CODEWITHSUNDEEP
kdb+
MVP
MVP

Reputation: 25

How do I multiple two columns of data together in kdb/q?

I am trying to teach myself kdb/q programming. I can't seem to figure out how to take a simple table (columns symbol, price, and shares) and multiply price * shares to get volume. I've read Q for Mortals, code.kx.com, etc and am stuck. Could someone please give me a hint or point me in a direction of where I could figure out this simple problem! Thanks

Upvotes: 1

Views: 2060

Answers (2)

nyi
nyi

Reputation: 3229

checkout the q-sql for select/update queries.

Here is the update statement you are after: 

q)trade:([] symbol:5?`APPL`GOOG;  price:5?100.; shares:5?10)

q)update volume:price*shares from  trade
symbol price    shares volume
-------------------------------
APPL   21.09    6      126.54
APPL   88.22095 8      705.7676
APPL   25.0192  4      100.0768
GOOG   51.68842 1      51.68842
APPL   53.8142  8      430.5136

However, I'll recommend checking Q for mortals, it pretty much covers everything for Kdb+ beginner.

Upvotes: 3

C.Ross
C.Ross

Reputation: 251

Where t is the table name:

update volume: price*shares from t

Or

t: select symbol, price, shares, volume:price*shares from t

Upvotes: 7

Related Questions