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安装与介绍

# install.packages('tidyverse', repos = "https://mirrors.tuna.tsinghua.edu.cn/CRAN/")
library(tidyverse)

── Attaching packages ──────────────────────────────────── tidyverse 1.3.0 ──
✓ ggplot2 3.3.0     ✓ purrr   0.3.3
✓ tibble  3.0.0     ✓ dplyr   0.8.5
✓ tidyr   1.0.2     ✓ stringr 1.4.0
✓ readr   1.3.1     ✓ forcats 0.5.0
── Conflicts ─────────────────────────────────────── tidyverse_conflicts() ──
x dplyr::filter() masks stats::filter()
x dplyr::lag()    masks stats::lag()

管道操作符

图片alt

cjb <- read.csv("/home/wy/Downloads/cjb.csv",
                header = TRUE,
                stringsAsFactors = FALSE,
                fileEncoding = "UTF-8")
cjb %>% head
head(cjb) # 同上
cjb %>% head(n=3) # cjb 默认为第一个参数
head(cjb,n=3) # 同上

dplyr包使用

模拟数据下载

图片alt

选择列

cjb %>% 
  select(xm,yw,sx) %>%
  set_names(c('姓名','语文','数学')) %>%
  head(n=3)
# 姓名 语文 数学
# 1   周黎 94 82
# 2 汤海明 87 94
# 3 舒江辉 92 79

cjb %>%
  select(1,4:12) %>%
  head(n=3)
cjb %>%
  select(xm,yw:sw) %>%
  head(n=3)
# xm yw sx wy zz ls dl wl hx sw
# 1   周黎 94 82 96 97 97 98 95 94 88
# 2 汤海明 87 94 89 95 94 94 90 90 89
# 3 舒江辉 92 79 86 98 95 96 89 94 87

增加或者修改列

cjb %>%
  # 将bj,xb,wlfk转化因子
  mutate_at(vars(bj,xb,wlfk),factor) %>% 
  # 求出.(表示前面对象)的4~12列总和
  mutate(zcj = rowSums(.[4:12])) %>%
  # 根据zcj降序排序
  arrange(desc(zcj)) %>%
  # 查看最后两行
  tail(n=2)

注意以上操作原数据没有修改, 如果要修改, 使用 %<>% 或者赋值给原变量 <-

选择行

cjb %>%
  filter(yw<60) # yw小于60

cjb %>%
  # 4~12小于60的行
    filter_at(vars(4:12),any_vars(. < 60))

分组统计

cjb %>%
  mutate(zcj = rowSums(.[4:12])) %>%
  filter(zcj !=0) %>%
  group_by(xb) %>% # 基于xb分组
  summarise(count=n(),
            max = max(zcj),
            mean = mean(zcj),
            min = min(zcj))
# A tibble: 2 x 5
# xb    count   max  mean   min
# <chr> <int> <dbl> <dbl> <dbl>
#   1 女      406   879  797.   647
#   2 男      368   885  793.   523

长宽变换

由于分组变量是列变量

图片alt

cjb %>%
  mutate(zcj = rowSums(.[4:12])) %>%
  filter(zcj !=0) %>%
  group_by(xb) %>% # 基于xb分组
  summarise(count=n(),
            max = max(zcj),
            mean = mean(zcj),
            min = min(zcj))
# A tibble: 2 x 5
# xb    count   max  mean   min
# <chr> <int> <dbl> <dbl> <dbl>
#   1 女      406   879  797.   647
#   2 男      368   885  793.   523

cjb %>% 
  mutate(zcj = rowSums(.[4:12])) %>%
  filter(zcj!=0) %>%
  gather(key = ke_mu,value = cheng_ji,yw:sw) %>%
  group_by(ke_mu) %>%
  summarise(max = max(cheng_ji),
            mean = mean(cheng_ji),
            median =median(cheng_ji),
            min = min(cheng_ji)) %>%
  arrange(desc(mean))
# A tibble: 9 x 5
# ke_mu   max  mean median   min
# <chr> <int> <dbl>  <dbl> <int>
# 1 dl      100  93.0     94    70
# 2 zz      100  92.3     93    65
# 3 hx      100  91.7     94    52
# 4 ls      100  89.1     90     0
# 5 wy       99  87.5     88    30
# 6 yw       96  87.4     88    33
# 7 sw      100  86.4     88    55
# 8 sx      100  86.2     89    26
# 9 wl      100  81.2     83    21

x <- formula(". ~ Species")
aggregate(x, data = iris, mean)
subset(iris,Species=="setosa",select="Petal.Width")[[1]] |>mean()

删除重复行

# 根据所有列删除重复的行(完全一样的观测值)：
my_data %>% distinct()
# 根据特定列删除重复值
my_data %>% distinct(Sepal.Length, .keep_all = TRUE)
# 根据多列删除重复值
my_data %>% distinct(Sepal.Length, Petal.Width, .keep_all = TRUE)
# 选项.kep_all用于保留数据中的所有变量

注: 本文是学堂在线的笔记

library(tidyverse)

fun <- function(x,y){
    cat(x,"---")
    str_remove_all(x,y)
}

read_csv("data/GSE168152_hAFs_EV_miRNA_Profile_UMIcounts.csv.gz")[1:5,1:5]  |>
    column_to_rownames("miRNA") |>
    mutate_all(fun)

read_csv("data/GSE168152_hAFs_EV_miRNA_Profile_UMIcounts.csv.gz")[1:5,1:5]  |>
    column_to_rownames("miRNA") |>
    mutate_all(~fun(.,"\'"))

separate_rows

targetScan_all <-  Predicted_Targets_Info |> 
    filter(SpeciesID==9606) |> 
    separate_rows(miRFamily,sep="/") |>
    mutate(miRNA_symbol=case_when(
        grepl("miR",miRFamily)~paste0("hsa-",miRFamily),
        T~paste0("hsa-miR-",miRFamily)
        )) |>
    dplyr::select(GeneSymbol,miRNA_symbol) |> 
                distinct() |>

R语言去除特定列中含有NA的行

library(tidyr)
# 去除表格DE_GENE 中  colnames为gene_id 的列中含有NA的行
DE_GENE <- DE_GENE %>% drop_na(gene_id)

str_split

using strsplit and subset in dplyr and mutate

metadata <- pData(gset)|>
    select(geo_accession,title,characteristics_ch1) |>
    filter(grepl("microRNA",title)) |>
    mutate(group=case_when(grepl("normal",characteristics_ch1)~"control",
                           grepl("tumor",characteristics_ch1)~"treatment"),
           sample = stringr::str_split(title,"_") %>% map_chr(., 1))

https://stackoverflow.com/questions/42565539/using-strsplit-and-subset-in-dplyr-and-mutate

R语言根据一列分组选择另一列最大的行


  # 创建示例数据
  data <- data.frame(
    group = c("A", "A", "B", "B", "C", "C"),
    value = c(10, 15, 8, 12, 5, 9)
  )
  
  # 根据group列分组，选择value列中最大的行
  data %>%
    group_by(group) %>%
    top_n(1, value)