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Last modified: December 2013

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AHELP for CIAO 4.9 ChIPS v1


Context: lines


Moves the line to a new location.


move_line(xval, yval)
move_line(xval, yval, mode)
move_line(id, xval, yval)
move_line(id, xval, yval, mode)


The function arguments.

Argument Description
xval, yval The x and y coordinates to move. The mode parameter determines whether these are relative or absolute. Unless explicitly specified by the coord_sys field of the optional ChipsId argument, the coordinate system used to create the object is used.
mode The position is in absolute coordinates (mode=0) or relative (mode=1). The default is absolute.
id A ChipsId structure identifying the item.

The move_line command moves the line to a new position. The new location may be specified as an absolute position (default) or as relative offsets from the original location. When the "mode" parameter is set to absolute (0), (xval,yval) will be the origin of moved line. The origin of a line is the first point specified when creating the line.

The following coordinate systems may be used to move a line: PIXEL, WINDOW_NORM, FRAME_NORM, PLOT_NORM, or DATA. The system is specified by setting the coord_sys field of the optional ChipsId structure which may be passed into the move_line routine. If a ChipsId is not provided, the default coordinate system of the line is used.

When a line is moved, it remains in its original coordinate system regardless of what coordinate system was used for the move. The move command translates the specified values to the coordinate system that the line is in before applying them to the line. This means that lines that are originally placed in normalized coordinates and get relocated using data coordinates will not be clipped if they land outside the visible data range. Conversely, lines in data coordinates which are moved using normalized coordinates to beyond the plot area will be clipped.

This command is equivalent to calling the move command with 'chips_line' specified as the object.

Example 1

chips> move_line(.5,.5)

Move the current line to (0.5, 0.5) in the coordinate system used to create it.

Example 2

chips> clear()
chips> add_curve([1,2,3], [4,5,6])
chips> add_line(0.05, 0.95, 0.15, 0.95, ['coordsys', PLOT_NORM])
chips> move_line(0.8, 0.1)

The line is created in the top-left corner of the plot, then moved so that it is in the bottom-right corner.

Example 3

chips> id = ChipsId()
chips> id.coord_sys = PIXEL
chips> move_line(id, -20, 0, 1)

For a line specified in data coordinates, adjust the position by 20 pixels to the left in the x direction. Do not move it in the y direction.

Example 4

chips> id = ChipsId()
chips> id.line = 'all'
chips> id.coord_sys = DATA
chips> move_line(id, 40, 10, 1)

Shift all lines by the same distance in data coordinates.


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

See Also

add_hline, add_line, add_vline, current_line, delete_line, display_line, get_line, hide_line, set_line, shuffle_line

Last modified: December 2013
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