Archive for the ‘Software’ Category

Saving web page to pdf

Friday, February 12th, 2010

Sometimes it is a good idea to save a web page to a pdf file. For instance, I have just discovered that the quality newspaper Bangkok Post’s online pages are just free for the first 60 days after publication.

wine

The article above discusses how sensors are used in a Thai vineyard. Since my students are hungry for local use of sensors I wanted to save the page as pdf.

There are several ways to do this. The best result I got with PDF Download which is a free Internet service. I dragged an icon called ‘Save Page as PDF’  to my browser’s Bookmarks toolbar (I use Chrome), and when I find a web page to convert, I simply click Save Page as PDF and wait a moment to receive my PDF copy.

I tried PrimoPDF, but when I printed to its driver the result was not identical to the original. There are add-ons for Firefox that saves the entire web page as an image, but since people are more familiar with PDF files, and one may add text to them with CuteFTP, I prefer the pdf solution. It should be noted that the PDF files are really just images, one may not select part of the text.

When will we train students to be more than second hand calculators?

Friday, February 12th, 2010

Maxima is a piece of software that can solve problems symbolically as well as numerically. I downloaded it last week and have played with it for two days. Yesterday I gave it a test my students struggled with earlier this week. Click here to see how it did.

I found lots of help at this forum.

The questions it raises are: Why train the students to solve problems the computer can solve faster and better? It is similar to the question, Why teach students algorithms for square roots or long division when calculators do it better?

The second question I find more interesting: How may students be trained to solve problems the computer is not good at? There is no algorithm for discovering problems, for setting up a model that fits a situation, for interpreting the result the model gives you, for discussing the weaknesses of a model, … When will we train students to be more than second hand calculators?

Macros makes life easier

Saturday, January 16th, 2010

The last two weeks my year 10 ICT students have designed a booking sheet for cinemas. The client (me) had these requirements:

Client’s requirements:
1. Simple to use and learn.
2. Should show all seats for a given performance (rows=23, seats in a row=20, you decide where the passageways are).
3. Use colour code to show seats taken (vacant or free, reserved, taken, price, backup seats)
4. Calculate:
a. # seats taken (total number and in %)
b. total income
New requirements:
1. The price of a seat depends on the location in the cinema and if the customer is a child or an adult.
2. Please protect the cells where one is not supposed to enter information so they will not be overwritten by mistake.
3. Add pie charts to show the various incomes.
4. The prices may change often so make it easy to change them.
5. The program should calculate the cost for each customer and the change they should receive.

1. Simple to use and learn.

2. Should show all seats for a given performance (rows=23, seats in a row=20, you decide where the passageways are).

3. Use colour code to show seats taken (vacant or free, reserved, taken, price, backup seats)

4. Calculate:

a. # seats taken (total number and in %)

b. total income

New requirements:

1. The price of a seat depends on the location in the cinema and if the customer is a child or an adult.

2. Please protect the cells where one is not supposed to enter information so they will not be overwritten by mistake.

3. Add pie charts to show the various incomes.

4. The prices may change often so make it easy to change them.

5. The program should calculate the cost for each customer and the change they should receive.

Today each student or student pair demonstrated (defended) their solution for their peers using the projector on the front computer. Many solutions were excellent, but I could see how macros could make them even more useful.

Macros and programming are not part of the syllabus, but even so on Monday I will tempt their intellectual taste buds with the following.

Sub costandchange

Sheet = thisComponent.Sheets(“Sheet1″)

income = Sheet.getCellRangeByName(“D4″)

oldincome = Sheet.getCellRangeByName(“D5″)

cost = income.value – oldincome.value

received = InputBox (chr(13)+ “The cost is ” + cost + “.” + chr(13) + chr(13)+ “Received:”,”Cinema”)

moneychange = val(received) – val(cost)

msgbox “Change = ” + received + ” – ” + cost + ” = ” + moneychange,,”Cinema”

oldincome.value = income.value

End Sub

The user enters a and c for adults and children and with countif() functions the total income is calculated in D4.

What happens when a new customer buys some tickets? Without a macro you have to type a and c in the cells/seats where they will sit and then type the number of as and cs to find the total cost and later the change they should receive.

With the macro above it is enough to mark the sheet with as and cs. The trick consists in having the total income in both D4 and D5. When as and cs are entered D4 changes, but D5 does not. D4-D5 gives therefore the total cost for the customer.

I found the code tips I needed here.

Writing on a pdf file

Friday, January 15th, 2010

Let’s say you want your students to practice past exam papers that you have in pdf format. Do you print them out and give a copy to each student or is there a way that uses less paper?

With Foxit Reader you can let your students write on the pdf file electronically. The same can not be done with Adobe Reader.

foxit

The text in blue was typed using the Typewriter Tool.

When the file is saved and opened again there are three lines at the top of every page that can be removed if you buy the Foxit Reader Pro Pack. Foxit Reader is free and the added lines don’t bother me for this use.

Video cropping

Sunday, August 30th, 2009

Sometimes I need to show to my students only part of a video I have downloaded. So, how does one crop a video?

Format Factory is a free program that does the job perfectly. Below is an example of a crop I just did. Find the mistake in what is being said by the math expert.

In the UK around 3,400 people die each year in road accidents. That means there is a 1 in 200 chance that anyone of us will die the same way.

Format Factory also converts wav files to mp3. Very convenient as my voice recorder uses wav files while the plugin for playing sound on a WordPress blog requires the mp3 format.

IBM Office for free

Saturday, August 22nd, 2009

ibmoffice

With the introduction of Lotus Symphony age-old rivals, IBM and Microsoft, will again compete with each other. The Lotus Symphony is a free office suite, targeting Microsoft’s golden hen, MS Office. IBM reports that its new office suite offers millions of companies and consumers the chance to save hundreds of dollars on each of their Microsoft Office licenses by providing support for Microsoft Office 2007 with the newest version of Lotus Symphony, IBM’s free of charge productivity software suite. This could translate into millions of dollars in savings at many large companies that are looking for financial relief in the current economy.
The ability to import Microsoft Office 2007 files into Symphony means that Microsoft Office customers can save on licensing costs by switching to Symphony while retaining access to, and easy use of, the contents of their Office files.

With the introduction of Lotus Symphony age-old rivals, IBM and Microsoft, will again compete with each other. The Lotus Symphony is a free office suite, targeting Microsoft’s golden hen, MS Office. IBM reports that its new office suite offers millions of companies and consumers the chance to save hundreds of dollars on each of their Microsoft Office licenses by providing support for Microsoft Office 2007 with the newest version of Lotus Symphony, IBM’s free of charge productivity software suite. This could translate into millions of dollars in savings at many large companies that are looking for financial relief in the current economy.

The ability to import Microsoft Office 2007 files into Symphony means that Microsoft Office customers can save on licensing costs by switching to Symphony while retaining access to, and easy use of, the contents of their Office files. – Read more

IBM Lotus Symphony has a word processor, spreadsheet, presentation, and browser. It does not have a data base program.

However,

The new version of Symphony allows users to drag-and-drop plug-ins, extending its use to other business applications.

By the way:

Symphony is based on an older version of OpenOffice.org, although the code has been heavily modified by IBM.

I downloaded it from here.

Opening MS Word and Excel files

Friday, August 21st, 2009

opendoc

If you want to open a Microsoft Word file do not double-click it in My Computer or right-click and use the Open option. If you do, you may be asked to save it, which is the opposite of what you want.

Either right-click the file and choose Open With and select swriter (see the above image) or open OpenOffice.org Writer and use File – Open to open the file.

openxls

For Microsoft Excel files either right-click, choose Open With and select scalc (see the above image) or open OpenOffice.org Calc and use File – Open to open the file.

Note
The above is the case if the file associations for .doc and .xls files have not been changed to point to OO Writer and OO Calc respectively. If they have, just double-click the files and they will open in the appropriate OO application.

How to change the file associations
In My Computer (i.e. Windows Explorer) click Folder Options on the Tools menu. Click the File Types tab and scroll down to DOC (typing D once and then scroll is another way). Click Change and select swriter.

fileassociations

For xls files, scroll to XLS and select scalc.

Free software

Sunday, June 21st, 2009

dario-fo

In an IGCSE course I teach we have recently switched from pay software to free software.

Task Pay software Free software
Word processing MS Word OO Writer
Spreadsheet MS Excel OO Calc
Database MS Access OO Base
Web authoring MS FrontPage Kompozer
Presentation authoring MS PowerPoint OO Impress
Image manipulation Adobe PhotoShop Irfanview

MS = Microsoft, OO = Open Office.

So far the students have welcomed the change saying for instance that Writer is better than Word and Kompozer better than FrontPage.

As you can see we just do modest image editing so Irfanview is all we need. We may add Gimp and other free software to the list, but this is the beginning.

Why do people/schools prefer to pay for software or use pay software illegally? The main two reasons I believe are ignorance and inertia. They do not know that free alternatives exist, and if they do, they do not see any reason to learn a slightly different software for the task at hand.

Dario Fo is hinting to a third reason.

Tidy fees are the most effective remedy, both for the doctor and the patient.

In other words, if it is free it cannot be good, if it is expensive it has to be good.

Here are just three places where good, free software can be found.

  1. Student’s Guide to Free Software
  2. Reinstall Windows and outfit your system with all freeware programs
  3. 101 Great Free Sites and Downloads You’ve Probably Never Heard Of