Copying Row values to other Column

[#1]

Hello,

Kindly help me I'm stuck when putting a formula into other column.

Here is expected output if SerialNumber is not empty copy row to Column ChipID else copy the same SN.

dtraw << New Column("ChipID", Character, Formula(
For( i = 1, i <= N Rows(dtraw), i++,
	If( Is Missing( :SerialNumber),
		:ChipID[i] = (:SerialNumber[1] & i = 1),
		:SerialNumber
		)
	)
);

[#2]

You can use Lag() function here.

Names Default To Here(1);

dt = New Table("Untitled 6",
	Add Rows(6),
	New Column("SerialNumber", Character, "Nominal", Set Values({"30_A0_0", "", "", "30_A0_01", "", ""}))
);
dt << New Column("ChipID", Character, Nominal, Formula(If(Is Missing(:SerialNumber), Lag(:ChipID), :SerialNumber)));

[#3 · Accepted solution]

Here is my way of handling the issue

dtraw << New Column( "ChipID",
	Character,
	Formula(
		If( :SerialNumber != "",
			hold = :SerialNumber
		);
		hold;
	)
);