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Victor_Wong

Does anyone know why the first version of the following code fails while the second version succeeds?Thanks in advance,Victorq)cor . (0 0 0 1 2 3 4;5 6 7 8 9 0 3)' [0] cor . (0 0 0 1 2 3 4;5 6 7 8 9 0 3) ^q){cor[x;y]} . (0 0 0 1 2 3 4;5 6 7 8 9 0 3)-...

Victor_Wong

Hi,I have been using this piece of code I found on this group (https://groups.google.com/d/msg/personal-kdbplus/6-b8MaAO3fY/8Wq1pUjSbPkJ) with much success on v3.3 but found that it no longer works when I upgrade to v3.5. Specifically, the conn funct...

Victor_Wong

Hi,I am working with an API that is callback based (think alternating sets of request and requestCompleted messages) and in an attempt to avoid writing an ugly and difficult-to-maintain chain of nested callbacks, I am looking for a way to convert tho...

Victor_Wong

Hi,I am wondering why multi-threaded decompression (using peach) appears to be slower than using a single thread. Is there some sort of IPC between threads that's causing extra overhead? What is the right way to decompress in parallel?Thanks in advan...

Victor_Wong

In the Q for Mortals section on contexts (http://code.kx.com/wiki/JB:QforMortals2/workspace_organization#Contexts), it shows that one is able to retrieve variables from the default context by accessing the context dictionary: q)\d .newq.new)`.[`ztop]...

Victor_Wong

Gotcha.  Thank you.Much appreciated,Victor

Victor_Wong

Thank you for the suggestion.  It works perfectly in v3.5 now.

Victor_Wong

Here's a snippet of the nested callbacks I am referring to:coords:(101 205;120 673;...); i:0; sensors:(); readings:();{(neg h) `searchSensors x} each coords;sensorResults:{i+:1; $[i < count coords; sensors,:x; [i::0; sensorResults::{i+:1; $[i < count...

Victor_Wong

Thanks, Charles. So if I understand you correctly, it uses multiple threads when the query spans multiple partitions, or performs aggregations over partitioned or indexed columns, but does not differentiate between compressed and uncompressed columns...

Victor_Wong

I realize the motivation may not be clear from the example above, so I put together some use cases below. From testing, it looks like select doesn't do compressed column scans - for filtering or retrieval - in parallel, and one can outperform select ...

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cor

Sockets in v3.5

Converting callbacks to synchronous calls

Multi-threaded decompression

Assigning to variables in the default context

Re: cor

Re: Sockets in v3.5

Re: Converting callbacks to synchronous calls

Re: Multi-threaded decompression

Re: Multi-threaded decompression