Introduction to Igor

Why use Igor...as opposed to Excel?

Igor is a data analysis software package designed for scientist. Although Excel does a great job plotting most data, it does a poor job of preparing data/graph/plots to be used in manuscripts, posters, or powerpoint presentations. Excel also treats data as individual data values where as Igor treats data as arrays (or "wave"). For example, when you collect an X-Y data set of 1000 data points (very common in science) it is more logical to work with the x-array and y-array, as in plotting X vs Y. There is often no reason to see a table with 1000 numbers in it.

Igor does have a relatively steep learning curve, but these basic into activities will serve you well in mastering Igor.

Entering data into an Igor file

All Igor files have data. This data can be manually entered (less common) or imported (more common).

Manually entering Data

- Data is stored in the form of a "wave", so the first step in manually entering data is to "make a wave" where the data can be entered. From the Data-tab choose "Make Waves..." This will open a window where you can name your wave(s) and indicate how many data points will be in the wave.

- Make a wave called --> wave_01 and wave_02 with 6 rows and then display the contents of those waves (currently empty) in a table by choosing the Window-tab and selecting "New Table..." You will be prompted to select the waves that you wish to add to the table (hold down the shift-key to select more than one wave). The resulting table/waves will be zeros...click in the individual cells and enter the following data values:

• wave_01 --> 1, 2, 3, 4, 5, 6
• wave_02 --> 10, 20, 30, 40, 50, 60

Importing Data

Before beginning, you need some data -->:- Click here...and then "save as" Make sure you know where you stored the files.

- From the Data-tab choose "Load Waves...", then "Load General Text..." This will open a window where you can select a file on your computer to import.

• include axes labels x = time; y = number

c: Import "Load waves":

- Click here...and then "save as"

- Note that this file has header information.

• include axes labels x = Magnetic Field (Gauss); y = Intensity

d) Make a new Layout and add both graphs...add you name...then print