小伙伴儿们有福啦,2015年4月10日,Hadley Wickham大牛(开发了著名的ggplots包和plyr包等)和RStudio小组又出新作啦,新作品readr包和readxl包分别用于R读取text数据和Excel电子表格数据.事实上,R已经有了一堆读取数据的函数,比如read.table家族以及其巨多的变形,那么为了牛牛们为什么还要开发这两个包呢?原因很简单,这两个包的读取速度比R内置数据读入函数更快!!!记住哦,是快很多哈!不信,我们下来试试就知道啦!哈哈!平时读取小数据的童鞋可能不…

目录 Importing data in R 学习笔记1 flat files:CSV txt文件 packages:readr read_csv() read_tsv read_delim() data.table() fread readxl excel_sheets() read_excel() gdata read.xls() getSheets() XLConnect loadWorkbook() readWorksheet() createSheet() writeWorksheet…

这个报错网上搜索了一下,大部分是由于MySQL意外关闭或强制重启造成的binlog文件事务点读取异常造成的主从同步报错 Last_IO_Error: Got fatal error 1236 from master when reading data from binary log: 'binlog truncated in the middle of event; consider out of disk space on master; the last event was read fro…

本地MySQL环境,是两台MySQL做M-M复制.今天发现错误信息: mysql 5.5.28-log> show slave status\G *************************** 1. row ***************************                Slave_IO_State:                   Master_Host: 88.88.88.88                   Master_User: replicate…

mysql> show slave status\G *************************** 1. row ***************************                Slave_IO_State:                    Master_Host: 10.122.41.208                   Master_User: replication                   Master_Port: 3306    …

/*Author: Jiangong SUN*/ As I've manipulated a lot of data using SQL data reader in recent project. And people says it's not good to access the data by column name. So I've made an performance test in reading data from SQL data reader. Firstly, I've…

Querying or Reading Data OpenTSDB offers a number of means to extract data such as CLI tools, an HTTP API and as a GnuPlot graph. Querying with OpenTSDB's tag based system can be a bit tricky so read through this document and checkout the following p…

从库报这个错误:Got fatal error 1236 from master when reading data from binary log: 'Could not find first log file name in binary log index file' Got fatal error 1236 from master when reading data from binary log: 'could not find next log' 可以 stop slave; res…

年后回来查看mysql运行状况与备份情况,登录mysql从库查看主从同步状态 mysql> show slave status\G; *************************** . row *************************** Slave_IO_State: Master_Host: 101.200.*.* Master_User: backup Master_Port: Connect_Retry: Master_Log_File: master-bin. Rea…

6 ways of mean-centering data in R 怎么scale我们的数据? 还是要看我们自己数据的特征. 如何找到我们数据的中心? Cluster analysis with K-means. How to get the cluster representatives? 开发工具时不要先写代码,把算法理顺了再写,就会顺利得多. 1. 随机或者自定义一个点(基因),找到另一个符合条件的点(距离以及overlap数达标): 2. 算出新的group的中心,找下一个符合条件的点…

1:停止slave服务器的主从同步 stop slave; 2:对Master数据库加锁 flush tables with read lock; 3:备份Master上的数据 mysqldump -uroot -p -B db1 db2 >bak.sql 4:重置Master服务 reset master; reset master 将删除所有的二进制日志,创建一个名为  ****.000001的空日志文件.reset master 并不会影响slave服务器的工作状态.盲目执行这个命令有可能…

刚处理完“挖矿”事件,在做最后一个MySQL NBU备份的时候,发现从库有问题,好奇的是怎么主从状态异常没有告警呢?先不管这么多了,处理了这个问题再完善告警内容. 一.错误信息 从库show slave status \G看到的错误信息如下: Slave_IO_Running: No Slave_SQL_Running: Yes Last_IO_Errno: Last_IO_Error: Got fatal error ' at 4.' 二.错误原因 这里看到从库的io_thread已经终止,错…

setup slave from backup i got error Got fatal error 1236 from master when reading data from binary log: 'Could not find first log file name in binary log index file' MASTER MariaDB [(none)]> SHOW BINLOG EVENTS IN 'mysqld-bin.140180' FROM 101070557 LI…

1) 熟悉CEL file 从 NCBI GEO (http://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE24460)下载GSE24460. 将得到一个 GSE24460_RAW.tar 文件,解压.产生CEL文件,包含各种信息. if("affy" %in% rownames(installed.packages()) == FALSE) {source("http://bioconductor.org/biocLite.…

目录 R 中清洗数据 常见三种查看数据的函数 Exploring raw data 使用dplyr包里面的glimpse函数查看数据结构 \(提取指定元素 ```{r} # Histogram of BMIs from 2008 hist(bmi\)Y2008) Scatter plot comparing BMIs from 1980 to those from 2008 Introduction to tidyr gather() spread() spreate() unite() 常见数…

在source那边,执行: flush logs;show master status; 记下File, Position. 在target端,执行: CHANGE MASTER TO MASTER_LOG_FILE='testdbbinlog.000008',MASTER_LOG_POS=107;slave start;show slave status \G 一切正常. 参考:https://blog.csdn.net/edwzhang/article/details/17226975---…

reset slave会清除从库的所有复制信息.一般应用场景:如切换为不同的Master, 主从重做等: 1. 命令在slave上执行,执行前一定要stop slave. 2. 执行reset slave后,会清除复制相关的所有信息,包括:master.info, relay-log.info, 及无条件删除所有的中继日志(relay logs). 注意是无条件的,也就是不管理你Slave SQL线程是否把所有的relay log重放完了. 3. 注意,stop slave后,先保存show s…

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首先遇到这个是因为binlog位置索引处的问题,不要reset slave: reset slave会将主从同步的文件以及位置恢复到初始状态,一开始没有数据还好,有数据的话,相当于重新开始同步,可能会出现一些问题: 一般做主从同步,都是要求以后的数据实现主从同步,而对于旧的数据完全可以使用数据库同步工具先将数据库同步,完了再进行主从同步: 好了遇到上面的问题,正确做法是: 1.打开主服务器,进入mysql 2.执行flush logs://这时主服务器会重新创建一个binlog文件: 3.在主服…

本文由雪晴数据网负责翻译整理,原文请参考New packages for reading data into R - fast作者David Smith.转载请注明原文链接http://www.xueqing.tv/cms/article/102 昨天在新电脑使用xlsx包的时候,因为加载rJava十分不悦-于是用了readxl,不要太方便,于是转一篇过来备用着.以后读入都用你了~ Hadley Wickham 和 RStudio团队写了一些新的R包,这些包对于每个需要在R中读入数据的人来说都是…

Reading Data There are a few principal functions reading data into R. read.table, read.csv, for reading tabular data readLines, for reading lines of a text file source, for reading in R code files (inverse of dump) dget, for reading in R code files (…

dplyr and data.table are amazing packages that make data manipulation in R fun. Both packages have their strengths. While dplyr is more elegant and resembles natural language, data.table is succinct and we can do a lot withdata.table in just a single…

Recently we were building a Shiny App in which we had to load data from a very large dataframe. It was directly impacting the app initialization time, so we had to look into different ways of reading data from files to R (in our case customer provide…

Around September of 2016 I wrote two articles on using Python for accessing, visualizing, and evaluating trading strategies (see part 1 and part 2). These have been my most popular posts, up until I published my article on learning programming langua…

When working with big data with R (say, using Spark and sparklyr) we have found it very convenient to keep data handles in a neat list ordata_frame. Please read on for our handy hints on keeping your data handles neat. When using R to work over a big…

东莞市 东莞城市标志 东莞城市标志 1985年,广东省东莞县经国务院批准列为珠江三角洲经济开发区,同年9月撤消东莞县,建立(县级)东莞市,1988年1月升格为地级市.东莞市是全国五个不设市辖区的地级市之一,直属广东省.行政区划代码:441900,区号:0769 .截至2011年10月10日,东莞市辖32个镇(街道):其中包括4个街道(莞城街道.南城街道.东城街道.万江街道):28个镇(石碣镇.石龙镇.茶山镇.石排镇.企石镇.横沥镇.桥头镇.谢岗镇.东坑镇.常平镇.寮步镇.大朗镇.黄江镇.清溪镇.…

Machine learning is a branch in computer science that studies the design of algorithms that can learn. Typical machine learning tasks are concept learning, function learning or “predictive modeling”, clustering and finding predictive patterns. These…

[怪毛匠子整理] 1.下载 wget http://mirror.bjtu.edu.cn/cran/src/base/R-3/R-3.0.1.tar.gz 2.解压: tar -zxvf R-3.0.1.tar.gz cd R-3.0.1 3.安装 yum install readline-devel yum install libXt-devel ./configure 如果使用rJava需要加上 --enable-R-shlib ./configure  --enable-R-shlib -…

1.R数据的保存与加载 可通过save()函数保存为.Rdata文件,通过load()函数将数据加载到R中. > a <- 1:10 > save(a,file='d://data//dumData.Rdata') > rm(a)   #将对象a从R中删除 > load('d://data//dumData.Rdata') > print(a) [1]  1  2  3  4  5  6  7  8  9 10 2.CSV文件的导入与导出 下面创建df1的数据框,通过函…

R in Nutshell 前言 例子(nutshell包) 本书中的例子包括在nutshell的R包中,使用数据,需加载nutshell包 install.packages("nutshell") 第一部分:基础 第一章 批处理(Batch Mode) R provides a way to run a large set of commands in sequence and save the results to a file. 以batch mode运行R的一种方式是:使用系统…