Reading Data into the Dataplot GUI
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Typically, the first issue in using the Dataplot GUI is
"How do I get my data into the GUI"?
If your initial interest is in simply experimenting with
the Dataplot GUI, then you can load one of the built-in
data sets. Select the "Files/Data" menu. There will be
a section titled "Dataplot datasets". Select the
"Open (READ/LOAD)" menu. This menu divides the available
data sets into a number of common categoreis. Select
a category of interest and then select one of the data
sets. The Dataplot GUI will then issue the appropriate
Dataplot commands to read the file.
You have a few options for reading your own data into
the Dataplot GUI.
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Issues Regarding Data Files in Dataplot
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The following are some issues regarding files in
Dataplot.
- The length of file names, including the path (or
directory) name, is limited to 80 characters.
- If your file name contains spaces or hyphens, then
you need to enclose the file name in double
quotes ("). The ability to enclose file names
in quotes was introduced in the 7/2002 version of
Dataplot.
- Currently, Dataplot expects ASCII files.
In general, Dataplot assumes a rectangular
layout with columns being variables and rows
being observations. Also, Dataplot only
reads numeric data (enter HELP READ ROW
LABELS for details on one exception).
Dataplot does provide commands for skipping
header lines and for restricting which
rows and columns are read.
Dataplot does support format specification.
This can significantly speed up reading
larger data files and it can allow you to
skip over alphabetic variables. However,
this does require that your data be in
a consistent format.
Dataplot currently does not read Excel (or
other spreadsheet) formats. We are
investigating adding the capability for this,
but for now you need to write an ASCII
file (using either space or command delimited
text files) from Excel.
- Although the data spreadsheet window is convenient,
it can impose significant overhead. We recommend
that you click the "No Update" button on the spreadsheet
before reading large data files. The definition of
large will depend somewhat on how fast your computer
is, but a good starting point is check the "No Update"
if you anticipate reading more than 1,000 rows of data.
This issue is discussed in detail in the
Performance Issues web
page.
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Date created: 6/5/2001
Last updated: 9/20/2002
Please email comments on this WWW page to
sedwww@cam.nist.gov.
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