通过模式匹配熔化柱子

时间:2018-04-15 05:44:57

标签: r dplyr tidyr tidyverse melt

我有一个非常广泛的数据框,其中包含标准的人口统计特征(年龄,性别,种族,教育,收入等)。我也有受访者对问题的回答,可以用四种方式之一(“cb”,“lb”,“lw”或“cw”)开头。

数据框目前采用宽格式,每行代表一个受访者的答案。我想将其转换为长格式,但我找不到使用reshape2库的直接解决方案。

我希望将所有人口统计特征保留为他们自己的列,但将问题,答案,信心和得分列减少到他们自己的熔化列中。这是我正在寻找的想法:

string <- "
response_id,age,sex,race_1,race_2,race_3,cb_1,cb_1_conf,cb_1_ans,cb_1_score,lb_1,lb_1_conf,lb_1_ans,lb_1_score
11,25,M,white,NA,NA,Astrophysicist,9,Dog,0,Jackson,8,Jackson,1
22,27,F,NA,black,asian,Monkey,8,Dog,0,Jackson,7,Jackson,1"

x <- read.csv(con <- textConnection(string), header=TRUE)

看起来像这样:

> x
  response_id age sex race_1 race_2 race_3           cb_1 cb_1_conf cb_1_ans cb_1_score    lb_1 lb_1_conf lb_1_ans lb_1_score
1          11  25   M  white   <NA>     NA Astrophysicist         9      Dog          0 Jackson         8  Jackson          1
2          22  27   F   <NA>  black     NA         Monkey         8      Dog          0 Jackson         7  Jackson          1

希望将其转换为此格式:

string_2 <- "
response_id,age,sex,race,question,response,confidence,correct_answer,score
11,25,M,white,cb_1,Astrophysicist,9,Dog,0
11,25,M,white,lb_1,Jackson,8,Jackson,1
22,27,F,black/asian,cb_1,Monkey,8,Dog,0
22,27,F,black/asian,lb_1,Jackson,8,Jackson,1
"

x_2 <- read.csv(con <- textConnection(string_2), header=TRUE)

  response_id age sex        race question       response confidence correct_answer score
1          11  25   M       white     cb_1 Astrophysicist          9            Dog     0
2          11  25   M       white     lb_1        Jackson          8        Jackson     1
3          22  27   F black/asian     cb_1         Monkey          8            Dog     0
4          22  27   F black/asian     lb_1        Jackson          8        Jackson     1

我尝试将df子集化为仅包含以cb,lb,cw或lw为前缀的列,然后是:

    melt(subset, id=c("ResponseID"), 
    +      measure.vars=grep("^(CB|LB|LW|CW)", colnames(subset)))

But this doesn't allow me to flexibly melt the _conf columns the _ans columns and the _score columns.  

I had to modify Maurits' answer a bit to work better for my case.  Here is my solution:

df_test <- df_ans %>%
    unite(race, contains("race"), sep = "/") %>%                # combine race_1,2,3
    mutate(race = str_replace_all(race, "(/NA|NA/)", "")) %>%   # replace NA from race
    select_all( ~ gsub("(^[A-Z][A-Z]_\\d+$)", "\\1_response", .)) %>%  # add "_response" to Q
    gather(key, val, -(1:24)) %>%                                # wide to long
    separate(key, c("q1", "q2", "item")) %>%                    # split into Q + item
    unite(question, q1, q2, sep = "_") %>%                      # [continued]
    mutate(item = gsub("_", "", item)) %>%                      # [continued]
    spread(item, val) %>%                                       # long to wide
    rename(answer = ans, confidence = con)                      # rename columns

1 个答案:

答案 0 :(得分:4)

以下是tidyverse解决方案:

x %>%
    unite(race, contains("race"), sep = "/") %>%                # combine race_1,2,3
    mutate(race = str_replace_all(race, "(/NA|NA/)", "")) %>%   # replace NA from race
    select_all( ~ gsub("^(\\w+_\\d)$", "\\1_response", .)) %>%  # add "_response" to Q
    gather(key, val, -(1:4)) %>%                                # wide to long
    separate(key, c("q1", "q2", "item")) %>%                    # split into Q + item
    unite(question, q1, q2, sep = "_") %>%                      # [continued]
    mutate(item = gsub("_", "", item)) %>%                      # [continued]
    spread(item, val) %>%                                       # long to wide
    rename(answer = ans, confidence = conf)                     # rename columns
#  response_id age sex        race question  answer confidence       response
#1          11  25   M       white     cb_1     Dog          9 Astrophysicist
#2          11  25   M       white     lb_1 Jackson          8        Jackson
#3          22  27   F black/asian     cb_1     Dog          8         Monkey
#4          22  27   F black/asian     lb_1 Jackson          7        Jackson
#  score
#1     0
#2     1
#3     0
#4     1

说明:

  1. 根据unite race_2 race race_3 race_1, NA的条目创建, d , whilst removing
  2. 剩下的就是gatherspreadseparate条目将questionanswer,{confidence分开{1}}和response
  3. 我在此假设所有问题的格式均为\\w+_\\d(例如cb_1lb_1);必要时进行调整。