q - Composing symbols in KDB -


i'm working on python project interacting kdb+ database. future version of database have minor change, , since can't proceed python programming, thought i'd give shot myself instead of waiting update kdb developer.

i'm working mock database spits out randomly generated symbols this: instr1,instr2, instr81 etc.

i have looked around , beleive symbols generated line .gen.uni:$"instr",/: string til .gen.cfg.unisize;

the thing i'd achieve symbols exchangex.instry instead of instry (where x , y generated numbers).

for convieniece i've changed line $"instr",/: string til 4 brain doesn't hurt much.

how 1 achieve this? found out sv function i've tried many variations of sv ($"exchange",/: string til 4;$"instr",/: string til 4) nothing seems work.

thanks time!

ps: i've removed backticks here , there because of so's formatting

using roll operator useful generating kind of data: http://code.kx.com/q/ref/random/#roll

function below generate random list of symbols.

paramaters:

x - number of symbols want generated

y - number of different exchanges

z - number of different instruments

q){` sv' flip `$("exch",/:string x?y;"inst",/:string x?z)}   q){` sv' flip `$("exch",/:string x?y;"inst",/:string x?z)}[100;4;10] `exch0.inst2`exch3.inst3`exch3.inst0`exch2.inst0`exch3.inst4`exch3.inst4`exch2.inst0`exch0.inst3`exch3.inst4`exch0.inst5`exch3.inst0`exch1.inst5`exch1.inst7`exch2.inst4`exch2.inst3`exch3.inst1`exch3.inst6`exch2.inst2`exch2.inst.. q)

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