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Kdb qstudio line plot

I have a table of the form

Timestamp, Symbol, Vol

and I would like to plot the aggregate daily volume per symbol in a line chart

select sum(Vol) by `date$Timestamp from Trades

gives me the plot for the daily volume. How can I get a line per symbol?

select sum(Vol) by `date$Timestamp, Symbol from Trades

Gives me two lines, one for Vol and one constant line for the max in symbols( symbols are int values)

And as a side question... How can I tell the plot to exclude missing dates in the time series or at least have values of 0 for those dates?

Solution

  • If you want to multi-graph then each line to draw needs to be a separate column of our output table. Which means you'd need to pivot your results table: https://code.kx.com/q/cookbook/pivoting-tables/

    For example, something like this:

    {P:exec distinct sym from x;exec P#(sym!size) by minute:minute from x}select sum size by sym,time.minute from lseTradeRT where sym in `AHT.L`BARC.L`BP.L`VOD.L

    but in your case replace the time.minute with `date$Timestamp. You should also filter on only a handful of syms or else the graph is unmanageable.