[R] extract week from date

[Pingping Zheng]

Juan Ramon Gonzalez wrote:

>Hello R-users,
>
>Does anyone know how obtain the week of a date?  
>(in SPPS the instruction is "xdate.week")
>
>Thanks,
>
>Juan Ramon
>
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weekday<-format(x, "%w")
will change the date x into week as decimal number (0-6, Sunday is 0), or
week<-format(x, "%U%)
week of the year as decimal number (00-53) using the first Sunday as day 
1 of week 1, or
week<-format(x, "%W")
week of the year as decimal number (00-53) using the first Monday as day 
1 of week 1.

See help.start("strptime").

Pingping Zheng

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