Tag: Disability

By Posted on Posted in Free, PDRater No Comments Tagged with , , , , , ,

Well, the title really says it all.

This website was re-launched on July 6, 2008.  While all of the permanent disability and workers’ compensation benefits calculators are still free, a quick and simple registration process is now required to use them.

In the 33 business days from July 7, 2008 through August 20, 2008, one hundred people have registered for free access to this website.  I like to think that’s pretty good.

My totally unscientific research has revealed this website’s users to be:

  • Well above average in intelligence;
  • Have extremely discriminating taste;
  • And, not at all susceptible to flattery

By Posted on Posted in AJAX, Javascript, MySQL, PDRater, PHP, Technobabble No Comments Tagged with , , , , , , , , , , , , , ,

I recently gave a brief overview of my permanent disability and workers’ compensation benefit calculators. In that post I wrote a little bit about how my online benefits calculators work. Since then I’ve posted about my use of javascript and PHP in creating these permanent disability and permanent impairment calculators.

As I’ve mentioned in those prior posts, both javascript and PHP have inherent downsides. My very first attempt at online benefits calculators using javascript and ASP actually suffered from all of the downsides of javascript and PHP. Those first calculators used tons of user’s computers’ resources, bandwidth, and server power. However, learning more about AJAX enabled me to build a set of calculators which benefited from the strengths of javascript and PHP while minimizing, if not eliminating, their weaknesses.

The acronym “AJAX” refers to “asynchronous javascript and XML” – a collection of other technologies which allow a webpage to communicate with a web server without requiring an entire page download.

Example 1: A calculator without AJAX calculating “6 x 7” would send information to be calculated to the web server. The web server would then respond by giving you an entirely new page with the answer, “42”. However, in order to download that answer you would need to download a whole new page – and all the images, text, and code associated with it. Even a normal web page could be between 30,000 and 300,000 bytes in size. ((A download of “www.google.com” was approximately 30,000 bytes and a download of “www.yahoo.com” was approximately 300,000 bytes.))

Example 2: A calculator with AJAX calculating “6 x 7” would send information to be calculated to the web server. The web server would then respond by sending back just the answer, “42”. This would be 2 bytes.

If my calculators needed to download of 300 kilobytes for every single operation, a simple calculation could take about 30 seconds on dialup and a full 1 second on broadband. Although 1 second doesn’t seem like a long time – it is in the internet age. Most of the calculations on this site take approximately .500 seconds using a broadband connection. I would guess that about 90% of that time is due to network latency/network lag – which wouldn’t be much different for a dialup connection.

For the first few months after the launch of this website, it did not use a MySQL database. I actually went to some pretty ridiculous extremes to not have to learn a new programming language. I eventually gave in, learned how to use MySQL and am a better programmer for it.

Next up, MySQL!

By Posted on Posted in AJAX, Javascript, PDRater, PHP, Technobabble No Comments Tagged with , , , , , , , , , , , , , ,

I recently gave a brief overview of my permanent disability and workers’ compensation benefit calculators. In that post I wrote a little bit about how my online benefits calculators work. My last post in this series was about how and why these permanent disability and workers’ compensation benefits calculators use javascript.

I had tried Microsoft’s ASP (active server pages) in experimenting with a prior version of my permanent impairment calculators, and while functional, the coding was a complete mess since I didn’t fully understand what I was doing. To make matters worse, the only manuals on ASP I could find gave examples using VBScript – which is MS’s version of javascript. ((Can’t we all just get along?))

Just over a year ago a friend of mine encouraged me to try PHP. (Thanks Johnny!) Its syntax, the way in which you write code, is very similar to javascript and was fairly easy to learn.

Unlike javascript, PHP is run only on the web server. There are a lot of benefits to moving all of the calculations from being performed by a user’s computer to my web server:

  • Uniformity. All calculations will always be performed by the web server in the same exact way – irrespective of the user’s computer.
  • Speed. Since all calculations are performed on the web server, the user’s computer doesn’t need to do any number crunching.
  • Protection. All of the formulas, tables, and magical incantations used to generate the calculations are kept only on the web server.

But, PHP isn’t without its downsides:

  • PHP is being used to perform a calculation, even when javascript would be faster. Javascript takes longer to crunch the answer, but you have to “wait” for PHP to send a request to the server and wait for the answer. ((I say “faster,” but we’re talking about the difference between 10 milliseconds for javascript to calculate the answer and waiting 400 milliseconds for the server to return the answer.))
  • A pure PHP calculator would require the user to send the web server the entire page and wait for a whole new page to load. Every calculation would take a full second or more using a pure PHP calculator. ((A second might not seem like a long time – but it is when you’re using a computer. I’d bet that if these calculators took 1 second for everything (such as finding an occupational code or work restriction) no one would use them.))
  • When PHP is used to perform handle all calculations, there is more of a strain on the web server itself.

Using AJAX (more on this later) to create workers’ compensation benefits calculators has allowed me to take advantage of all of the strengths of javascript and PHP and minimize the negatives of these technologies.

Next up, AJAX!

By Posted on Posted in Downloads, Javascript, PDRater, Technobabble No Comments Tagged with , , , , , , , , , , , , , ,

I recently gave a brief overview of my permanent disability and workers’ compensation benefit calculators. In that post I wrote a little bit about how my website calculators work.

In late 2004 I spent some of my free time working on a calculator for the 1997 Permanent Disability Rating Schedule 100% pure javascript (the only programming language I knew at the time). I had several reasons for never publicly releasing this calculator:

  • Uniformity. Not all computers and browsers perform all javascript functions the same way.
  • Speed. A pure javascript calculator would require the user to download all of the code – not just the parts they needed.
  • Protection. Anyone with a modicum of technical knowledge could simply downloaded the calculators, and then post it as their own.
  • Obsolete. With SB 899 and the 2005 Permanent Disability Rating Schedule, my calculator became nearly obsolete. I scrapped it rather than building a second calculator.

The current workers’ compensation benefits calculators use very very little javascript. Doing so has meant that I don’t have to worry about different computers/browsers, users only need to download the code they need to run a single calculation, and my calculators don’t work without my server.

Next up, PHP!

By Posted on Posted in PDRater, Technobabble No Comments Tagged with , , , , , , , , , , ,

Here’s a (simplified) overview of how my permanent disability/impairment and workers’ compensation benefits calculators work. As I’ve mentioned elsewhere, I wrote these website calculators using javascript, PHP, MySQL, and AJAX.

In a recent post, I created a really simple test for cell phones using the above languages. Here’s what was happening:

  • The user clicks the button “Cell Test.”
  • The javascript embedded in the button detects the “click.”
  • The javascript embedded in the button then tells an AJAX program that the button was clicked.
  • AJAX sends a little bit of information to the web server – saying that the user clicked that button.
  • The PHP program on the server is notified that the button was clicked.
  • The PHP program checks a MySQL table to see what it should happen when that button is clicked.
  • The MySQL table returns the answer, what should happen when a button is clicked, to the PHP program.
  • The PHP program takes the answer from the MySQL table and sends it back to the AJAX program.
  • The AJAX program takes that information and, using a little bit of javascript, displays the answer in your web browser.

Easy!