Lars Rune Nøstdal lnostdal

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Clojure, PostgreSQL, Linux

Traveling freelancer, farmer and sailor.

lnostdal / placeholder.txt

Created March 16, 2019 21:53

aoeuaoeu

lnostdal / trend-1 XBTUSD 2h [bt-9 branch].txt

Last active March 11, 2019 21:29

trend-1 XBTUSD 2h [bt-9 branch]

687a0ac

lnostdal / trend-1 XBTUSD 15sec [bt-8 branch].txt

Created February 27, 2019 10:41

trend-1 XBTUSD 15sec [bt-8 branch]

8d69b3b

lnostdal / trend-1 XBTUSD 1min [bt-7 branch].txt

Last active February 27, 2019 06:17

trend-1 XBTUSD 1min [bt-7 branch]

b87b5ff -->

lnostdal / trend-1 XBTUSD 5min [bt-6 branch].txt

Last active February 26, 2019 13:04

trend-1 XBTUSD 5min [bt-6 branch]

37167d096394547c3fbbdb28e99ca3e4dec8fb2c -->

lnostdal / clj_bug.clj

Last active February 6, 2019 03:55

clojure compiler bug?

	;; maybe something related to locals clearing and/or forwarding of bindings (?)
	;; warning: this will lead to heap overflow quite fast!


	(let [s (range)]
	(if true
	(future
	(loop [s s]
	(recur (rest s))))
	:whatever))

lnostdal / lazy-seq + seque.clj

Last active January 19, 2019 05:27

Clojure for fast processing of streams of data via LAZY-SEQ and SEQUE

	;; www.Quanto.ga
	;;
	;; * You have a stream of data where generating each new element for the stream takes some time.
	;; * You consume and do some calculations on each element from the stream; this too takes some time.
	;; * When the consumer is done with its calculations for a element (or chunk of elements!) you do
	;; not want it to wait around for the code that fetches new elements to finish fetching a new element
	;; -- because this could be done in the background while you where doing the calculations.
	;;
	;; A way to deal with this is to use SEQUE which will keep production N steps in advance of consumption
	;; via a background thread that works on Clojue seqs.

lnostdal / async-consume-buffer.clj

Last active January 10, 2019 02:29

clojure.core.async: consume channel buffer without blocking

	;; www.Quanto.ga
	;;
	;; I've found this to be useful at times:

	(defn async-consume-buffer
	"Consume as many values from `ch` as possible without blocking.
	Once `ch` blocks (i.e. its buffer is empty), the values are returned as a vector."
	([ch]
	(async-consume-buffer ch false))

lnostdal / interactive_brokers_test.clj

Last active July 31, 2018 22:26

Interactive Brokers API test in Clojure

	(def %bnds (get-thread-bindings)) ;; TODO: Seems kind of hacky, but needed as sometimes (EWrapper/error Exception) is sourced from different threads(!).


	(deftype IB
	[^:unsynchronized-mutable ^int next-order-id
	^:unsynchronized-mutable ^com.ib.client.EClient eclient
	^:unsynchronized-mutable ^com.ib.client.EReaderSignal ereader-signal]


	com.ib.client.EWrapper

lnostdal / ma_array_vs_ma_transducer.clj

Last active August 20, 2018 02:24

Moving average in Clojure using JVM arrays vs. transducer variant

	;; ...and yes; I know there are more efficient ways to do this.


	(defn sma ^doubles [^doubles pseries ^long ma-len]
	"Simple Moving Average: https://en.wikipedia.org/wiki/Moving_average#Simple_moving_average

	Returns a JVM double[]. Head is padded with ##NaN entries to align it with `pseries`."
	(if (= ma-len 1)
	pseries
	(let [pseries-len (alength pseries), ret (double-array pseries-len ##NaN)]