I have a table and a function:
table:([] id:til 5; name:("one";"two";"three";"four";"five"))
fu:{[x] x,"_",x}
And I want to apply the function in an update statement on each row and set the result into a new column 'xyz'. How can I do that? This here does not work, as it seems to evaluate the argument as a list:
xyz:update x:fu[name] from table
You need to use the each-both operator to ensure the function runs on each row separately:
q)update xyz:fu'[name] from table
id xyz
----------------
0 "one_one"
1 "two_two"
2 "three_three"
3 "four_four"
4 "five_five"
Use each-both: https://code.kx.com/q/ref/adverbs/#each-both
q)update xyz:fu'[name]from table
id name
----------------
0 "one_one"
1 "two_two"
2 "three_three"
3 "four_four"
4 "five_five"
