Part 2: Who’s Talking About the Future of Newspapers?

After breaking down the overall types of tweets from people, next step was to create scatter plots of their activity.

Unfortunately, Excel will only plot 250 data points – how unreasonable! Luckily I love breaking Excel and coding something that will do what I want it to do and look prettier, so voila.

Color scheme:

1. Is directed at someone by starting with an @
2. Contains a mention (@) of someone else
3. Contains a link

Otherwise, the point for that tweet is light gray. Note this is done in the order above, so if 1 is true, then it doesn’t matter if both 2 and 3 are true or false – the tweet will be pink. If 2 is true, the tweet may or may not contain a link – it will still be purple.

I used the Processing core.jar library within Eclipse, along with the data-structures I created originally and the Apache POI code for extracting the data from Excel.

I’m enclosing the code below, with some comments:

• This code will not compile even with the Processing core.jar library (requires data-structure code that I have not yet released).
• There is a horrible hack for calculating the time passed since original date – if you’re doing anything more with time consider Joda Time instead.
• The code is written to visualize this data and only this data. Whilst I may create a proper ScatterPlot class for Processing at some point, I’ll probably wait until Java 7 because without lambda functions it will require either a standard data format, or some kind of interface hack to create an adapter pattern. I don’t like either of these approaches.
• Aside from this, if you have some other use for it feel free to ping me with questions!

package com.catehuston.caitlin.viz;

import java.io.IOException;
import java.util.Calendar;
import java.util.Date;

import com.catehuston.caitlin.datastructures.Tweet;
import com.catehuston.caitlin.datastructures.User;
import com.catehuston.caitlin.parse.UserList;

import processing.core.PApplet;

@SuppressWarnings("serial")
public class Scatterplot extends PApplet {

	private static final int w = 1260; // 1160 for graph
	private static final int h = 600; // 480 for graph

	// spacing at either side
	private static final int xmargin = 70;
	private static final int ymargin = 60;

	// axis length
	private static final int xlen = w-(xmargin*2);
	private static final int ylen = h-(ymargin*2);

	// increments for day, hour, minute
	private static final int di = xlen/58;
	private static final int hi = ylen/24;
	private static final double mi = hi/60d;

	// user we're graphing
	private int index = 5;
	private User user;

	// calendar for date comparison
	Calendar startDate;

	public void setup() {
		UserList ul;
		try {
			// generate user list from spreadsheet
			ul = new UserList("../data/data_june16_top20.xls");
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
			return;
		}

		// get data just for the user we're interested in
		user = ul.get(index);

		// set applet size
		size(w, h);

		// draw() method will be called only once
		noLoop();

		// set up calendar with base date
		startDate = Calendar.getInstance();
		startDate.set(Calendar.YEAR, 2010);
		startDate.set(Calendar.MONTH, Calendar.FEBRUARY);
		startDate.set(Calendar.DAY_OF_MONTH, 1);
		startDate.set(Calendar.HOUR_OF_DAY, 0);
		startDate.set(Calendar.MINUTE, 0);
	}

	public void draw() {
		// set background color - dark grey
		background(64);

		// set foreground color for text and axes - light grey
		stroke(238);
		fill(238);

		// draw user name string top left
		text(user.getUser(), 5, 15);

		// draw x-axis
		int ypos = ylen+ymargin;
		line(xmargin, ypos, xmargin + xlen, ypos);
		// add major markers

		// initial
		line(xmargin, ypos, xmargin, ypos+5);
		text("Feb 1, 2010", xmargin, ypos+20);

		// mid-feb
		int inc = 13*di;
		line(xmargin + inc, ypos, xmargin + inc, ypos+5);
		text("Feb 14, 2010", xmargin + inc, ypos+20);

		// start of march
		inc = 28*di;
		line(xmargin + inc, ypos, xmargin + inc, ypos+5);
		text("Mar 1, 2010", xmargin + inc, ypos+20);

		// mid march
		inc = inc + 14*di;
		line(xmargin + inc, ypos, xmargin + inc, ypos+5);
		text("Mar 15, 2010", xmargin + inc, ypos+20);

		// end of march
		inc = 58*di;
		line(xmargin + inc, ypos, xmargin + inc, ypos+5);
		text("Mar 31, 2010", xmargin + inc - 60, ypos+20);

		// draw y-axis
		line(xmargin, ymargin, xmargin, ypos);
		// add markers
		for (int i = 0; i < 2401; i+=200) {
			inc = i/100*hi;
			ypos = ymargin + ylen - inc;
			line(xmargin-5, ypos, xmargin, ypos);
			String hrs = i + "h";
			if (i == 0) {
				hrs = "0000h";
			}
			else if (i < 1000) {
				hrs = "0" + hrs;
			}
			text(hrs, xmargin-50, ypos+10);
		}

		// go through and plot points, color according to type
		for (Tweet t : user.getTweets()) {
			// set color according to tweet type
			// @ message
			if (t.isDirected()) {
				// pink
				stroke(236, 0, 128);
				fill(236, 0, 128);
			}
			// someone else is mentioned
			else if (t.isMention()) {
				// purple
				stroke(140, 9, 214);
				fill(140, 9, 214);
			}
			// contains link
			else if (t.hasLink()){
				// yellow
				stroke(255, 126, 0);
				fill(255, 126, 0);
			}
			// otherwise
			else {
				stroke(238);
				fill(238);
			}

			Date d = t.getDate();
			int x = getXPos(d);
			int y = getYPos(d);
			ellipse(x, y, 3, 3);
		}
	}

	private int getXPos(Date date) {
		// make calendar with specified date
		Calendar newDate = Calendar.getInstance();
		newDate.setTime(date);

		// count how many days we go back to find start date
		int count = -1;
		while(startDate.before(newDate)) {
			count++;
			newDate.add(Calendar.DATE, -1);
		}

		return xmargin + count * di;
	}

	private int getYPos(Date date) {
		// put date in calendar so we can manipulate it
		Calendar time = Calendar.getInstance();
		time.setTime(date);

		// work out hour increment
		int hrs = time.get(Calendar.HOUR_OF_DAY) * hi;
		// wor out minute increment
		double mins = time.get(Calendar.MINUTE) * mi;

		// return y value
		return (int) (ylen + ymargin - hrs - mins);
	}
}