我想将列表转换为列表列表.例:
my_list = ['banana', 'mango', 'apple']
我想要:
my_list = [['banana'], ['mango'], ['apple']]
我试过了:
list(list(my_list))
我试图在R中安装MySQL包但无法正确安装包.这是我用过的代码
install.packages('RMySQL',type='source')
我得到的错误就像
Installing package into ‘C:/Users/Techrains/Documents/R/win-library/3.1’
(as ‘lib’ is unspecified)
trying URL 'http://ftp.iitm.ac.in/cran/src/contrib/RMySQL_0.9-3.tar.gz'
Content type 'application/x-gzip' length 165363 bytes (161 Kb)
opened URL
downloaded 161 Kb
* installing *source* package 'RMySQL' ...
** package 'RMySQL' successfully unpacked and MD5 sums checked
Warning: running command 'sh ./configure.win' had status 127
ERROR: configuration failed for package 'RMySQL'
* removing 'C:/Users/Techrains/Documents/R/win-library/3.1/RMySQL'
The downloaded source packages are in
‘C:\Users\Techrains\AppData\Local\Temp\Rtmp8ihccf\downloaded_packages’
Warning messages:
1: running command '"C:/PROGRA~1/R/R-31~1.1/bin/i386/R" CMD INSTALL -l "C:\Users\Techrains\Documents\R\win-library\3.1" C:\Users\TECHRA~1\AppData\Local\Temp\Rtmp8ihccf/downloaded_packages/RMySQL_0.9-3.tar.gz' had status 1 …我有一个具有一列的数据框，一列有一些数据和一些空单元格。当我检查该列的级别时，它显示了三个级别，因为它将空单元格作为一个级别。我要删除该级别。假设我有
df <- data.frame(fan = c("a","b"," ","a","b"))
我已经尝试过此代码
droplevels(df)
但它不起作用。
我正在尝试使用R转换我的数据框格式.我想要唯一的公司名称,因为它对每个公司都有多个观察结果.我的数据看起来像
company name Values Year
A 1 2010
A 2 2011
B 4 2010
B 6 2012
C 8 2011
我想要下面的格式
company name first_value First_year second_values second_year
A 1 2010 2 2011
B 4 2010 6 2012
C 8 2011 NA NA
我已经尝试过这段代码,但它没有给出我期待的结果
library(plyr)
extract.hashtags <- function(x) {
x <- subset(x,select=c(-Company.Name))
mat <- as.matrix(x)
dim(mat) <- c(1,length(mat))
as.data.frame(mat)
}
df1 = ddply(data, .(Company.Name), extract.hashtags )