arrayformula sum in Google spreadsheet

Question

How do you arrayformula() a sum() such as:

=sum(A1:H1)

I need to go down 1000 rows.

Answer 1

Using DSUM:

=ARRAYFORMULA(DSUM(
  TRANSPOSE(FILTER({A2:A,A2:H},A2:A<>"")),
  SEQUENCE(COUNTA(A2:A)),{IFERROR(1/0);IFERROR(1/0)}))

notes:

• {IFERROR(1/0);IFERROR(1/0)} is to make zero creteria for DSUM.

• {A2:A,A2:H} -- added fake column for DSUM to mimic header column.

• may be able to cahnge the formula into DMAX or DAVERAGE