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Last modified: December 2006

URL: http://cxc.harvard.edu/ciao3.4/log.html
Hardcopy (PDF): A4 | Letter
AHELP for CIAO 3.4 log Context: chips

Synopsis

Changes one or more axes to logarithmic scale.

Syntax

chips> [D #] LOG [<coor>]

Description

Argument: D #
Description: drawing area number designation
Options: integer numbers
Default: current drawing area

See the D command for more information about this argument.

Argument: <coor>
Description: axis coordinates
Options: X, Y  
Default: both X and Y

Note that a warning is returned when a LOG command is issued for data containing negative or zero values: "Warning: negative and zero values ignored in log scale".

The command LINEAR is used to return an axis to linear scale.

CIAO allows some plot attributes to be changed using the ChIPS state object and resource file. See "ahelp chips" for further details.

Example

chips> CURVE data/example.dat
chips> LOG X
chips> LOG
chips> LINEAR

The data is plotted, then the X-axis is changed to logarithmic scale. The second LOG command changes both the X and Y axes to logarithmic scale, and the LINEAR command returns both axes to linear scale.

Bugs

See the bugs page for ChIPS on the CIAO website for an up-to-date listing of known bugs.

Hardcopy (PDF): A4 | Letter
Last modified: December 2006



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