Question

I have an irregular(?) time series data points in a day as following

Jun 5, 2012 10:58 AM
Jun 5, 2012 10:58 AM
Jun 5, 2012 11:59 AM
Jun 5, 2012 12:25 PM
Jun 5, 2012 1:07 PM
Jun 5, 2012 1:07 PM
Jun 5, 2012 1:17 PM
...

I would like to make a histogram where the x is the interval of hours from 0 hour to 23 and y is the count of the data points in each bin.

I was trying to do this in R and Excel by converting the data above into hour:minute format and then draw histograms.

Two challenges I faced:

1. How do I convert the data such as above into the standard time format where applications such as Excel or R can handle? is there such functions in each program?
2. How do you make histogram with such transformed data?

I tried using zoo packages, as.POSITlt functions, but I am lost.

Answer 1

have at look at the chron and lubridate packages

Time <- c("Jun 5, 2012 10:58 AM",
"Jun 5, 2012 10:58 AM",
"Jun 5, 2012 11:59 AM",
"Jun 5, 2012 12:25 PM",
"Jun 5, 2012 1:07 PM",
"Jun 5, 2012 1:07 PM",
"Jun 5, 2012 1:17 PM")
library(chron)
Time2 <- as.chron(Time, format = "%b %d, %Y %I:%M %p")
library(lubridate)
x <- hours(Time2) + minutes(Time2) / 60
hist(x)