eldritchideen

defmodule Stocks do

  def get_new_highs do
    HTTPoison.start
    resp = HTTPoison.get!("http://www.smh.com.au/business/markets/52-week-highs?page=-1",[], [proxy: "http://proxy.cat.com:80"])
    data = Floki.find(resp.body, "#content  section  table  tbody  tr  th  a")
    Enum.map(data, fn({_,_,[code]}) -> code end)
  end

end

eldritchideen

Sample Project

Starting from:

lein new foo
cd foo

Say I have a random JAR file that is not available in any repository:

touch README.md

eldritchideen

from zipline.algorithm import TradingAlgorithm
from zipline.transforms import MovingAverage
from zipline.utils.factory import load_from_yahoo
from zipline.finance.slippage import FixedSlippage
from zipline.finance.commission import PerShare
from datetime import datetime
import matplotlib.pyplot as plt

class DualMovingAverage(TradingAlgorithm):

eldritchideen

(defn average [coll]
  (/ (reduce + coll)
      (count coll)))

(defn ma [period coll] 
  (lazy-cat (repeat (dec period) nil) 
            (map average (partition period 1  coll))))

eldritchideen

(ns scratch.core
  (:require [clojure.core.async :as async :refer [go-loop <! chan <!! >! >!!]])
  (:gen-class))

(defn make-actor
  "Creates actor of specific name" [name]
  (let [in (chan 10)]
    (go-loop [[msg-type sender msg-body :as data] (<! in)]
             (when data
               (println (str "Actor " name " got message " msg-type

eldritchideen

import dxfgrabber

dxf = dxfgrabber.readfile('surface0.dxf')
all_surface_entities = [entity for entity in dxf.entities if entity.layer == '0']
all_progress_line_entities = [entity for entity in dxf.entities if entity.layer == 'Progress Line']

f = open('surface_points.csv', 'w')

# List of Point objects
for p in all_surface_entities:

eldritchideen

from pandas import *
import pandas.io.data as web
import datetime

start = datetime.datetime(2010, 1, 1)
end = datetime.datetime(2014, 8, 15)

# Get daily price data
ctx = web.DataReader('ctx.ax', 'yahoo', start, end)

eldritchideen

(ns scraping.core
  (:gen-class)
  (:import (org.jsoup Jsoup) 
  (org.jsoup.select Elements)
  (org.jsoup.nodes Element)))

(def URL "http://www.smh.com.au/business/markets/52-week-highs?page=-1")

(defn get-page []
  (.get (Jsoup/connect URL)))

eldritchideen

import org.jsoup.Jsoup
import org.jsoup.nodes.Element
import scala.collection.JavaConversions._

System.setProperty("http.proxyHost", "xxx.xxx.xxx")
val doc = Jsoup.connect("http://www.smh.com.au/business/markets/52-week-highs?page=-1").get()
//doc.body()
val elems = doc.select("#content > section > table > tbody > tr > th > a")

val foo = for ( e <-  elems) yield e.text

eldritchideen

This is my recommended path for learning Haskell.

Something to keep in mind: don't sweat the stuff you don't understand immediately. Just keep moving.

Primary course

http://www.seas.upenn.edu/~cis194/lectures.html Brent Yorgey's course is the best I've found so far and replaces both Yann Esposito's HF&H and the NICTA course. This course is particularly valuable as it will not only equip you to write Haskell but also help you understand parser combinators.

Exercises for practice