沿 csv 中的行计算 R 中的岛屿

Question

我之前问过这个问题，Frank 回答了。原题：

I would like to count islands along rows in a .csv. I say "islands" meaning consecutive non-blank entries on rows of the .csv. If there are three non-blank entries in a row, I would like that to be counted as 1 island. Anything less than three consecutive entries in a row counts as 1 "non-island". I would then like to write the output to a dataframe:

我稍微更改了输入 .csv，现在包含多个 islands/gaps，这样行就不仅仅是 "island" 行或 "non-island" 行。有人有什么建议吗？

输入.csv:

Name,,,,,,,,,,,,,
Michael,,,1,1,1,,,,1,,,,
Peter,,,,1,1,,,,,,,,,
John,,,,,1,,,,,,,,,
Erin,,,,,1,1,,,,1,1,,,

所需的数据帧输出：

Name,island,nonisland,
Michael,1,1,
Peter,0,1,
John,0,1,
Erin,0,2

Answer 1

将上一个问题的代码添加到稍作修改以获得 nonisland 列

# sample data
df <- read.csv(text="
,,,,,,,,,,,,,
Michael,,,1,1,1,,,,1,,,,
Peter,,,,1,1,,,,,,,,,
John,,,,,1,,,,,,,,,
Erin,,,,,1,1,,,,1,1,,,")

output <- stack(sapply(apply(df, 1, rle), 
            function(x) sum(x$lengths >= 3)))

output$nonisland <- sapply(apply(df, 1, rle), 
                      function(x) sum(x$lengths[!is.na(x$values)] < 3))

names(output) <- c("island", "names", "nonisland")

#  values   names nonisland
#1      1 Michael         1
#2      0   Peter         1
#3      0    John         1
#4      0    Erin         2

沿 csv 中的行计算 R 中的岛屿

counting islands in R along rows in csv

csv

r

gaps-and-islands