linux - Need to get the dates of all mondays in a year

Question

I need to sort data on a weekly base and all i have are dates in a logfile. Therefore to sort out data per week i would like to create a list with the dates of all mondays for a given year. I have tried to work something out and the only idea i currently have is to use ncal with year and month as argument looping over all months and extracting all mondays. Isn't there a more efficient way?

Answer 1

To get all mondays, by getting all dates and filtering by Mondays:

for i in `seq 0 365`
    do date -d "+$i day"
done | grep Mon

Of course, you could also take a monday and keep incrementing by 7 days.