Temporal | 易学教程

datetime matlab different temporal resolution

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问题 I am trying to plot two timeseries in one graph. Unfortunatelly, the data sets have different temporal resolutions and my code using datetime does not work. My aim is one xtick per hour. Any idea how I can solve that problem? Thanks! dataset1 = rand(1,230).'; dataset2 = rand(1,33).'; xstart = datenum('19/02 09:00','dd/mm HH:MM'); xend = datenum('21/02 18:00','dd/mm HH:MM'); x = linspace(xstart,xend,20); Dat = linspace(xstart,xend,numel(dataset1)); x1=[1:1:230].' %values every 15 minutes x0_OM

Load Historical data to teradata temporal table

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问题 I have a task to load existing SQL Server table to Teradata temporal table. Existing table is a type 2 table and has many versions of record. I need to load them into teradata temporal table. I am planning to load version 1 1st and then update all other versions one by one. Difficulties i am having is that in existing table every record has start time and end time. I need to update that time in teradata temporal table as validity. 1st I am trying to insert and while insert i am not able to

How to use HeidelTime temporal tagger inside a Java project?

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问题 I would like to automatically identify dates inside a stream of documents and in this sense I would like to use the code provided by the open source project Heideltime, available here (https://code.google.com/p/heideltime/). I have installed the Heideltime kit (not the standalone version) and now I am wondering how can I reference it and call it inside my Java project. I have already added a dependecy to Heideltime inside my pom.xml: <dependency> <groupId>de.unihd.dbs</groupId> <artifactId

How to retrieve all kinds of dates and temporal values from text

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问题 I wanted to retrieve dates and other temporal entities from a set of Strings. Can this be done without parsing the string for dates in JAVA as most parsers deal with a limited scope of input patterns. But input is a manual entry which here and hence ambiguous. Inputs can be like: 12th Sep |mid-March |12.September.2013 Sep 12th |12th September| 2013 Sept 13 |12th, September |12th,Feb,2013 I've gone through many answers on finding date in Java but most of them don't deal with such a huge scope

SQL construct and renew date intervals for entities based on daily incoming data

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问题 I have a daily incoming data with following format: (id, dat, state, val) where id is unique entity, dat is date (i.e. ISO 'yyyy-MM-dd'), state is a state of an entity, val is a value of an entity at this state. I need to transform it into data like that format: (id, state, val, dat1, dat2, month) where dat1 and dat2 are datestamps between which the entity id has state state with val value within month. I'm struggling to find out a correct way to collect and persist data like this format. I

Merge update Temporal

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问题 Existing data in table test : (Temporal table) id name valid_dt 1 cat 2012-06-16 - 9999-12-31 Incoming Table : (Temporal) id name valid_dt 1 bat 2013-12-28 - 9999-12-31 After Merge update , test table should have id name valid_dt 1 cat 2012-06-16 - 2013-12-28 1 bat 2013-12-28 - 9999-12-31 Will It be possible in Teradata Temporal Merge update statement if i run it today? non working code i tried SEQUENCED VALIDTIME MERGE INTO test USING ( sel * from incoming ) H on id=H.id when matched then

C# SqlConnection Querying Temporal tables

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问题 I have a temporal table Employee with EmployeeHistory as its history table. In C#, I am using SqlConnection to query the data from SQL Server for the entire history of an employee. var data = Conn.ExecuteReader("select * from Employee e FOR SYSTEM_TIME ALL WHERE e.Id=15"); This throws the error: Incorrect syntax near FOR So, how do we query history data for a temporal table in C# using SqlConnection ? 回答1: Problem is you are using table alias e and so the error. Don't think you can use table

Grouping of Event Time Data based on multiple, iterative conditions

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问题 I have a dataset of ~190,000 rows which includes: Sample Data: found here: > df[1:100,1:6] AcousticTagCode Species SiteCode StartDetection EndDetection Duration_min 1 5004.24 Striped Bass RGD1 2014-10-01 23:01:12.12 2014-10-01 23:59:41.41 58.488167 2 5004.24 Striped Bass RGD1 2014-10-02 00:00:06.06 2014-10-02 01:00:00.00 59.892167 3 5004.24 Striped Bass RGD1 2014-10-02 01:00:01.01 2014-10-02 01:20:12.12 20.185167 4 5004.24 Striped Bass RGD1 2014-10-02 04:14:15.15 2014-10-02 04:32:16.16 18

Creating unique groups in sequential data that repeats through time

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问题 This kind of thing has been asked before, but not quite in this way that I can find. Thread about creating sequential IDs, with several additional links It's not hard to create identifiers in a sequence, but my data includes a temporal element that has thrown me for a loop. The following data is an imaginary dataset just to illustrate the problem in something tractable: dput(walking_dat) structure(list(neighborhood = structure(c(3L, 3L, 3L, 3L, 3L, 2L, 2L, 2L, 2L, 2L, 1L, 1L, 1L), .Label = c(

JavaWeb网站性能优化的相关技术

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一、提高服务器并发处理能力我们总是希望一台服务器在单位时间内能处理的请求越多越好，这也成了web服务器的能力高低的关键所在。服务器之所以可以同时处理多个请求，在于操作系统通过多执行流体系设计，使得多个任务可以轮流使用系统资源，这些资源包括CPU、内存以及I/O等。这就需要选择一个合适的并发策略来合理利用这些资源，从而提高服务器的并发处理能力。这些并发策略更多的应用在apache、nginx、lighttpd等底层web server软件中。二、Web组件分离这里所说的web组件是指web服务器提供的所有基于URL访问的资源，包括动态内容，静态网页，图片，样式表，脚本，视频等等。这些资源在文件大小，文件数量，内容更新频率，预计并发用户数，是否需要脚本解释器等方面有着很大的差异，对不同特性资源采用能充分发挥其潜力的优化策略，能极大的提高web站点的性能。例如：将图片部署在独立的服务器上并为其分配独立的新域名，对静态网页使用epoll模型可以在大并发数情况下吞吐率保持稳定。三、数据库性能优化和扩展。 Web服务器软件在数据库方面做的优化主要是减少访问数据库的次数，具体做法就是使用各种缓存方法。也可以从数据库本身入手提高其查询性能，这涉及到数据库性能优化方面的知识本文不作讨论。另外也可以通过主从复制，读写分离，使用反向代理，写操作分离等方式来扩展数据库规模，提升数据库服务能力。四