Wave forms on the screen

We saw the explication of the Fourier Transform of a sawtooth wave form. How do you get the sine like wave forms into the pictures on the screen?

In the beginning this was for me as well a kind of puzzle, but a Philips collegue gave me the free Public Domain program "WGNUplot". It is a Windowished version of GNUplot. Click here and you get it as a ZIP-file into your computer.

It is a command oriented program. So you have to type a command, e.g.:


Then you get an overview of the commands.
The only command that I use is:


for example

plot sin(x)

Then a new window appears in which the graph of sine (x).

graph of sine x

WGNUplot adjusts the axes automatically to a sensible length, but this can all be adjusted. You can adjust e.g. the x-axis to stretch the graph in the horizontal direction by:

plot [x=0:7] sin(x)

It will say: x equals 0 to 7.

horizontally streched

In this way you can adjust more parameters, but at a typing error in the command you have to redo typing the command from the beginning. The more complex the command, the more chance for typing errors. I think it's Ok very soon.

Editing as a picture

Everybody knows this of course, but for those few that don't:

How do I get the picture off my screen into a picure editor program?

This one you should just know: type "Alt - Print Scrn".

The active window, in my computer this will say a blue bar at the top, is loaded as a picture into the clip board. Then I open the program "Paint" and select "Edit - Paste". The whole window, including the blue bar, is then available as a picture in Paint and can be stored as .bmp, or whatever. After that you can do with it whatever you want. In this way I exported the pictures above from WGNUplot.

By the way, this trick doesn't work only for WGNUplot. In the same way you can rip pictures out of Word or PDF files as well. Adjust the scaling until the picture fills the screen maximaly and key "Alt - Print Scrn".

Oh yes, WGNUplot can't be terminated using the little cross, it wasn't Windowished that far. In stead of that give the command: