Retrieve date from year-week

Hi all,

I’ve tried several possibilities, however without any luck. I would like to retrieve a given date based on its year-week number (both separate columns). Can somebody help me with this?

Thanks a lot!

year-week-to-date 1.knwf (4.8 KB)

Rergards, Tayfun

Welcome tot he forum @Tayfun.

I’ve tried several possibilities

Such as?

I would like to retrieve a given date

What does that mean exactly?
What should the output look like?

Thanks @elsamuel!

I would like to retrieve the first day of a specific week and year, like this:


See also my currently workflow.
Week-year to date.knwf (12.0 KB)

I have used the manipulation string : string((toInt(substr($column1$,0,2))-1)7+1)+“_”+substr($column1$,length($column1$)-4,4) based on a closed topic. They suggest to use: string(“1_”+$column1$) and date format=e_w_Y to get Monday as the first day, but I can’t get this right.

*link to topic: convert week/Year to date - #3 by ReWi

Thanks again!

I think you’re overcomplicating this by trying to copy and paste from that previous topic. Instead I would recommend trying to understand what each step does, then applying those concepts to your own workflow.

When I go through this process, I get this result:


Oh wow, indeed, I made it to complex. This is great! I understand it now - especially how the String to Date&Time node works. Thanks a lot!!

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Hi elsamuel,

I have one additional question.

After “String to Date&Time” I’ve included a cutoff to only get data until today. Then I added 12 additional rows. Basically, I need 12 data points in the future and only column “data” should be empty. The other columns (i.e., Year, week and date) must be extended.

I try to do this with “Create Date&Time range” node with a fixed rows (12x) and an interval of 1 week. The reason why i did this to take into account the year transition. However, I am stuck once again since I can’t joint this new table with the table above (no unique columns).

I first tried this with the “missing value” node in the above flow, but it doesn’t take into account a year transition.

Perhaps you can help me with this?


I think the Add Empty Rows node is unnecessary.

I’d use a Concatenate node to append the new rows (from the Extract Date&Time Fields node) to the main table.


Thanks elsamuel, that just worked like magic! In my personal workflow I needed to rename the columns of Extract Date&time similar to my main table first, then it worked just fine!

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