group_by选择前两行，然后spread() [英] group_by to select first two rows, then spread()

问题描述

我正在尝试重新格式化，以便可以生成 On Hold Begins 的所有实例以及紧随其后的下一个事件的数据框. On Hold Begins 是开始事件，我想捕获其 Timestamp 和 Deviation 以及 Timestamp 和 Deviation (紧随其后的下一个事件)(例如，低于阈值，已启用阶段).

I'm trying to reformat this so I can generate a dataframe of all instances of On Hold Begins and the next event immediately after it. On Hold Begins is the start an event, and I'd like to capture its Timestamp and Deviation as well as the Timestamp and Deviation for the next event immediately after it (i.e. Below Thresold, Stage Enabled).

如果可能的话，我只想将具有 On Hold Begins 作为第一个事件的切片包括在内(因此理想的解决方案将不包括上面的第1和2行)，不希望额外的X列，并希望将其格式化为我所描述的格式.这类似于:

If possible, I only want to include slices that have On Hold Begins as the first event (so the ideal solution would not include rows 1 &2 above), do not want the additional X columns, and would want it to be formatted as I described. This is similar to: How can I spread repeated measures of multiple variables into wide format?, but I ran into errors asking for a dictionary when I tried it.

非常感谢您的帮助.

推荐答案

使用基本R的简单解决方案:

Simple solution using base R:

first_idx <- which(df$Flag == "On Hold Begins")
second_idx <- first_idx + 1
df_1 <- df[first_idx,]; colnames(df_1) <- paste("Flag 1 ", colnames(df_1))
df_2 <- df[second_idx,]; colnames(df_2) <- paste("Flag 2 ", colnames(df_2))
cbind(df_1, df_2)

   Flag 1  Stage   Flag 1  Flag Flag 1  Timestamp Flag 1  x Flag 1  Deviation Flag 2  Stage    Flag 2  Flag Flag 2  Timestamp Flag 2  x Flag 2  Deviation
3              a On Hold Begins     4/29/17 15:34         1             1.200             a Below Threshold     4/29/17 15:35         1            0.0000
6              a On Hold Begins     4/29/17 21:49         5             1.200             a Below Threshold     4/29/17 21:50         5            0.0000
10             a On Hold Begins     4/29/17 23:29         6             1.200             a Below Threshold     4/29/17 23:30         6            0.0000
12             a On Hold Begins     5/16/17 17:22         8             1.774             a   Stage Enabled     5/16/17 17:39         8            1.8973
15             a On Hold Begins     5/16/17 19:14         9             1.095             a Below Threshold     5/16/17 19:15         9           -0.2252
21             b On Hold Begins     4/28/17 22:05       125             1.200             b    On Hold Ends     4/28/17 22:07       125            1.2000
24             b On Hold Begins     4/28/17 23:29       128             1.200             b Below Threshold     4/28/17 23:30       128            0.0000
26             b On Hold Begins      4/29/17 1:53       133             1.200             b Below Threshold      4/29/17 1:55       133            0.0000
29             b On Hold Begins      4/29/17 2:40       135             1.200          <NA>            <NA>              <NA>        NA                NA

这篇关于group_by选择前两行，然后spread()的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！