KX Technology
Using kdb+/q or any KX development tools? Discuss with our community of users and experts here!
cancel
Showing results for 
Search instead for 
Did you mean: 

Forum Posts

K question...

Content-Disposition: inlineHello,I'm trying to understand Arthur's famous two-liner Sudoku solver.I'm still in the first expression:p,:3/:_(p:9\:!81)%3What does 3/: and 9\: does? According to what I know the form of each-left and each right is:x f /:...

q installation problem

Installed q under Windows Vista but could not get itstarted. I get the following message: Microsoft Windows [Version6.0.6001]Copyright (c) 2006 MicrosoftCorporation. All rights reserved. C:\Users\orpap>cd\q C:\q>cd windows\w32 C:\q\windows\w32>qKDB+...

orpap by New Contributor
  • 413 Views
  • 3 replies
  • 0 kudos

Update symbols and tables in place ?

Hi,I want to save a table as splayed, now I have 2 ways:q) t:([] a:`a`b`c; b:1 2 3)q) syms:`symbol$()q) t:update a:`syms?a from tandq) t:([] a:`a`b`c; b:1 2 3)q) syms:distinct t.aq) update a:`syms$a from `tbut the following one failed:q) t:([] a:`a`b...

by Not applicable
  • 131 Views
  • 0 replies
  • 0 kudos

SQL Subset?

Hello,I tried this:q)trade:([]time:();sym:();price:();size:())q)`trade insert(09:30:00;`a;10.75;100),0q)tradetime sym price size-----------------------09:30:00 a 10.75 100q)s) insert into trade values (10:00:00,`b,22.34,120)k){j::3;t:r 2;f:$["("~r j;...

Q for Mortals 2

Last week this url was not requiring authentication:https://code.kx.com/trac/wiki/QforMortals2/contentsNow, apparently it does, any ideas why?Was it only open by oversight?

JB2 by New Contributor
  • 450 Views
  • 3 replies
  • 0 kudos

Where is the tick.zip?

I downloaded the kdb+ 32bit developer edition. Where is the tick.zippackage mentioned in the kdb+/tick documentation?

Hehe by New Contributor
  • 746 Views
  • 6 replies
  • 0 kudos

Keyed table and Joins ...

I am trying to load fixed width data from files into tables and jointwo such tables.I have successfully loaded the fixed width data. It seems I need tounderstand the following before I make further progress:1- Do the PK cols always need to be in the ...

Sudhan by New Contributor
  • 235 Views
  • 1 replies
  • 0 kudos

web actions and messages

How does one define webactions or dispatchers for the kdb server?Additionally, how does one define a message handler for processcommunication?Thanks.

jksmith by New Contributor
  • 243 Views
  • 1 replies
  • 0 kudos

directory globbing

is it possible to glob a directory of csv files for importing into kx?Possibly merging the tables into one?

doubling is an interesting theory (see url below) but...

in Dennis Shasha's primer at chapter 9 we read:...This section assumes you have some some familiarity...I assume one some would be more handsome...:)...The promised link:http://adsabs.harvard.edu/abs/2006AIPC..839..236GFor those of you who can read f...

Paul1 by New Contributor
  • 143 Views
  • 0 replies
  • 0 kudos

A small typo from evolution of an empty representation

Going through Dennis Shasha's primer, in chapter 6 where thedifference function is defined, we can read:difference[c;d] /returns 0#` because there is no such elementBut according to my downloaded free version it is now:difference[c;d] /returns `symbo...

Paul1 by New Contributor
  • 240 Views
  • 1 replies
  • 0 kudos

Sql Server to KDB

Hi... I was wondering what the best would be to copy a sql serverdatabase to kdb+ one. I saw in the code.kx that there is a odbc.kfile but I dont seem to have that with evaluation edition.

Sliding window

Mime-Version: 1.0 (Apple Message framework v919.2)Subject: Sliding windowDate: Wed, 9 Apr 2008 12:48:47 +0100X-Mailer: Apple Mail (2.919.2)How do you implement a sliding window?Assume that you need to take a movingaverage over the last 10 quotes. You...

joelr1 by New Contributor
  • 242 Views
  • 1 replies
  • 0 kudos

Limitations On Non-Commercial Version

I'd like to confirm the limitations of the non-commercial version onwindows.>From what I can see: 1. There's no slaves 2. Work space size is limited to 2GigI've tried starting like this: q.exe -s4 -w4096But this seems to make no difference. For a sta...

different contexts for remote execution

Mime-Version: 1.0 (Apple Message framework v919.2)Subject: different contexts for remote executionDate: Mon, 7 Apr 2008 23:53:18 +0100X-Mailer: Apple Mail (2.919.2)assuming that h was a handleto a remote q, it seems thath (get;var) and h "var"execute...

joelr1 by New Contributor
  • 352 Views
  • 2 replies
  • 0 kudos

q vector math not much faster than serial erlang code?

Mime-Version: 1.0 (Apple Message framework v919.2)Subject: q vector math not much faster than serial erlang code?Date: Mon, 7 Apr 2008 11:33:59 +0100Cc: Zvi Avraham X-Mailer: Apple Mail (2.919.2)http://groups.google.com/group/erlang-questions/browse_...

joelr1 by New Contributor
  • 535 Views
  • 4 replies
  • 0 kudos

The perils of benchmarking

Mime-Version: 1.0 (Apple Message framework v919.2)Subject: The perils of benchmarkingDate: Sun, 6 Apr 2008 15:38:18 +0100X-Mailer: Apple Mail (2.919.2)Suppose we had a list of 10000000phone numbers and wanted to takejust the first 8 digits of each.We...

joelr1 by New Contributor
  • 426 Views
  • 3 replies
  • 0 kudos

Q development tools in Eclipse

hi,is there a limitation in KDB+ 2.4 2008.03.31 for socket connections?I am trying to set up an Eclipse debug config as described here:http://www.qkdt.org/gettingstarted.htmland getting :"could not connect to Q at localhost:1444"connection refusedwha...

sparse arrays

Mime-Version: 1.0 (Apple Message framework v919.2)Subject: sparse arraysDate: Sun, 6 Apr 2008 00:04:15 +0100X-Mailer: Apple Mail (2.919.2)What is the most efficient wayto implement sparse arrays in q? Thanks, Joel--wagerlabs.com

joelr1 by New Contributor
  • 869 Views
  • 8 replies
  • 0 kudos

bring the slaves back!

Subject: bring the slaves back!Date: Sat, 5 Apr 2008 23:54:51 +0100X-Mailer: Apple Mail (2.919.2)X-Google-Approved: simon.garland@gmail.com via web at 2008-04-06 04:49:38Multithreading is absent on Mac OSX and notas powerful as it could be otherwise ...

joelr1 by New Contributor
  • 434 Views
  • 3 replies
  • 0 kudos

Welcome!

As members of this group you probably already know that we havereleased a free version of 32-bit kdb+, for all platforms, for non-commercial use. To learn kdb+ you will find a couple of other newdevelopments to be useful:- code.kx has been opened to ...