Easy-to-follow video tutorials help you learn software, creative, and business skills.Become a member

Overview of my solution

From: Code Clinic: PHP

Video: Overview of my solution

If you think this task simply involves Then clicking the raw data link on the main And the environmental data for 2001 through to We can use PHP file manipulation functions to

Overview of my solution

If you think this task simply involves calculating mean and median averages, think again. Calculating the averages requires only a few lines of code and you're done. Now this task goes much deeper. Maybe not as deep as Lake Pend Oreille, but deep enough. Let's take a look at the way the Pend Oreille raw data is organized by going to the website. Then clicking the raw data link on the main page and it's deep more weather data that we want. And the environmental data for 2001 through to 2010 is stored in these large text files.

They range in size from about one and half megabytes. To this one for 2008, which is nearly seven megabytes. But if we look at the date for 2010, we can see that it comes to an end in late May. Thereafter, each measurement is in a separate file that contains just one day's data. So if we open this 2014 folder, we can see inside the series of other folders one for each day. And if we just open one at random we can see there are 11 files in there one for each different type of measurement.

We're interested in only three, air temperature, barometric pressure and wind speed. Getting and processing the data for one or two days can be done very quickly. But let's say someone requests a longer range. Even at several pages a second, the response is going to be too slow for a web service. And anyway the historical weather data is never going to change so it makes sense for a web service to cache it. So the approach that I took was to download the environmental data files for 2001 to 2010.

So let's go back to my editing program. And I've got them all stored here in the raw data folder. And I created a script to process them, to batch process them. Extracting the information that I wanted at inserting this into a database. Because the data is stored in a predictable format, PHP's file and string manipulation functions make it easy to crunch thousands of lines of data. But there's a nasty surprise. The data from 2007 is stored in a different format from proceeding years.

So this script needs to take account of that. The next task was to handle one day at a time. So I created a class which does exactly that. And then, ran it in a loop to get one year's data at a time. And this same class now updates the database automatically, once every 24 hours. The final part of the task was to create the web service. The great news is the PHP provides all the necessary tools. We can use PHP file manipulation functions to get the data from the Pend Oreille website.

With the help of string manipulation functions and loops, we can extract all the information we need and inserted directly into our database. Array functions and simple arithmetic calculate the mean and median averages. And building the web service uses a number of PHP features. Including grabbing variables from a query string, communicating with a database, and encoding adjacent output. There is a lot of coding involved, so let’s get on with it.

Show transcript

This video is part of

Image for Code Clinic: PHP
Code Clinic: PHP

47 video lessons · 4043 viewers

David Powers

Expand all | Collapse all
  1. 8m 49s
    1. Welcome
      1m 18s
    2. What you should know before watching this course
      4m 40s
    3. Using the exercise files
      1m 56s
    4. Getting the most from Code Clinic
  2. 1h 34m
    1. Introducing Lake Pend Oreille
      5m 4s
    2. Overview of my solution
      3m 22s
    3. Setting up the database
      4m 55s
    4. Retrieving the full-year records
      5m 20s
    5. Processing the full-year records
      10m 49s
    6. Priming the date_recorded column
      7m 47s
    7. Inserting the full-year data into the database
      6m 48s
    8. Processing individual days
      6m 54s
    9. Retrieving a year's data a day at a time
      7m 41s
    10. Keeping the data up to date
      4m 27s
    11. Calculating the mean and median values
      7m 21s
    12. Creating a web service
      6m 21s
    13. Getting the required data
      6m 50s
    14. Building the web service response
      10m 38s
  3. 49m 47s
    1. Identify the image subset
      3m 14s
    2. Overview of my solution
      3m 19s
    3. Setting up the files
      2m 43s
    4. Calculating the scaling ratio
      6m 28s
    5. Using a custom class to scale images
      6m 25s
    6. Generating the thumbnails
      7m 49s
    7. Using subimage-search in ImageMagick
      4m 32s
    8. Analyzing the image statistics
      4m 45s
    9. Finding the cropped images
      7m 13s
    10. Running the script and displaying the results
      3m 19s
  4. 39m 3s
    1. A classic CS interview question
      2m 4s
    2. Overview of my solution
      3m 48s
    3. Finding all possible combinations
      6m 26s
    4. Detecting horizontal attacks programmatically
      4m 8s
    5. Implementing the checkLayout() function
      6m 25s
    6. Rotating the chessboard
      4m 59s
    7. Eliminating duplicate solutions
      6m 34s
    8. Displaying the unique solutions
      4m 39s
  5. 21m 33s
    1. Build a musical instrument using mouse movements
      1m 35s
    2. Overview of my solution
      2m 1s
    3. Using the Web Audio API
      2m 47s
    4. Creating the tone generator
      7m 39s
    5. Controlling the frequency and volume
      7m 31s
  6. 31m 29s
    1. Searching directories for photos NEW
      2m 44s
    2. Overview of my solution NEW
      3m 24s
    3. Finding the images NEW
      5m 30s
    4. Extracting Exif and IPTC metadata NEW
      6m 18s
    5. Extracting XMP metadata NEW
      6m 22s
    6. Reorganizing the folder structure NEW
      7m 11s

Start learning today

Get unlimited access to all courses for just $25/month.

Become a member
Sometimes @lynda teaches me how to use a program and sometimes Lynda.com changes my life forever. @JosefShutter
@lynda lynda.com is an absolute life saver when it comes to learning todays software. Definitely recommend it! #higherlearning @Michael_Caraway
@lynda The best thing online! Your database of courses is great! To the mark and very helpful. Thanks! @ru22more
Got to create something yesterday I never thought I could do. #thanks @lynda @Ngventurella
I really do love @lynda as a learning platform. Never stop learning and developing, it’s probably our greatest gift as a species! @soundslikedavid
@lynda just subscribed to lynda.com all I can say its brilliant join now trust me @ButchSamurai
@lynda is an awesome resource. The membership is priceless if you take advantage of it. @diabetic_techie
One of the best decision I made this year. Buy a 1yr subscription to @lynda @cybercaptive
guys lynda.com (@lynda) is the best. So far I’ve learned Java, principles of OO programming, and now learning about MS project @lucasmitchell
Signed back up to @lynda dot com. I’ve missed it!! Proper geeking out right now! #timetolearn #geek @JayGodbold
Share a link to this course

What are exercise files?

Exercise files are the same files the author uses in the course. Save time by downloading the author's files instead of setting up your own files, and learn by following along with the instructor.

Can I take this course without the exercise files?

Yes! If you decide you would like the exercise files later, you can upgrade to a premium account any time.

Become a member Download sample files See plans and pricing

Please wait... please wait ...
Upgrade to get access to exercise files.

Exercise files video

How to use exercise files.

Learn by watching, listening, and doing, Exercise files are the same files the author uses in the course, so you can download them and follow along Premium memberships include access to all exercise files in the library.

Exercise files

Exercise files video

How to use exercise files.

For additional information on downloading and using exercise files, watch our instructional video or read the instructions in the FAQ .

This course includes free exercise files, so you can practice while you watch the course. To access all the exercise files in our library, become a Premium Member.

Are you sure you want to mark all the videos in this course as unwatched?

This will not affect your course history, your reports, or your certificates of completion for this course.

Mark all as unwatched Cancel


You have completed Code Clinic: PHP.

Return to your organization's learning portal to continue training, or close this page.

Become a member to add this course to a playlist

Join today and get unlimited access to the entire library of video courses—and create as many playlists as you like.

Get started

Already a member ?

Become a member to like this course.

Join today and get unlimited access to the entire library of video courses.

Get started

Already a member?

Exercise files

Learn by watching, listening, and doing! Exercise files are the same files the author uses in the course, so you can download them and follow along. Exercise files are available with all Premium memberships. Learn more

Get started

Already a Premium member?

Exercise files video

How to use exercise files.

Ask a question

Thanks for contacting us.
You’ll hear from our Customer Service team within 24 hours.

Please enter the text shown below:

The classic layout automatically defaults to the latest Flash Player.

To choose a different player, hold the cursor over your name at the top right of any lynda.com page and choose Site preferences from the dropdown menu.

Continue to classic layout Stay on new layout
Exercise files

Access exercise files from a button right under the course name.

Mark videos as unwatched

Remove icons showing you already watched videos if you want to start over.

Control your viewing experience

Make the video wide, narrow, full-screen, or pop the player out of the page into its own window.

Interactive transcripts

Click on text in the transcript to jump to that spot in the video. As the video plays, the relevant spot in the transcript will be highlighted.

Learn more, save more. Upgrade today!

Get our Annual Premium Membership at our best savings yet.

Upgrade to our Annual Premium Membership today and get even more value from your lynda.com subscription:

“In a way, I feel like you are rooting for me. Like you are really invested in my experience, and want me to get as much out of these courses as possible this is the best place to start on your journey to learning new material.”— Nadine H.

Thanks for signing up.

We’ll send you a confirmation email shortly.

Sign up and receive emails about lynda.com and our online training library:

Here’s our privacy policy with more details about how we handle your information.

Keep up with news, tips, and latest courses with emails from lynda.com.

Sign up and receive emails about lynda.com and our online training library:

Here’s our privacy policy with more details about how we handle your information.

submit Lightbox submit clicked
Terms and conditions of use

We've updated our terms and conditions (now called terms of service).Go
Review and accept our updated terms of service.