.create(choice_text="The sky", votes=0)<Choice: The sky>>>> c = q.choice_set.create(choice_text="Just hacking again", votes=0)# Choice objects have API access to their related Question objects.>>> c.question<Question: What"s up?># And vice versa: Question objects get access to Choice objects.>>> q.choice_set.all()[<Choice: Not much>, <Choice: The sky>, <Choice: Just hacking again>]>>> q.choice_set.count()3# The API automatically follows relationships as far as you need.# Use double underscores to separate relationships.# This works as many levels deep as you want; there"s no limit.# Find all Choices for any question whose pub_date is in this year# (reusing the "current_year" variable we created above).>>> Choice.objects.filter(question__pub_date__year=current_year)[<Choice: Not much>, <Choice: The sky>, <Choice: Just hacking again>]# Let"s delete one of the choices. Use delete() for that.>>> c = q.choice_set.filter(choice_text__startswith="Just hacking")>>> c.delete()>>> 上面这部分测试,涉及到 django orm 相关的知识,详细说明可以参考 Django中的ORM。5. 管理 adminDjango有一个优秀的特性, 内置了Django admin后台管理界面, 方便管理者进行添加和删除网站的内容.新建的项目系统已经为我们设置好了后台管理功能,见 mysite/settings.py:INSTALLED_APPS = ( "django.contrib.admin", #默认添加后台管理功能 "django.contrib.auth", "django.contrib.contenttypes", "django.contrib.sessions", "django.contrib.messages", "django.contrib.staticfiles", "mysite",)同时也已经添加了进入后台管理的 url, 可以在 mysite/urls.py 中查看:url(r"^admin/", include(admin.site.urls)), #可以使用设置好的url进入网站后台接下来我们需要创建一个管理用户来登录 admin 后台管理界面:$ python manage.py createsuperuserUsername (leave blank to use "june"): adminEmail address:Password:Password (again):Superuser created successfully.总结最后,来看项目目录结构:mysite├── db.sqlite3├── manage.py├── mysite│ ├── __init__.py│ ├── settings.py│ ├── urls.py│ ├── wsgi.py├── polls│ ├── __init__.py│ ├── admin.py│ ├── migrations│ │ ├── 0001_initial.py│ │ ├── __init__.py│ ├── models.py│ ├── templates│ │ └── polls│ │ ├── detail.html│ │ ├── index.html│ │ └── results.html│ ├── tests.py│ ├── urls.py│ ├── views.py└── templates └── admin └── base_site.htm 通过上面的介绍,对 django 的安装、运行以及如何创建视 图和模型有了一个清晰的认识,接下来就可以深入的学习 django 的自动化测试、持久化、中间件、国 际 化等知识。2023-07-23 05:56:581
如何解决Django 1.8在migrate时失败
1. 创建项目运行下面命令就可以创建一个 django 项目,项目名称叫 mysite :$ django-admin.py startproject mysite创建后的项目目录如下:mysite├── manage.py└── mysite├── __init__.py├── settings.py├── urls.py└── wsgi.py1 directory, 5 files说明:__init__.py :让 Python 把该目录当成一个开发包 (即一组模块)所需的文件。 这是一个空文件,一般你不需要修改它。manage.py :一种命令行工具,允许你以多种方式与该 Django 项目进行交互。 键入python manage.py help,看一下它能做什么。 你应当不需要编辑这个文件;在这个目录下生成它纯是为了方便。settings.py :该 Django 项目的设置或配置。urls.py:Django项目的URL路由设置。目前,它是空的。wsgi.py:WSGI web 应用服务器的配置文件。更多细节,查看 How to deploy with WSGI接下来,你可以修改 settings.py 文件,例如:修改 LANGUAGE_CODE、设置时区 TIME_ZONESITE_ID = 1LANGUAGE_CODE = "zh_CN"TIME_ZONE = "Asia/Shanghai"USE_TZ = True 上面开启了 [Time zone](https://docs.djangoproject.com/en/1.7/topics/i18n/timezones/) 特性,需要安装 pytz:$ sudo pip install pytz2. 运行项目在运行项目之前,我们需要创建数据库和表结构,这里我使用的默认数据库:$ python manage.py migrateOperations to perform:Apply all migrations: admin, contenttypes, auth, sessionsRunning migrations:Applying contenttypes.0001_initial... OKApplying auth.0001_initial... OKApplying admin.0001_initial... OKApplying sessions.0001_initial... OK然后启动服务:$ python manage.py runserver你会看到下面的输出:Performing system checks...System check identified no issues (0 silenced).January 28, 2015 - 02:08:33Django version 1.7.1, using settings "mysite.settings"Starting development server at http://127.0.0.1:8000/Quit the server with CONTROL-C.这将会在端口8000启动一个本地服务器, 并且只能从你的这台电脑连接和访问。 既然服务器已经运行起来了,现在用网页浏览器访问 http://127.0.0.1:8000/。你应该可以看到一个令人赏心悦目的淡蓝色 Django 欢迎页面它开始工作了。你也可以指定启动端口:$ python manage.py runserver 8080以及指定 ip:$ python manage.py runserver 0.0.0.0:80003. 创建 app前面创建了一个项目并且成功运行,现在来创建一个 app,一个 app 相当于项目的一个子模块。在项目目录下创建一个 app:$ python manage.py startapp polls如果操作成功,你会在 mysite 文件夹下看到已经多了一个叫 polls 的文件夹,目录结构如下:polls├── __init__.py├── admin.py├── migrations│ └── __init__.py├── models.py├── tests.py└── views.py1 directory, 6 files4. 创建模型每一个 Django Model 都继承自 django.db.models.Model在 Model 当中每一个属性 attribute 都代表一个 database field通过 Django Model API 可以执行数据库的增删改查, 而不需要写一些数据库的查询语句打开 polls 文件夹下的 models.py 文件。创建两个模型:import datetimefrom django.db import modelsfrom django.utils import timezoneclass Question(models.Model):question_text = models.CharField(max_length=200)pub_date = models.DateTimeField("date published")def was_published_recently(self):return self.pub_date >= timezone.now() - datetime.timedelta(days=1)class Choice(models.Model):question = models.ForeignKey(Question)choice_text = models.CharField(max_length=200)votes = models.IntegerField(default=0)然后在 mysite/settings.py 中修改 INSTALLED_APPS 添加 polls:INSTALLED_APPS = ("django.contrib.admin","django.contrib.auth","django.contrib.contenttypes","django.contrib.sessions","django.contrib.messages","django.contrib.staticfiles","polls",)在添加了新的 app 之后,我们需要运行下面命令告诉 Django 你的模型做了改变,需要迁移数据库:$ python manage.py makemigrations polls你会看到下面的输出日志:Migrations for "polls":0001_initial.py:- Create model Choice- Create model Question- Add field question to choice你可以从 polls/migrations/0001_initial.py 查看迁移语句。运行下面语句,你可以查看迁移的 sql 语句:$ python manage.py sqlmigrate polls 0001输出结果:BEGIN;CREATE TABLE "polls_choice" ("id" integer NOT NULL PRIMARY KEY AUTOINCREMENT, "choice_text" varchar(200) NOT NULL, "votes" integer NOT NULL);CREATE TABLE "polls_question" ("id" integer NOT NULL PRIMARY KEY AUTOINCREMENT, "question_text" varchar(200) NOT NULL, "pub_date" datetime NOT NULL);CREATE TABLE "polls_choice__new" ("id" integer NOT NULL PRIMARY KEY AUTOINCREMENT, "choice_text" varchar(200) NOT NULL, "votes" integer NOT NULL, "question_id" integer NOT NULL REFERENCES "polls_question" ("id"));INSERT INTO "polls_choice__new" ("choice_text", "votes", "id") SELECT "choice_text", "votes", "id" FROM "polls_choice";DROP TABLE "polls_choice";ALTER TABLE "polls_choice__new" RENAME TO "polls_choice";CREATE INDEX polls_choice_7aa0f6ee ON "polls_choice" ("question_id");COMMIT;你可以运行下面命令,来检查数据库是否有问题:$ python manage.py check再次运行下面的命令,来创建新添加的模型:$ python manage.py migrateOperations to perform:Apply all migrations: admin, contenttypes, polls, auth, sessionsRunning migrations:Applying polls.0001_initial... OK总结一下,当修改一个模型时,需要做以下几个步骤:修改 models.py 文件运行 python manage.py makemigrations 创建迁移语句运行 python manage.py migrate,将模型的改变迁移到数据库中你可以阅读 django-admin.py documentation,查看更多 manage.py 的用法。创建了模型之后,我们可以通过 Django 提供的 API 来做测试。运行下面命令可以进入到 python shell 的交互模式:$ python manage.py shell下面是一些测试:>>> from polls.models import Question, Choice # Import the model classes we just wrote.# No questions are in the system yet.>>> Question.objects.all()[]# Create a new Question.# Support for time zones is enabled in the default settings file, so# Django expects a datetime with tzinfo for pub_date. Use timezone.now()# instead of datetime.datetime.now() and it will do the right thing.>>> from django.utils import timezone>>> q = Question(question_text="What"s new?", pub_date=timezone.now())# Save the object into the database. You have to call save() explicitly.>>> q.save()# Now it has an ID. Note that this might say "1L" instead of "1", depending# on which database you"re using. That"s no biggie; it just means your# database backend prefers to return integers as Python long integer# objects.>>> q.id1# Access model field values via Python attributes.>>> q.question_text"What"s new?">>> q.pub_datedatetime.datetime(2012, 2, 26, 13, 0, 0, 775217, tzinfo=<UTC>)# Change values by changing the attributes, then calling save().>>> q.question_text = "What"s up?">>> q.save()# objects.all() displays all the questions in the database.>>> Question.objects.all()[<Question: Question object>]打印所有的 Question 时,输出的结果是 [<Question: Question object>],我们可以修改模型类,使其输出更为易懂的描述。修改模型类:from django.db import modelsclass Question(models.Model):# ...def __str__(self): # __unicode__ on Python 2return self.question_textclass Choice(models.Model):# ...def __str__(self): # __unicode__ on Python 2return self.choice_text接下来继续测试:>>> from polls.models import Question, Choice# Make sure our __str__() addition worked.>>> Question.objects.all()[<Question: What"s up?>]# Django provides a rich database lookup API that"s entirely driven by# keyword arguments.>>> Question.objects.filter(id=1)[<Question: What"s up?>]>>> Question.objects.filter(question_text__startswith="What")[<Question: What"s up?>]# Get the question that was published this year.>>> from django.utils import timezone>>> current_year = timezone.now().year>>> Question.objects.get(pub_date__year=current_year)<Question: What"s up?># Request an ID that doesn"t exist, this will raise an exception.>>> Question.objects.get(id=2)Traceback (most recent call last):...DoesNotExist: Question matching query does not exist.# Lookup by a primary key is the most common case, so Django provides a# shortcut for primary-key exact lookups.# The following is identical to Question.objects.get(id=1).>>> Question.objects.get(pk=1)<Question: What"s up?># Make sure our custom method worked.>>> q = Question.objects.get(pk=1)# Give the Question a couple of Choices. The create call constructs a new# Choice object, does the INSERT statement, adds the choice to the set# of available choices and returns the new Choice object. Django creates# a set to hold the "other side" of a ForeignKey relation# (e.g. a question"s choice) which can be accessed via the API.>>> q = Question.objects.get(pk=1)# Display any choices from the related object set -- none so far.>>> q.choice_set.all()[]# Create three choices.>>> q.choice_set.create(choice_text="Not much", votes=0)<Choice: Not much>>>> q.choice_set.create(choice_text="The sky", votes=0)<Choice: The sky>>>> c = q.choice_set.create(choice_text="Just hacking again", votes=0)# Choice objects have API access to their related Question objects.>>> c.question<Question: What"s up?># And vice versa: Question objects get access to Choice objects.>>> q.choice_set.all()[<Choice: Not much>, <Choice: The sky>, <Choice: Just hacking again>]>>> q.choice_set.count()3# The API automatically follows relationships as far as you need.# Use double underscores to separate relationships.# This works as many levels deep as you want; there"s no limit.# Find all Choices for any question whose pub_date is in this year# (reusing the "current_year" variable we created above).>>> Choice.objects.filter(question__pub_date__year=current_year)[<Choice: Not much>, <Choice: The sky>, <Choice: Just hacking again>]# Let"s delete one of the choices. Use delete() for that.>>> c = q.choice_set.filter(choice_text__startswith="Just hacking")>>> c.delete()>>> 上面这部分测试,涉及到 django orm 相关的知识,详细说明可以参考 Django中的ORM。5. 管理 adminDjango有一个优秀的特性, 内置了Django admin后台管理界面, 方便管理者进行添加和删除网站的内容.新建的项目系统已经为我们设置好了后台管理功能,见 mysite/settings.py:INSTALLED_APPS = ("django.contrib.admin", #默认添加后台管理功能"django.contrib.auth","django.contrib.contenttypes","django.contrib.sessions","django.contrib.messages","django.contrib.staticfiles","mysite",)同时也已经添加了进入后台管理的 url, 可以在 mysite/urls.py 中查看:url(r"^admin/", include(admin.site.urls)), #可以使用设置好的url进入网站后台接下来我们需要创建一个管理用户来登录 admin 后台管理界面:$ python manage.py createsuperuserUsername (leave blank to use "june"): adminEmail address:Password:Password (again):Superuser created successfully.总结最后,来看项目目录结构:mysite├── db.sqlite3├── manage.py├── mysite│ ├── __init__.py│ ├── settings.py│ ├── urls.py│ ├── wsgi.py├── polls│ ├── __init__.py│ ├── admin.py│ ├── migrations│ │ ├── 0001_initial.py│ │ ├── __init__.py│ ├── models.py│ ├── templates│ │ └── polls│ │ ├── detail.html│ │ ├── index.html│ │ └── results.html│ ├── tests.py│ ├── urls.py│ ├── views.py└── templates└── admin└── base_site.htm2023-07-23 05:57:061
for 和foreach分别用于什么场合?
二者有时可以互换,但要注意循环删除的话只能用for语句2023-07-23 05:50:436
电脑装完系统,开机出现管理员命令提示符c:usersadministrator> 怎么办?
关键是看不懂怎么格式化2023-07-23 05:50:442
韩国综艺节目Happy Together的节目表,还有有哪些嘉宾?最好是至今为止所有的~
09年2月26日happy together金贤重,具惠善,金俊,金圭钟,(花样男子特辑)09年1月29日happy together朴龙河,朴艺珍。。。 100204 Happy together 金钟民 NRG 秀根 100211Happy together 金钟国 李胜基等 100325 Happy together 文根英 千正民等 100402 Happy together 文根英 千正民等 100513 Happy together 李孝利 rain 具荷拉 李准等 100520 Happy together 李孝利 rain 具荷拉 李准 2PM等 100610 Happy together wonder girls等 100624 Happy together 利特 恩赫 柳真 允时云等 100722 Happy together 郑容和 孙丹菲等 100805 Happy together 神童 黄静茵 智研等 只查到这些啦、不好意思2023-07-23 05:50:442
抗微生物药物有哪些
阿莫西林,头孢拉定,克拉霉素,氧氟沙星.....挺多的2023-07-23 05:50:462
win7 怎么加入到 PATH environment?
在吗,问题已经2个月了,还需要回答吗?那我就还是答一下吧,其实说的就是把那个路径加到系统的环境变量中去。具体步骤就是:1.随便打开一个文件夹,在左侧导航树里找到“此电脑”右键属性(或者直接桌面我的电脑右键属性)2.在打开的属性页面,找“高级系统设置”点击,win10/win7位置不同,但都在该页面。3.在弹出的窗口里找“环境变量”点击,这个位置绝对都一样的。4.在弹出的变量窗口,找下面栏里的Path这一条双击,如图所示。5.然后弹出的编辑页面win10和win7会不同,win7需要把路径加入其中,一般就放在最后面即可(鼠标点一下编辑框里的内容然后按键盘上end键,光标就自动到最后了,然后就输入你的路径就可以了,记得路径与前面一个路径之间要有分号;最后也加一个分号),win10就直接新增一条输入你的路径即可,没有分号什么的。之后保存确认依次确认即可。楼主所说的第6步无需理会,这样手动操作更稳妥一点。2023-07-23 05:50:411
亲们,我想考研(日语笔译研究生),谁知道招收日语笔译硕士的学校啊,
南京外国语大学2023-07-23 05:50:405
燕赵警民通阳光警务执法办案查询系统在哪?
怎么查询案件进展?2023-07-23 05:50:3714
foreach中文是什么意思
为每一个,具体还得看上下文,望采纳2023-07-23 05:50:342