Chris Essig

Walkthroughs, tips and tricks from a data journalist in eastern Iowa

Archive for the ‘coding’ Category

Leaflet formula: Counting markers within a radius (version 2)

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A couple of years ago, I open-sourced a project that allows you to count how many markers are within a circle using Leaflet. As part of the template, a user needs to enter an address to get a marker to show up on the map.

Two weeks ago, Jefferson Guerrón reached out to me because he was creating something similar that didn’t require a user to type in their address. He was using the plugin Leaflet.draw to get the marker on the map. But he was having a hard time getting a circle to show up around the marker and count the other markers within that circle.

After a few back-and-forth emails, we were able to come up with a solution. Here’s a look of the final project. And the code is available on Github.

If you have questions, don’t hesitate to e-mail or comment.

Written by csessig

December 14, 2016 at 5:15 pm

D3 formula: Splitting elements into columns

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icons_columnsD3 can be a tricky — but powerful — beast. A month ago, I put together my most complex D3 project to date, which helped explain Iowa’s new Medicaid system

One of the first places I started on this project was building a graph that will take an icon and divide it into buckets. I didn’t see any openly available code that replicated what I was trying to do, so I’d figure I’d post my code online for anyone to use/replicate/steal.

For this project, I put the icons into three columns. In each column, icons are placed side by side until we get four icons in a row, then another row is created. You can see this in action by clicking the button several times. And all of this can be adjusted in the code with the “row_length and “column_length” variables.

To move the icons, I overlaid three icons on top of each other. When the button is clicked, each of the icons gets sent to one of the columns. The icons shrink as they reach their column. After this transition is finished, three more icons are placed on the DOM. And then the whole process starts over.

A bunch of math is used to determine where exactly on the DOM each icon needs to go. Also, we have to keep track of how many icons are on the DOM already, so we can break the icons into new rows if need be.

Data is required to make D3 run so my data is a simple array of [0,1,2]. The array has three values because we have three columns on the page. We do some calculations on the values themselves and then use SVG’s transform attribute to properly place the icons on the DOM. We use D3’s transition function to make it appear like the icons are moving into the icons, not just being placed there.

Hopefully this helps others facing similar problems in D3. If you have any questions, just leave them in the comments.

Written by csessig

May 2, 2016 at 12:30 pm

Save your work because you never know when it will disappear

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We are a few weeks into the new year, but I wanted to look back at the biggest project I worked on in 2015: The redesign of KCRG.com.

While most of my blog posts are full of links, I can’t link to that site. Why? Because it’s gone.

What?

In a series of very unfortunate events, the site we spent many, many months planning and developing is already gone.

The timeline: We started preparing for the redesign, which was BADLY needed, in early 2015. We then built it over the course of several months. Finally, it was launched in July. Then, in a move that surprised every one, KCRG was bought by another company in September.

At the time, I was optimistic that the code could be ported over to their CMS. And the site wouldn’t die.

My optimism was short lived. Gray has a standard website template for all its news sites, and they wanted that template on KCRG.

So in December, the website we built disappeared for good.

 

The KCRG website you see now is the one used and maintained by Gray.

Obviously, this was a big shock for our team. Even worse, the code we wrote was proprietary and requires Newscycle Solutions to parse and display. So even if I wanted to put it on Github, it wouldn’t do anyone any good.

I’m not used to the impermanence of web. When I had my first reporting job in Galesburg, I saved all the newspapers where my stories appeared. And unless my parents’ house catches on fire, those newspapers will last for a long time. They are permanent.

Not so online. Websites disappear all the time. And those who build them have barely any record of their existence.

Projects like PastPages and the Wayback Machine keep screenshots of old websites, which is better than nothing. But their archives are far cries from the living, breathing websites we build. A screenshot can’t show you nifty Javascript.

It’s an eery feeling. What happens in five years? Ten years? Twenty years? Will any of our projects still be online? Even worse: Will technology have changed so much that these projects won’t even be capable of being viewed online? Will online even exist?

Think about websites from 1996. They are long gone. Hell, many sites from two years ago have vanished.

I don’t have good answers. Jacob Harris has mulled this topic and offered some good tips for making your projects last.

But it’s worth pondering when you’re done with projects. What can I do to save my work for the future? I have a directory of all of my projects from my Courier days on an external hard drive. I have an in-process directory for The Gazette as well.

I hold onto them like I did my old newspaper clippings. Although, I’m confident those clippings will last a lot longer than my web projects.

Written by csessig

January 21, 2016 at 11:52 am

New adventures

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Some exciting personal news: I’ll be joining the Cedar Rapids Gazette and KCRG as their Interactive News Developer at the end of the month. My last day at the Waterloo-Cedar Falls Courier is Friday.

The new job will let me develop full time, meaning I will be coding more than I have. And I will continue to work in a newsroom, which is awesome. Needless to say, I’m very excited about the move.

I spent the last three years The Courier, and as this blog shows, I learned a ton in that time span. I will greatly miss working there. And more importantly, I’ve very, very proud of all the awesome work we did while I was there.

Here’s to new adventures!

Written by csessig

May 15, 2014 at 2:37 pm

How laziness led me to produce news apps quicker

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Note: This is cross-posted from Lee’s data journalism blog, which you can read over there by clicking here.

ssAn important trait for programmers to adopt, especially for those who are writing code on deadline, is laziness. While that sounds counter-productive, it can be incredibly beneficial.

When writing code, you  do a lot of repetitive tasks. If you’re using a Javascript library for mapping, for instance, you’ll need to copy and paste the Javascript and CSS files into a new directory every time you start a new project. If you want to use plugins with that map, you will need to include their files in the directory as well.

The more complicated your project, the more libraries you will likely use, which means a lot of tedious work putting all those files in the new directory.

And that’s before you even start to code. If you want your projects to have a similar look to them (which we do at the Courier), you will need to create code that you can to replicate in the future. And then every time you want to use it, you will need to rewrite the same code or, at the very least, copy code from your old projects and paste it into your new project.

I did this for a long time. Whenever I was creating  a new app, I’d open a bunch of projects I’ve already completed, go into their CSS and JS files, copy some of it and paste it into the new files. It was maddening because I knew with every new project, I would waste hours basically replicating work I had already done.

This is where laziness pays off. If you are too lazy to do the same things over and over again, you’ll start coming up with solutions that automatically does these repetitive tasks.

That’s why many news apps teams have created templates for their applications. When they create new projects, they start with this template. This allows their apps to have a similar look. It also means they don’t have to do the same things over and over again every time they are working with a project.

App templating is something I’ve dabbled with before. But those attempts were minor. For the most part, I did a lot of the same mind-numbing tasks every time I wanted to create a map, for instance.

Fortunately I found a good solution a few months ago: Yeoman, which is dubbed “the web’s scaffolding tool for modern web apps,” has helped me eliminate much of that boring, repetitive work.

Yeoman is built in Node. Before I stumbled upon it a few months ago, I knew very little about Node. I still don’t know a ton but this video helped me grasp the basics. One advantage of Node is it allows you to run Javascript on the command line. Pretty cool.

Yeoman is built on three parts. The first is yo, which helps create new applications and all the files that go with it. It also uses Grunt, which I have come to love. Grunt is used for running tasks, like minifying code, starting a local server so you test your code, copy files into new directories and a whole bunch of other things that makes coding quicker, easier and less repetitive.

Finally, Yeoman uses Bower, which is a directory of all the useful packages you use with applications, from CSS frameworks to Javascript mapping libraries. With a combination of Bower and Grunt, you can download the files you need for your projects and put them in the appropriate directories using a Grunt task. Tasks are written in a Gruntfile and run on the command line. The packages you want to download from Bower and use in your project are stored in bower.json file.

In Yeoman, generators are created. A generator makes it easy to create new apps using a template that’s already been created. You can either create your own generator or use one of the 400+ community generators. The generators themselves are directories of files, like  images, JS files, CSS stylesheets, etc. The advantage of using generators is you can create a stylesheet, for instance, save it in the generator directory and use that same stylesheet with every new project you create. If you decide to edit it, those changes will be reflected in every new project.

When you use a generator, those files are copied into a new directory, along with Grunt tasks, which are great for when you are testing and deploying your apps. Yeoman also has a built-in prompt system that asks you a series of questions whenever you create an app. This helps copy over the appropriate files and code, depending on what you are trying to make.

I decided I would take a stab at creating a generator. The code is here, along with a lot more explanation on how to use it. Basically, I created it so it would be easier to produce simple apps. Whenever I create a new Leaflet map, for instance, I can run this and a sample map with sample data will be outputted into a new directory. I also have a few options depending on how I want to style the map. I also have options for different data types: GeoJSON, JSON with latitude and longitude coordinates and Tabletop. What files are scaffolded out depends on how you responded to the prompts that are displayed when you first fire up the generator.

There is also an option for non-maps. Finally, you can use Handlebars for templating your data, if that’s your thing.

My hope is to expand upon this generator and create more options in the future. But for now, this is easy way to avoid a bunch of repetitive tasks. And thus, laziness pays off.

If you are interested in creating your own generator, Yeoman has a great tutorial that you should check out.

Written by csessig

February 19, 2014 at 12:08 pm

How we used a Google spreadsheet to power our election app

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Election 2013 app screen shot

Last Tuesday was election night in the Cedar Valley. While we didn’t have a huge number of contested races on the ballot, we did have a mayor’s race in Waterloo and Waverly, Iowa, as well as city council races in several area towns.

As NPR’s Jeremy Bowers proudly proclaimed, election nights are exciting times for news nerds. This election, we decided to do a little bit of experimenting.

Before the election, we posted biographical information for all the candidates running in a contested race in Waterloo, Cedar Falls and Waverly. We also promoted other races in smaller towns. This gave our readers a good overview of the races on the ballot and information on the candidates. And best of all, it was all in one place.

Three reporters were responsible for getting the biographical information for each candidate and entering it online. We used a Google spreadsheet to store the information. This allowed the reporters to enter the information online themselves. I could then go into the spreadsheet, edit the text and make sure it was formatted correctly. We then used Tabletop.js to import the data into our app and Handlebars.js to template it.

The basic setup for the app is available on my Github page. This is a very similar setup mentioned in my last blog post.

Before the app went live, I exported all the data in the Google spreadsheet into JSON format using a method mentioned here. I did this for two reasons: 1) It spend up the load time of the app because browsers didn’t have to connect to the spreadsheet, download the data, format the data into JSON (which is what Tabletop.js does with the data in this app) and then display it online using templates rendered in Handlebars.js. Instead, it’s already downloaded, formatted into JSON and ready to be templated. And: 2) Tabletop.js has a bug that may cause some readers not to see any of the data at all. I wanted to avoid this problem.

The night of the election, we wanted to update the election results live. And we wanted to use the same app to display the results. Fortunately, the process was easy to do: I added new columns in our spreadsheet for vote totals and precincts reported. The new data was then pulled into our app and displayed with simple bar charts.

To display the results live, we had to ditch the exported JSON data and use the Google spreadsheet to power the app. This allowed us to update the spreadsheet and have the results display live on our website. We had one reporter at the county courthouse who punched in numbers for our Waterloo and Cedar Falls races. We had another reporter in Waverly who punched in results for races in that town. And we had another reporter in the newsroom who was monitoring the races in rural towns and giving me updated election results to enter into the spreadsheet.

The workflow worked great. While most news outlets were waiting for the county websites to update with election results, we were able to display the results right away. Unfortunately, the Black Hawk County website never wound up working on election, making our app the only place readers could go to get election results.

Our effort paid off: The app received about 11,500 pageviews, with about 10,000 of those pageviews coming the night of election (about 7,000 pageviews) and the following day. The app was more popular than any single story on our website for the month of October and November.

Reporters at the party headquarters said many of the candidates first tuned into the local television station to get election results but quickly went to our webpage when they realized we were the only ones with updated results. In fact, Waterloo’s mayor found out he won his race by looking at our website. Here’s a photo of him checking out our website on election night.

Which leads me to my last point: You’ll notice how our mayor is checking out the results on a smartphone. Our app (like all of our apps) was responsively designed, which means it looks great on mobile phones. It’s critical that news producers make sure their apps work on mobile. It’s pretty much mandatory. Because as our mayor shows, people love checking the news on their phones.

Written by csessig

November 10, 2013 at 10:19 pm

New code: Using a Google spreadsheet to power a mobile site

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I’ve posted a new template on Github that I hope others will find useful. It involves using Tabletop.js to transfer data from a Google spreadsheet onto a mobile website. I’ve tried to create it so you have to do little tweaking of the code that grabs and formats the data so you can focus on collecting and cleaning the data. The template will render the same regardless of what data is in the Google spreadsheet.

It’s initial purpose was to power our guides to weekend festivals, since we have quite a few in the summer. We used it, for instance, for our guide to the National Cattle Congress fair, which was last weekend. And it was designed for mobile users, in particular. You will notice how the website kind of looks like an app you would download on your smartphone with navigation buttons at the button. But it was responsively designed so it will work on all computer sizes.

You can use it for whatever you like. You can also change the code to have the data displayed as you see fit. The whole project is open-sourced.

The code can be found here. If you use it at all, please e-mail a link to you work so I can share it with the world! My e-mail is chris.essig@wcfcourier.com.

Written by csessig

September 18, 2013 at 10:47 am

Creating responsive maps with Leaflet, Google Docs

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wloo_history_teaserNote: This is cross-posted from Lee’s data journalism blog, which you can read over there by clicking here.

Quick: Name five people you know who don’t have a smartphone.

Stumped? Yeah, me too. The fact is more and more people have smartphones and are using them to keep up with the world.

What does that mean for news app developers? We need to be especially conscience of the mobile platform and make sure everything we build for the web is compatible on the smallest of screens.

One great way to do this is creating apps through responsive design. The idea behind responsive design is creating one web page for all users, as opposed to making separate pages for desktop and mobile computers.

Then we simply add, rearrange, subtract or tweak features on a web page based on the size of the browser the user has when they are viewing the app.

Maps can be difficult to manage on mobile platforms, especially when you add in legends, info boxes, etc. But they are not impossible. Fortunately Leaflet, an alternative to Google maps, is designed to work especially well on mobile platforms.

In this example, we will be loading data into a Google spreadsheet and using Leaflet to map the data on a responsive map.

1. Learn a little bit of Leaflet

Before we start, it would probably be best if you familiarize yourself with Leaflet. Fortunately, their website has some wonderful walk-throughs. I’d recommend going through this one before going anything further.

2. Grab the code

Now, go to my Github page and download the template.

The Readme file includes instructions on how to set up a basic map using Google spreadsheets and Tabletop.js, which is a wonderful tool that allows us to do all kinds of things with data in a Google spreadsheet, including map it using Leaflet.

3. Edit your index.html page

After you have followed the instructions on my Github page, you should have a map ready to go.

All you have to do is go into the index.html page and edit the title of the map, as well as add your own information into the “sidebar_content” div. Also make sure you add your name to the credits because you deserve credit for this awesome map you are putting together.

4. How does it work?

Now open up your map in a browser. If you rearrange the browser window size, you’ll notice that the map rearranges its size. The other components on the page also automatically readjust.

Some of this is done with the Bootstrap web framework, which was designed with responsive designing in mind.

I’ve also added my own CSS. One easy thing I’ve done with elements on the page is declare their widths and heights using percentages instead of pixels. This ensures that the components will automatically be adjusted regardless of the screen size.

Take a look at our css/styles.css file to get an idea of what I’m talking about: 

/* Body */
body {
    padding-left: 0px;
    padding-right: 0px;
  margin: 0;
    height: 100%;
}

html {
	height: 100%;
}


/* Map */
#map {
	position: absolute;
	float: left;
	top: 1%;
	height: 98%;
	width: 100%;
	z-index: 1;
}

The map’s height is 98 percent and width is 100 percent, ensuring it changes its size when the browser changes its size. If we set it to 600 pixels wide, the map would stay 600 pixels wide, even when the browser was adjusted.

– You’ll notice some other changes. For instance, if you have a wide screen, the map’s sidebar will be on the right side of the screen. We did this by using absolute positioning to place the sidebar and its content on the page:

/* Sidebar */
#sidebar {
  position: absolute;
	top: 2%;
	right: 1%;
	height: 96%;
	width: 30%;
	z-index: 2;
	border: 1px solid #999;
	padding-left: 1%;
	padding-right: 1%;
	background-color: #FFFFFF;
    background-color:rgba(255,255,255,0.9);
}

#sidebar h3 {
	line-height: 30px;
}

#sidebar_content {
	float: left;
	width: 30%;
	height: 70%;
	position: fixed;
	overflow: auto;
	padding-top: 5px;
}

The sidebar’s “right” position is set to 1 percent. This ensures that the sidebar will appear only 1 percent from the right side of the page. Additionally, its “top” position is set to 2 percent. This, effectively, pushes it to the top right corner of the screen.

We also used percentages to declare widths, heights and padding lengths for the sidebar.

– You’ll also notice when your browser is reduced drastically, the content of the sidebar disappears off the page. Instead, we have just the title of the sidebar at the top of the page. This is done with CSS media queries:

/* Styles from mobile devices */
@media (max-width: 625px) {
  
  #sidebar_content {
  	display: none;
	}

  /* Sidebar */
  #sidebar {
		position: relative;
		margin-top: 0%;
		float: left;
		left: 0%;
		right: 0%;
		top: 0%;
		padding-left: 2%;
		padding-right: 2%;
		height: 35px;
		width: 96.5%;
	}

}

Basically what the above code is saying is: If the browser is 625 pixels wide or smaller, apply the following CSS styles. These styles would therefore apply to almost all mobile phones. So what you are saying to the browser is: If this is a mobile browser, apply these styles to the elements on the page.

The first thing we do is hide the “sidebar_content” div, which is within our main “sidebar” div. Besides the “sidebar_content” div, we also have a div within the “sidebar” div called “sidebar_header” for our title. The template sets the title to “Tabletop to Leaflet” initially, although you should change that to match your project.

We hide the “sidebar_content” div with the property “display: none.” Hiding it ensures that the only thing left in our “sidebar” div is the title. Then the sidebar is pushed to the top left corner of the page using absolute positioning.

So what do we do with that information we have hidden? We put it in another div using some Javascript. Then we toggle that div from hidden to visible using a button with the class “toggle_description.” This toggle feature is enabled using jQuery.

From our js/script.js file:

// Toggle for 'About this map' and X buttons
// Only visible on mobile
isVisibleDescription = false;
// Grab header, then content of sidebar
sidebarHeader = $('#sidebar_header').html();
sidebarContent = $('#sidebar_content').html();
// Then grab credit information
creditsContent = $('#credits_content').html();
$('.toggle_description').click(function() {
  if (isVisibleDescription === false) {
		$('#description_box_cover').show();
		// Add Sidebar header into our description box
		// And 'Scroll to read more...' text on wide mobile screen
		$('#description_box_header').html(sidebarHeader + '<div id="scroll_more"><strong>Scroll to read more...</strong></div>');
		// Add the rest of our sidebar content, credit information
		$('#description_box_content').html(sidebarContent + '<br />' + 'Credits:' + creditsContent);
		$('#description_box').show();
		isVisibleDescription = true;
	} else {
		$('#description_box').hide();
		$('#description_box_cover').hide();
		isVisibleDescription = false;
	}
});

The above code first grabs the information from the “sidebar_content” div, then places it in the “description_box” div. It also sets our toggle function, which is activated when the user clicks on the button with the class “toggle_description.”

– The “description_box” div is also styled similarly to the “sidebar” div. The big difference is the “description_box” div is hidden by default because we only want it shown if we are on a mobile phone. The button with the class “toggle_description” is also hidden by default.

From our css/styles.css file:

/* 'About this map' button, description box */
/* Mobile only */
.toggle_description {
  display: none;
	z-index: 8;
	position: relative;
	float: right;
    right: 0%;
    top: 0%;
}

#description_box_cover {
	display: none;
	z-index: 10;
	position: absolute;
	top: 0%;
	width: 100%;
	height: 100%;
    background-color: #444444;
    background-color:rgba(44,44,44,0.9);
}

#description_box {
	position: absolute;
	display: none;
	z-index: 11;
	width: 92%;
	height: 93%;
	padding-top: 1%;
	padding-left: 1%;
    padding-right: 1%;
    left: 2.5%;
    top: 2.5%;
    border: 1px solid #999;
    background-color: #FFFFFF;
    background-color:rgba(255,255,255,0.9);
}

#description_box h3 {
	padding-bottom: 0px;
	line-height: 15px;
}

Now we do the opposite with the “toggle_description” when compared to what we did with the “sidebar_content” div.

With the “sidebar_content” div, we had it shown by default then hidden on mobile phones using CSS media queries. With the button, we hide it by default and then show it on mobile phones using a CSS property of “display: inline.”

From our css/styles.css file:

/* Styles from mobile devices */
@media (max-width: 625px) {

	.toggle_description {
		display: inline;
	}

}

As a noted above, when someone clicks on that button, jQuery toggles between hidden and shown on the button with the class “toggle_description”. It is hidden by default, so it is shown when the user first clicks  it. Then when the user clicks the blue X button (which also has the class of “toggle description”), the box disappears.

A similar philosophy is in place to hide and show the credits box.

That should give you a good idea of what is happening with this map. Feel free to fork the repo and create your own awesome maps.

Have any questions? Don’t hesitate to leave a comment.

How-to: Creating a public salary database

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before_after_teaserNote: This is cross-posted from Lee’s data journalism blog, which you can read over there by clicking here.

People love knowing what public employees earn in a year. They always make for interesting conversation and plenty of controversy.

In honor of Sunshine Week, I’m going to go through the steps of creating a quick and dirty salary database using DataTables.

Here’s the process:

1. Find a data set and clean, clean, clean

For this example, I’m going to use the 2012 Salary Book for public employees in Iowa. The spreadsheet has records for more than 59,000 public employees. And there are plenty of things in the spreadsheet you’ll probably want to clean up.

I’m not going to dive too deeply into cleaning data here except to point out that it is VERY IMPORTANT. I like to first bring my spreadsheets into Excel and simply sort each row from A to Z to find empty cells, cells with funky text or characters, etc. Here’s a handy guide for cleaning data in Excel.

I then use a great program called Open Refine (formerly Google Refine) to help clean the data. Their website includes some video tutorials on how to use the program. Be sure to also read this post on how investigative journalists should use Refine. Finally, this walkthrough also teaches journalists to use Refine.

The process of cleaning data is probably the most important step in creating a database. It make take several hours. But just as you wouldn’t print a story without first proofreading it, you shouldn’t make data available on your site that you haven’t cleaned to the best of your abilities.

2. Hosting your data

When you’re done cleaning the data, you’ll export the spreadsheet in Google Refine. You’ll then you’ll need to upload the data and host it somewhere. You have a few options:

a. Don’t host it at all. Instead follow this method I mentioned in an earlier blog post that converts the spreadsheet into an HTML table, which is then converted into a DataTable. The disadvantage of this method is if you want to update the spreadsheet, you’ll have to do the conversion over and paste the new HTML table into your document. For spreadsheets that are changed repeatedly, this could be a pain.

b. Upload the spreadsheet into Google Drive and use an awesome service called Tabletop.JS to feed the spreadsheet to DataTables. This is quickly becoming one of my preferred ways to host data simply because it allows several journalists and editors to edit the same Google spreadsheet. All their changes will be reflected on your page, which will be updated automatically as the spreadsheet is updated.

And in fact, my hope was to upload our spreadsheet of Iowa public employee salaries to Google and use Tabletop.JS for this project. But I couldn’t because Google only allows spreadsheets with less than 400,000 fields. This spreadsheet, which was 59,000 rows and seven columns, just eclipses Google’s limit.

For an example of Tabletop.JS in action, check out this repo on my Github page. If you have any questions on how it works, shoot me an e-mail or leave a comment on this article.

c. You can also use an open source tool called DataSet from the Miso Project. Instead of hosting it with Google, you just load the CSV file on your own server and pull the data directly from the file. You can convert the CSV information into Javascript arrays, objects, etc., which allows the data to work with DataTables and tons of other awesome Javascript libraries.

The advantage to DataSet is you can work with huge spreadsheets like this one on Iowa public employee salaries and you don’t have to worry about Google’s size limits. The downfall is only one person can edit the spreadsheet at a time. And they’ll have to download the CSV, re-save it, then re-upload it to the server every time they make a change.

3. The code

The first thing you’ll need to do is go to my Github page and download the directory for this project.

I’m going to break down the Javascript file into chunks to give you an idea of what is happening:

// DataTables currency
// Use to sort the table via currency
jQuery.extend( jQuery.fn.dataTableExt.oSort, {
	"currency-pre": function ( a ) {
		a = (a==="-") ? 0 : a.replace( /[^\d\-\.]/g, "" );
		return parseFloat( a );
	},
	
	"currency-asc": function ( a, b ) {
		return a - b;
	},
	
	"currency-desc": function ( a, b ) {
		return b - a;
	}
});

This function allows us to sort the table based on currency. Basically, when the reader firsts loads the database, the employee with the highest salary will be shown. For more information on the different sorting techniques offered by DataTables, click here.

// Where we'll put the data
var newDataSet = [];
 
// Our column headers
// Change these to fit your table
var tableColumnSet =   [
  { "sTitle": "Employee" },
	{ "sTitle": "Department" },
	{ "sTitle": "Total FY12 Salary", "sType": "currency" },
	{ "sTitle": "Gender", "sClass": "center" },
	{ "sTitle": "County", "sClass": "center" },
	{ "sTitle": "Position", "sClass": "center" }
];

This creates a blank array called “newDataSet.” Later, we will push all of the content in our CSV into this array, which will be used by DataTables and displayed on the page. The “tableColumnSet” variable is where we set our column header names. For future projects, you’ll want to change those to match your own CSV file.

Notice also how we set the “Total FY12 Salary” column to currency, which allows us to sort the table by currency.

// Our DataTable information
// Don't need to change anything here
// Unless you want to customize the table format
function showInfo() {
  $('#table_div').html( '<table cellpadding="0" cellspacing="0" border="0" class="table table-striped table-bordered" id="table"></table>' );
 
	// Push the data to the table
	$('#table').dataTable( {
		"bProcessing":true,
		"sPaginationType": "bootstrap",
		"iDisplayLength": 100,
		"aaData": newDataSet,
		"aoColumns": tableColumnSet,
		// Pick which column we will sort by default
		// For this table, we'll sort ascending by Total FY12 Salary
		"aaSorting": [[ 2, "desc" ]],
		"oLanguage": {
			"sLengthMenu": "_MENU_ records per page"
		}
	});
}

DataTables provides us with several different options for displaying the data, including how to sort the data, where to the pull the data from, how many rows to show at a time, etc. We’re putting all this in a function called “showInfo”, which we will call below.

For more on the options available to us with DataTables, click here.

You may also notice that this table is styled using Twitter’s Bootstrap framework. Basically that gives the table the zebra look to it, as well as style the buttons and search field. For more information on working with Bootstrap, click here.

// Load up the CSV using Miso.Dataset
$(document).ready( function() {
  // Change URL to the right path for your CSV
	var ds = new Miso.Dataset({
  		url : 'csvs/salary_book_clean.csv',
  		delimiter : ','
  	});
 
	// Run this after we load our CSV
	ds.fetch({ success : function() {
    	this.each(function(row, rowIndex) {
    		// Change these variables to match your column names
    		var employeeData = row.Employee;
    		var departmentData = row.Department;
    		var salaryData = row.TotalFY12Salary;
    		var genderData = row.Gender;
    		var countyData = row.County;
    		var positionData = row.Position;
    		// Put information in an array and push it to our table
    		// Change these variables to match variables above
    		var myArray = [employeeData, departmentData, salaryData, genderData, countyData, positionData];
			newDataSet.push(myArray);
  		});
    	// Call DataTable function showInfo
		showInfo();
	}});
});

The last part of this file will load when our document is ready. It uses Miso’s DataSet library to pull in the information from our CSV file. Once the information is loading, a loop for each row in our data. A Javascript array is created for each row containing that row’s data and then that is pushed to our newDataSet variable, which we created earlier.

For future projects, make sure you change the variable names in each loop to fit your CSV file. So change the words “Employee”, “Department”, etc. to make the column headers in your CSV file.

Finally, once that is done, we call our “showInfo” function, which puts the content in our CSV on the page using DataTables.

If you have any questions, feel free to leave me a comment or e-mail me directly at chris.essig@wcfcourier.com.

Written by csessig

March 15, 2013 at 10:03 am

Final infographics project

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For the last six weeks, I’ve taken a very awesome online course on data visualization called “Introduction to Infographics and Data Visualization” It is sponsored by the Knight Center for Journalism in Americas and taught by the extremely-talented Albert Cairo. If you have a quick second, check out his website because it’s phenomenal.

Anyways, we have reached the final week of the course and Cairo had us all make a final interactive project. He gave us free reign to do whatever we want. We just had to pick a topic we’re passionate about. Given that I was a cops and courts reporter for a year in Galesburg, Illinois before moving to Waterloo, Iowa, I am passionate about crime reporting. So I decided for my final project I’d examine states with high violent crime rates and see what other characteristics they have. Do they have higher unemployment rates? Or lower education rates? What about wage rates?

Obviously, this is the type of project that could be expanded upon. I limited my final project to just four topics mostly because of time constraints. I work a full time job, you know! Anyways, here’s my final project. Let me know if you have any suggestions for improvement.

teaser

About:

Data: Information for the graphic was collected from four different sources, which are all listed when you click on the graphic. I took the spreadsheets from the listed websites and took out what I wanted, making CSVs for each of the four categories broken down in the interactive.

Map: The shapefile for the United States was taken from the U.S. Census Bureau’s website. Find it by going to this link, and selecting “States (and equivalent)” from the dropdown menu. I then simplified the shapefile by about 90 percent using this website. Simplifying basically makes the lines on the states’ polygons less precise but dramatically reduces the size of the file. This is important because people aren’t going to want to wait all day for your maps to load.

Merging data with map: I then opened that shapefile with an awesome, open-source mapping program called QGIS. I loaded up the four spreadsheets of data in QGIS as well using the green “Add vector layer” button (This is important! Don’t use the blue “Create a Layer from a Delimited Text File” button). The shapefile and all the spreadsheets will now show up on the right side of the screen in QGIS under “Layers.”

Each spreadsheet had a row for the state name, which matched the state names for each row in the shapefile.  It’s important these state names match exactly. For instance, for crime data from the FBI I had to lowercase the state names. So I turned “IOWA” into “Iowa” before loading it into QGIS because all the rows in the shapefile were lowercase (“Iowa” in the above example).

Then you can open the shapefile’s properties in QGIS and merge the data from the spreadsheets with the data in the shapefile using the “Joins” tab. Finally, right click on the shapefiles layer then “Save As” then export it as a GeoJSON file. We’ll use this with the wonderful mapping library Leaflet.

qgis_teaser

Leaflet: I used Leaflet to make the map. It’s awesome. Check it out. I won’t get into how I made the map interactive with Javascript because it’s copied very heavily off the this tutorial put out by Leaflet. Also check it out. The only thing I did differently was basically make separate functions (mentioned in the tutorial) for each of my four maps. There is probably (definitely) a better way to do this but I kind of ran out of time and went with what I had. If you’re looking for the full code, go here and click “View Page Source.”

Design: The buttons used are from Twitter’s Bootstrap. I used jQuery’s show/hide functions to show and hide all the element the page. This included DIVs for the legend, map and header.

GeoJSON: The last thing I did was modify my GeoJSON file. You’ll notice how the top 10 states for violent crime rates are highlighted in black on the maps to more easily compare their characteristics across the maps. Well, I went into the GeoJSON and put all those 10 states attributes at the bottom of the file. That way they are loaded last on the map and thus appear on top of the other states. If you don’t do this, the black outlines for the states don’t show up very well and look like crap. Here’s GeoJSON file for reference.

Hopefully that will help guide others. If you have any questions, feel free to drop me a line. Thanks!

 

Written by csessig

December 11, 2012 at 12:13 am