Question

我想找到每月和每年电池运行分钟的总和。为此，我有以下条件：

如果Battery.voltage＆lt; 50然后＆＃34;是的，否则＆＃34;否。

注意：为了计算分钟的总和，我们可以在时间戳列中显示日，月，年，小时，分钟。

这是我的数据：

#          Time.stamp Battery.voltage Condition
# 1  01/04/2016 00:00              51        No
# 2  01/04/2016 00:01              52        No
# 3  01/04/2016 00:02              45       Yes
# 4  01/04/2016 00:03              48       Yes
# 5  01/04/2016 00:04              49       Yes
# 6  01/04/2016 00:05              55        No
# 7  01/04/2016 00:06              54        No
# ...

structure(list(
  Time.stamp = structure(c(1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L, 10L, 10L, 11L, 12L, 12L, 13L), 
                         .Label = c("01/04/2016 00:00", "01/04/2016 00:01", "01/04/2016 00:02", "01/04/2016 00:03", 
                                    "01/04/2016 00:04", "01/04/2016 00:05", "01/04/2016 00:06", "01/04/2016 00:07", 
                                    "01/04/2016 00:08", "01/04/2016 00:09", "01/04/2016 00:11", "01/04/2016 00:12", 
                                    "01/04/2016 00:13"), class = "factor"), 
  Battery.voltage = c(51L, 52L, 45L, 48L, 49L, 55L, 54L, 52L, 51L, 49L, 48L, 47L, 45L, 50L, 51L), 
  Condition = structure(c(1L, 1L, 2L, 2L, 2L, 1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 1L, 1L), 
                        .Label = c("No", "Yes"), class = "factor")), 
  .Names = c("Time.stamp", "Battery.voltage", "Condition"), 
  class = "data.frame", row.names = c(NA, -15L))

我的预期输出是这样的：

Month    year    Sum of mins running in battery
Jan      2016     350min
Feb      2016     450min
etc.

Answer 1

很遗憾，您的示例数据不能很好地代表您的问题陈述，因为它只包含一天的数据。提供一些为足够的条目（即日期）生成随机数据的代码将是有益的。

除此之外，您可以调整以下解决方案（此处我假设您的时间戳格式为"DD/MM/YYYY"）：

df %>%
    mutate(
        Time.stamp = as.POSIXct(Time.stamp, format = "%d/%m/%Y %H:%M"),
        byday = format(Time.stamp, "%d/%m/%Y"),
        bymonth = format(Time.stamp, "%d/%m"),
        byyear = format(Time.stamp, "%Y")) %>%
    group_by(byday) %>%
    summarise(sum.running.in.mins = sum(Condition == "Yes"))
## A tibble: 1 x 2
#  byday      sum.running.in.mins
#  <chr>                    <int>
#1 01/04/2016                   7

我们在此处创建列byday，bymonth和byyear，您可以根据这些列对条目进行分组并计算每个组的总运行时间总和。在上面的例子中，我按天计算总运行时间;为了获得每月的总运行时间，您可以将group_by(byday)替换为group_by(bymonth)。

使用相同的日期字段列计算日期差异

1 个答案: