How to extract an interval of "hour:minute" type

Here is one way:
x <- read.table(text = "4352;2011-09-02 21:30:00;3242;
+ 4352;2011-09-02 21:31:00;3315;
+ 4352;2011-09-02 21:32:00;4241;
+ 4352;2011-09-02 21:33:00;5394;", sep = ';', as.is = TRUE)
# create a 'character' of just the time.  If the data is of
# the format above, 'substring' can be used
x$time <- substring(x$V2, 12, 16)
subset(x, time >= '21:31' & time <= '21:32')
V1                  V2   V3 V4  time
2 4352 2011-09-02 21:31:00 3315 NA 21:31
3 4352 2011-09-02 21:32:00 4241 NA 21:32

Hi,

I 'd like to know how to extract an interval of "hour:minute" type from a
column of POSIXlt POSIXct type.
For instance:

my_data.csv:

4352;2011-09-02 21:30:00;3242;
4352;2011-09-02 21:31:00;3315;
4352;2011-09-02 21:32:00;4241;
4352;2011-09-02 21:33:00;5394;
...
4352;2011-09-02 01:02:00;67;
4352;2011-09-02 01:03:00;67;
4352;2011-09-02 01:04:00;67;
....

I loaded my_data.csv into a data.frame.

I 'd like to select rows where times T satisfies 21:30:00<= T <=22:30:00. I
do not worry about the date. I just need ?the time to select the interval

Thanks for your help

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How to extract an interval of "hour:minute" type

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