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Last modified: 28 November 2012

URL: http://cxc.harvard.edu/chips/bugs/axes.html

Bugs: axes


Table of Contents

Bugs


Bugs

Axis label angles are not part of default attributes

The following does not work:

add_axis (Y_AXIS, 0,0,10,"y.label=FOO label.angle=45")

The axis label is not rotated 45degrees. It must be rotated separately with a call to >set_axis("ay1", "label.angle=45").

Undoing a set_axis call may not work correctly when used on an axis that is drawn with a logarithmic scale

The bug depends on what attributes are changed.

chips-1> x = 10**np.linspace(-1,1,20)
chips-2> y = x**2
chips-3> add_curve(x, y)
chips-4> get_plot_range()
         [-0.395, 10.495, -4.9895000000000005, 104.9995]
chips-5> log_scale(X_AXIS)
chips-6> get_plot_range()
         [0.07943282347242815, 12.589254117941673, -4.9895000000000005, 104.9995]
chips-7> set_axis(["pad", 0])
chips-8> get_plot_range()
         [0.1, 10.0, 0.010000000000000002, 100.0]
chips-9> undo()
chips-10> get_plot_range()
          [0.1, 10.0, 0.010000000000000002, 100.0]

The plot and ranges have not been reverted to the state at line chips-6. Calling log_scale on the axis again fixes up the plot:

chips-11> log_scale(X_AXIS)
chips-12> get_plot_range()
          [0.07943282347242815, 12.589254117941673, -4.9895000000000005, 104.9995]

Axes do not wrap around 360 degrees when using RA/Dec coordinates.

As a result, plotted contours or image may appear incorrect, and adjusting limits may not work correctly.

Setting the axis label

If the an axis label is set using the axis.x.label or axis.y.label attributes of an add_<object> call then the string must be surrounded by double quotes if it contains spaces; for example:

chips> add_curve(time, zoff, ['axis.y.label', '"Z offset (arcsec)"'])

Sexagesimal formats may produce invalid axis labels when the range is small

Axis labels displayed in sexagesimal format - e.g. tickformat=%ra - may be invalid when the axis range is small (several arcseconds) and a WCS transform is not attached to the axes.

This only affects plots with linear axes. It does not occur if the plot was created by either add_image or add_contour, or a WCS transform object was used when calling add_axis.

Only tangent-plane projections are supported

If you display an image that contains an unsupported axis transformation (e.g. RA--SIN,DEC--SIN), it looks like the projection is supported - i.e. the axes are drawn - but they are not correct.


Bugs fixed in CIAO 4.5

The following is a list of bugs that were fixed in the CIAO 4.5 software release.

Binding axes with arbitrary ticks fails to refresh the plot.

In the following example, after line 6, the plot axes are not correctly displayed. Changing the ticks to nice and then back to arbitrary causes the plot to correctly refresh.

chips-1> split(2)
chips-2> add_curve([1,2,3], [1,2,3])
chips-3> set_arbitrary_tick_positions('ax1', [1,2,3], ["foo", "bar", "baz"])
chips-4> current_plot('plot2')
chips-5> add_curve([1,2,3], [1,2,3])
chips-6> bind_axes('plot1', 'ax1', 'plot2', 'ax1')
chips-7> set_axis("ax1","majortick.mode=nice")
chips-8> set_axis("ax1","majortick.mode=arbitrary") 

Arbitrary ticks cannot be set to empty strings.

In CIAO 4.4, set_arbitrary_tick_positions could not be used to set the first major tick mark to be empty. This is fixed in CIAO 4.5, as shown in the Adjusting axis labels gallery example.


Last modified: 28 November 2012
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