Imagine the Universe!
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Tools covered in this section
* List Data
*Plot Light Curve
*Search via Fold
*Epoch Fold

List Data

The first tool in this suite allows you to take a look at the raw data, without the header information. This function can yield information needed to use other analysis tools. From the data directory, select the data file gx301-2.lc. Then, in the available tools window on the left, select List Data in the XRONOS file and click on the "run" button. In the parameter box, the correct data directory and file name should be filled in (type it manually if it is not). Click on the "run" button to execute the program. When it is finished paging through the data, you can scroll up to the top to see what each column contains.

Exercise T1

  • How many data points are contained in the data file?
  • If you were to plot this data by hand, and you plotted one data point per second, how long would it take you to complete the plot?
  • What is the time separation (approximate or average) of the data points? (Remember that you can find the variable names by running the Collumn List tool)

You can see from this data dump how hard it would be to do any analysis by hand, using a calculator and typing in the numbers, for example. Luckily for us there are many tools available for manipulating such large data sets!

Imagine the Universe is a service of the High Energy Astrophysics Science Archive Research Center (HEASARC), Dr. Nicholas White (Director), within the Laboratory for High Energy Astrophysics at NASA's Goddard Space Flight Center.

The Imagine Team
Project Leader: Dr. Jim Lochner
All material on this site has been created and updated between 1997-2004.

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