Category: Tools

Be your own traffic and road planner

October 16, 2012 / / 0 Comments

Wanna know how many cars were measured to pass by on a street near you (in Chicago)?

Want to know how wide a street is?
Want to do this without leaving your house?

You can.

1. Find the “ADT” (average daily traffic) for roads in Chicago on the city’s Traffic Tracker website. Average is a misnomer, though, because that implies more than one count has been taken or estimate has been made. The last time the city counted cars in Chicago was 2006; I imagine the difference in counts taken this year would be statistically significant (meaning any differences would not be by chance or random).

To find a location in Traffic Tracker:

  1. You can pan and zoom the map until you find it, or you can select one street and then select an intersection street and click the magnifying glass.
  2. Then click the checkbox next to Traffic Signals.
  3. Click on a green dot (with number label) to find direction counts and the count date.

Okay, now let’s measure the street width.

Google Earth and Maps have this tool. For Google Earth, it’s as simple as finding the ruler tool in the toolbar, selecting your units, and then clicking on the start and end points. The distance will also be displayed live as you move your cursor.

Finding the distance in Google Maps has a few more steps:

  1. Turn on the measurement tool, in Maps Labs. Go to Google Maps and click “Maps Labs” at the bottom of the left pane.
  2. In the popup dialog pane, click the radio button next to “Enable” for Distance Measurement Tool.
  3. Click Save Changes.
  4. Find the street you want to measure.
  5. Click the ruler button in the lower left corner of the map.
  6. Click one side of the street and then click the other side of the street. You can keep clicking to get distances of a polyline (a multi-segmented line) that you draw.
  7. Change the map units to your desire (there are tens of archaic ones available).

Now you’ve got two more tools with which to arm yourself in understanding your streets and your neighborhood.

Some reasons why the CTA doesn’t make its own mobile apps

October 10, 2012 / / 0 Comments

Where’s the train?

“Twitter updated their app and now it sucks”. (Here’s some evidence.)

Have you heard that before? Thankfully there are tens – perhaps hundreds – more options to post to and read Twitter on your appy device.

The Chicago Transit Authority provides 1.7 million rides per day. A lot of passengers like to know where the trains and buses are. And it’s possible to know with many tools like Bus Tracker and Train Tracker, both of which are available through APIs, SMS, and websites.

Some people (eh, I can’t exactly point out who right now) have noted (complained?) that the CTA doesn’t make its own app for smartphones and tablets. I’m glad they don’t!

Here are more reasons why the CTA doesn’t make its own mobile apps:

  1. It would be racist of the CTA. (Pretty much everything the CTA does is racist according to someone but making an app would only be useful to those with compatible devices, so it’s probably more accurate to say income discrimination.)
  2. Bus service is getting cut but they’re spending money on making apps.
  3. There are 4 platforms to write apps for (at least 4 – not sure if any CTA passengers would demand Symbian or webOS).

The best reason?

Developers can do it better. So the CTA gives them the tools.

Customer reviews for my bike map app

July 15, 2012 / / 0 Comments

Only reviews left for the current version are displayed on the iTunes Preview page, and the default view of the iTunes Store. 

I’m appreciative of the two reviews people have left for my app – it’s a bike map for Chicago stored in your phone, download in iTunes. Their positivity and the slight increase in sales this past week has increased the ranking of my app. I don’t know what the ranking means.

When my app first ranked, in its Reference category, it was 385, then 289, and now stands at 315. I’m not sure on what factors the ranking is based, but I’ve gathered some clues from other bloggers:

[In addition to the number of downloads, other] factors play into the ranking equation such as how long the app is opened as the active app and how often the app is opened.

There’s no mention of reviews on that page, but I found another article that mentions more ways to improve your app, which includes having positive reviews. (Another factor it mentions is frequently updating the app.)

I’d like to hear from my app’s users what their feedback is before they leave a review in the iTunes Store. I can address issues directly with users and discuss how they can (or cannot) be incorporated in a future update to the app. You can send your feedback to me, and your love to the app store. (A major downside of the customer reviews process in the iTunes Store is the inability for the developer to respond.)

My app’s received two reviews (both 5 stars!) so far:

Saw this app being discussed on Twitter and thought I’d check it out. So, on the hottest day of 2012, I jumped on my bike and rode around my area checking out the apps features. Color me impressed! I rode to a few areas that I was not over familiar with and activated the app to peruse my options via my bike (or CTA). I look forward to using this on my far south/far north bikiing adventures soon!

The first reviews about the first version:

Would be great if it could locate on the map with GPS. Also if it could zoom out more. These bike lanes have come a long way recently. There are some really nice new places to ride like the cycle track on Kinzie. But there are also some old routes out there that are great biking such as the Boulevard System (Humboldt, Logan, Palmer Sq) that you could show on your map. And it says it supports German, but it is in English 🙂

The part about my app being available in German was true for v0.1, but I’ve fixed that for v0.2. If you’re going to leave a review, I’d like to leave you with this advice, for I feel it makes for a constructive review:

  1. Describe what is good about the app, and what you like about the app.
  2. Describe how you’ve used the app.
  3. Suggest ways the app could improve.

This was what the first version looked like. It wasn’t very good. 

How to split a bike lane in two and copy features with QGIS

July 13, 2012 / / 0 Comments

A screenshot of the splash image seen on users with iPad retina displays in landscape mode. 

To make the Chicago Offline Bike Map, I need bikeways data. I got this from the City of Chicago’s data portal, in GIS shapefile format. It has a good attribute table listing the name of the street the bikeway is on and the bikeway’s class (see below). After several bike lanes had been installed, I asked the City’s data portal operators for an updated shapefile. I got it a month later and found that it wasn’t up-to-date. I probably could have received a shapefile with the current bikeway installations marked, but I didn’t have time to wait: every day delayed was one more day I couldn’t promote my app; I make 70 cents per sale.

Since the bikeway lines were already there, I could simply reclassify the sections that had been changed to an upgraded form of bikeway (for example, Wabash Avenue went from a door zone-style bike lane to a buffered bike lane in 2011). I tried to do this but ran into trouble when the line segment was longer than the bikeway segment that needed to be reclassified (for example, Elston Avenue has varying classifications from Milwaukee Avenue to North Avenue that didn’t match the line segments for that street). I had to divide the bikeway into shorter segments and reclassify them individually.

Enter the Split Features tool. QGIS is short on documentation and I had trouble using this feature. I eventually found the trick after a search that took more time than I expected. Here’s how to cut a line:

  1. Select the line using one of the selection tools. I prefer the default one, Select Features, where you have to click on the feature one-by-one. (It’s not required that you select the line, but doing so will ensure you only cut the selected line. If you don’t select the line, you can cut many lines in one go.)
  2. Toggle editing on the layer that contains the line you want to cut.
  3. Click Edit>Split Features to activate that tool, or find its icon in one the toolbars (which may or may not be shown).
  4. Click once near where you want to split the line.
  5. Move the cursor across the line you want to split, in the desired split location.
  6. When the red line indicating your split is where you desire, press the right-click mouse button.

Your line segment has now been split. A new entry has been added to the attribute table. There are now two entries with duplicate attributes representing that together make up the original line segment, before you split it.

This screenshot shows a red line across a road. The red line indicates where the road will be split. Press the right-click mouse button to tell QGIS to “split now”.

After splitting, open the attribute table to see that you now have two features with identical attributes. 

Copying features in QGIS

A second issue I had when creating new bikeways data was when a bikeway didn’t exist and I couldn’t reclassify it. This was the case on Franklin Boulevard: no bikeway had ever been installed there. I solved this problem by copying the relevant street segments from the Transportation (roads) shapefile and pasted them into the bikeways shapefile. New entries were created in the attribute table but with blank attributes. It was simple to fill in the street name, class, and extents.

Chicago bikeways GIS description

Bikeway classes (TYPE in the dataset) in the City of Chicago data portal are:

  1. Existing bike lane
  2. Existing marked shared lane
  3. Proposed on-street bikeway
  4. Recommended bike route
  5. Existing trail
  6. Proposed off-street trail
  7. Access path (to existing trail)
  8. Existing cycle track (also known as protected bike lane)
  9. Existing buffered bike lane

It remains to be seen if the City will identify the “enhanced marked shared lane” on Wells Street between Wacker Drive and Van Buren street differently than “existing marked shared lane” in the data.

Stats from the OECD: Comparing traffic injuries of the United States and Netherlands

May 21, 2012 / / 0 Comments

For an article I’m writing for Architect’s Newspaper about the Chicago Forward CDOT Action Agenda, I wanted to know about traffic injuries and fatalities in the United States, but compared to the Netherlands and Denmark and other places with a Vision Zero campaign (to have 0 traffic deaths each year).

I already knew the OECD had a good statistics database and web application. With a few clicks, I can quickly get a table of traffic injuries (casualties) listing just the countries I want. I can easily select the years I want, too.

In one more click the web application will show a time animated bar chart. A feature I’d like to see added is dividing the figure (in this case traffic injuries) by the population. Check out the video to see what it looks like. The United States looks to be in terrible shape, but our country has several times more residents.

I had trouble downloading and opening the CSV file of the data table I created. The XLS file was damaged, also. The built-in Mac OS X Archive Utility app couldn’t open the .gz file, but I used The Unarchiver app successfully.

My calculations, based on data from OECD (national population and traffic fatalities), Illinois Department of Transportation (IDOT), and the American Community Survey:

Fatalities per 100,000 in 2009

  • United States: 11.02472
  • Denmark: 5.48969
  • Netherlands: 4.35561
  • Sweden: 3.84988
  • Chicago: 16.74891
  • United Kingdom: 3.83555

Chicago’s fatality rate per 100,000 citizens in 2009 was 16.75 (473 deaths on the roads). The fatality rate dropped in 2010: just 11.65 deaths per 100,000 residents (315 deaths on the roads; the population also decreased).

Updated September 28, 2012, to add the United Kingdom.