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Last modified: December 2006

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

Synopsis

Sets the ranges to be displayed in the axes.

Syntax

chips> [D #] LIMITS [<coor>] {<min> | AUTO | *} {<max> | AUTO | *}
chips> [D #] LIMITS {<xmin> | AUTO | *} {<xmax> | AUTO | *} \
{<ymin> | AUTO | *} {<ymax> | AUTO | *} \
[{<zmin> | AUTO | *} {<zmax> | AUTO | *}]

Description

Argument: <coor>
Description: axis coordinates
Options: X, Y  
Default: X 
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: <min>
Description: lower limit for axis range
Options: real numbers
Default: AUTO
Argument: <max>
Description: upper limit for axis range
Options: real numbers
Default: AUTO
Argument: <xmin>
Description: lower limit for X-axis range
Options: real numbers
Default: AUTO
Argument: <xmax>
Description: upper limit for X-axis range
Options: real numbers
Default: AUTO
Argument: <ymin>
Description: lower limit for Y-axis range
Options: real numbers
Default: AUTO
Argument: <ymax>
Description: upper limit for Y-axis range
Options: real numbers
Default: AUTO
Argument: <zmin>
Description: lower limit for Z-axis range
Options: real numbers
Default: AUTO
Argument: <zmax>
Description: upper limit for Z-axis range
Options: real numbers
Default: AUTO

The limit specifications come in pairs, with the first being the lower limit. A limit specification may be a number, an asterisk (*), or the argument AUTO. A '*' indicates no change in the current limit, while AUTO allows the underlying plotting package to select the limit value.

ChIPS converts double-precision numbers to floating-point values before plotting them, which can cause problems for values that are either too large or too small. The allowed range is approximately 1e-38 to 3e38 (for both positive and negative values).

The limits of the x and y axes in a contour plot cannot be modified in the current version of ChIPS.

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

Example 1

chips> CURVE data/example.dat
chips> LIMITS X 5.0 15.0
chips> LIMITS Y 2.0 4.0
chips> LIMITS X AUTO AUTO
chips> LIMITS Y AUTO AUTO

The first two LIMITS commands change the displayed ranges of the X and Y axes, respectively. The final two commands instruct the plotting package to determine the X and Y limits. The two pairs of commands (4 lines) may be reduced to two lines:

chips> LIMITS 5.0 15.0 2.0 4.0
chips> LIMITS AUTO AUTO AUTO AUTO

Example 2

chips> LIMITS * 15.0 * 4.5

This command preserves the minimum value of each axis, but changes the maximum of the X-axis to 15.0 and of the Y-axis to 4.5.

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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