ischumacher

import java.awt.Color
import java.awt.RenderingHints
import java.awt.image.BufferedImage
import java.io.File
import java.nio.file.Paths
import javax.imageio.ImageIO

fun proc(vararg cmd: String): Process {
	val pb = ProcessBuilder(cmd.asList())
	pb.redirectError(ProcessBuilder.Redirect.INHERIT)

ischumacher

//  Maps base 256 to base 85
val encoder = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ.-:+=^!/*?&<>()[]{}@%$#"
		.toCharArray()
//  Maps base 85 to base 256
//  We chop off lower 32 and higher 128 ranges
val decoder = byteArrayOf(
		0x00, 0x44, 0x00, 0x54, 0x53, 0x52, 0x48, 0x00,
		0x4B, 0x4C, 0x46, 0x41, 0x00, 0x3F, 0x3E, 0x45,
		0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
		0x08, 0x09, 0x40, 0x00, 0x49, 0x42, 0x4A, 0x47,

ischumacher

package ian.json

fun exampleJSONUsage() {
	var json = JSON.parseJSON("{a:5, b:'test', c: {d: 'xxxxxx', e: ['Hello','There','test','one']}}")
	// pretty printed JSON
	println(json)
	// Should be same as previous
	println(JSON.parseJSON(json.toString()))
	// get a child JSON object
	println(json.getJSONObject("c"))

ischumacher

(* Simulate tables *)
a = Table[{x, RandomReal[]}, {x, 1, 100, 2}];
b = Table[{x, RandomReal[]}, {x, 1, 100, 3}];

RJoin[a_, b_] := Block[{f},
  Do[
    f[x[[1]]] = x[[2]],
    {x, a}
    ];
   Cases[b /. {x_, y_} -> {x, y, f[x]}, {_, _, _Real}]

ischumacher

(*
Total possible number of items - n
Population size for collision probability - x

For 32 bit hash, collision prob = 0.5 when number of hashes is 77,162 
For 64 bit hash, collision prob = 0.5 when number of hashes is 5 billion.

Solve[CollisionProb[x, n] == 0.5, {x, n}]

n -> 0.721348 x^2

ischumacher

DateListPlot[
 Drop[Import["http://research.stlouisfed.org/fred2/data/OILPRICE.txt",
    "Table", "HeaderLines" -> 12, 
   "DateStringFormat" -> {"Year", "Month", "Day"}], 5], 
 Joined -> True, PlotRange -> All]