Power Query, subtraction between two lists

[peterhui50]

Hello, I have columns with lists.

Column [Numbers_1_3_5] has this.

Column [Numbers_2_4_6] has this 

I want to just make a new column that finds the difference between the two lists. 

I tried Value.Subtract([Numbers_1_2_5],[Numbers_2_4_6]) but this doesn't work because they are in list format.

I'm used to R being able to do this but how do I do this in Power BI?

The first one should be - 11 minus 18, 22 minus 28, 35 minus 37 = -7,-6,-2

Thanks

[peterhui50]

Thanks that's amazing. I was trying to create functions and such and this solves it.

[OwenAuger · Accepted solution]

Hi @peterhui50 

It's not quite as simple as in R I'm afraid, but you can use List.Zip to combine corresponding elements from a list of lists, then perform operations on the resulting list.

For your example, the code to enter in the calculated column dialog box would be something like this:

List.Transform( List.Zip( {[Numbers_1_3_5], [Numbers_2_4_6]} ), each _{1}-_{0})

 Regards,

Owen

[AlexisOlson]

You could also create a virtual table and add a custom column:

Table.AddColumn(
    Table.FromColumns({[Numbers_1_3_5], [Numbers_2_4_6]}, {"135", "246"}),
    "Diff", each [246] - [135]
)[Diff]

This returns the custom column from the virtual table.