Convert a temporary string to a temporary or numeric format

Question

I have a time column in the format 00:00 00:30 01:00.

I want a subset at certain hours, but I don’t understand how to convert it to the correct format
for the date I used as.date (), is there something similar?

Answer 1

I'm sorry that I received it, I used the strptime and strftime functions, for example:

strftime (strptime (x, format = "% H:% M"), "% H")