Tuesday, September 3, 2013

Lesson 13 - Desktop

The main challenge this time was to keep the smaller girl entertained while practising mad skills with the other. Fortunately there was a certain "makkarapeli", i.e. a monster-feeding game on the iPad...

She remembered the file name from the last time and that we can use vim to edit it. She also typed both correctly. The challenge is still to remember to type a space between the program and the file name. Anyway, we added a new word to our pää file and had the computer recite the file again. All this went quite smoothly and quickly this time.

Then we discussed directories for a while and moved the pää file to a directory called "Desktop". She remembered the word move from the last time and that the program is actualy spelled mv. It was fun to discover that the pää file could now be found on the computer's desktop. We even opened the file in Textedit, but she was not very enthusiastic about doing any editing to the file this time. So we decided that it was enough.

But it wasn't. With some help, she googled for pictures of pricesses, then saved a photo of a cake on the Desktop. We used "ls Desktop" to list the files on the desktop on the command-line. Then discussed the hard disc and directories again.

Then to Turtle Roy, where she demanded that we must make a circle this time. While I was making oatmeal and pampering the hysterically crying smaller girl, my vim-girl learned how to type square brackets and managed to produce the following program (I practically dictated this one):

    s [lt 10, fd 10]

Here s is a function that runs the listed actions sequentially, i.e. turns left 10 degrees and then proceeds 10 pixels. Then she repeated this a few times and declared that she can see the angles in the output, hence it won't form a circle. So I taught her how to edit the command line so that it will proceed just 1 pixel and turn 1 degree. Then she repeated that one for some time and was convinced that a circle would appear in the long run. 

The little one was now playing makkarapeli and not yelling or bashing at us or the computer, so we were now able to discuss programming a bit. The thing was that repeating the steps manually would be tiresome and we should use a function repeat to repeat the step 360 times for a full circle. I demonstrated this and we were both happy with the result. Next time she'll do it herself.

Afterwards, while eating oatmeal, she proclaimed cheerfully:

    "I can code!"

Then with a smaller voice: "Not as well as daddy though". Practice makes perfect.


  1. How do you deal with the fact that commands are in English versus Finnish?

  2. It has actually seemed to be a good thing that the command-line commands as well as the whole OS is in English. She gets to learn English on the way. She also happens to have started in an English kinderkarten a few months ago, so there's some synergy. She finds out that the new language she learns there is actually useful with computers too. And there's a lot of other "auxiliary skills" she's been learning while working with computers, including reading/writing/typing, math and geometry.