starts_with(x, ignore.case = TRUE) # column/variable start with chart x ends_with(x, ignore.case = TRUE) # column/variable end with chart x contains(x, ignore.case = TRUE) # column/variable contains chart x matches(x, ignore.case = TRUE) # column/variable matches regular expression ...
因此可以使用sapply函数)sapply(test,mean) #输出形式是矩阵 x y z 34.5 33.5 28.5 五、数据框的链接(dplyr包)数据设置 test1 <- data.frame(name = c('jimmy','nicker','Damon','Sophie'), blood_type = c("A","B" ,相同的会被合并,空的数据为NA)left_join(test1,test2,by="name") ...
select()filter()mutate()group_by()arrange() 1)数据框列名的重新命名:names(),colnames(),rename() R base对列名进行修改的话,使用如下格式, # R basenames(df)[2]<-c('popularity')# dplyrdf<-df%>%rename(popularity=score) 2)数据过滤:which(),filter() # R basedf[which(df$popularity>3),]...
select()filter()mutate()group_by()arrange() 1)数据框列名的重新命名:names(),colnames(),rename() R base对列名进行修改的话,使用如下格式, # R base names(df)[2] <- c('popularity') # dplyr df <- df %>% rename(popularity = score) 2)数据过滤:which(),filter() # R base df[which(d...
dplyr: A grammar of data manipulation. Contribute to tidyverse/dplyr development by creating an account on GitHub.
group_by(), arrange(), rename(), select(), and distinct() ) and adds some of its own advanced verbs. It is similar to dplyr‘s now-deprecated “SE verbs”, but with a more array and list oriented interface (de-emphasizing use of “ ...” in function arguments). For examp...
rename_at() on a whim, just to get exactly the same output as before, but it is not really necessary): grouped_mean <- function(data, grouping_variables, value_variables) { data %>% group_by_at(grouping_variables) %>% mutate(count = n()) %>% summarise_at(c(value_variables, "co...
我们可以使用 rename 函数,重命名数据框中的某个变量。此外 我们还可以使用 rename_all、rename_at、rename_if 函数,对所有 变量、对某些变量、对满足特定条件的变量进行重命名。 为了更好的在普通数据框与 tibble 类型的数据框之间转换,我们 可以将行名转化为一个单独的变量。使用 rownames_to_column、 column_...
Whencolumn-binding,rowsarematchedbyposition,notvaluesoalldata framesmusthavethesamenumberofrows.Tomatchbyvalue,notposition, seeleft_joinetc.Whenrow-binding,columnsarematchedbyname,andany valuesthatdon’tmatchwillbefilledwithNA. Value bind_rowsandbind_colsalwaysreturnatbl_df Deprecatedfunctions rbind_list...
()operate on a subset of columns. These columuns are selected with either a character vector of columns names, a numeric vector of column positions, or a column specification withselect()semantics generated by the newcolumns()helper. In addition,summarise_if()andmutate_if()take a predicate ...