Forum Discussion
Generating a list of months problem
I need to generate a list of dates having:
- [start_date]
- [number_of_months]
I tested that this works fine:
List.Transform({0..[number_of_months]-1}, each Date.AddMonths(DateFrom("2017-05-05"), _))And this works fine:
Date.AddMonths([invoices_start],_)
However this does not work:
List.Transform({0..[number_of_months]-1}, each Date.AddMonths([invoices_start],_))I get the message:
Expression.Error: We cannot apply field access to the type Number.
What's the problem??? It's driving me crazy.
Out of my head (so not tested), I'm pretty sure this should work:
List.Transform({0..[number_of_months]-1}, (x) => Date.AddMonths([invoices_start],x))By using (x) => instead of each, you can refer to the list item (i.e. the number) within the Date.AddMonths function.
3 Replies
Out of my head (so not tested), I'm pretty sure this should work:
List.Transform({0..[number_of_months]-1}, (x) => Date.AddMonths([invoices_start],x))By using (x) => instead of each, you can refer to the list item (i.e. the number) within the Date.AddMonths function.
It works! Thanks!
I have not seen (x) => f(x) in Power Query M Reference on MSDN, but probably I did not dig deep enough :-/
I still do not understand why solution with "each" works when I am increasing a constant date and does not work with the use of another field to deliver the date to be incremented.
Hi,
Can you try casting _ as number
something like this - List.Transform({1, 2}, each Date.AddMonths(Date.From("10/02/2017"), _ as number))P
