1.3.3.0 msplot.plotoptions

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msplot.plotoptions - Function

1.3.3 Set the style of the plot.

Description

Set the style of the plot. This function allows the plot title, axis labels, font, plotting color, plot symbol and many, other aspects of the plot to be set by the user, giving the user much flexibility over the look of their plots.

The various aspects that can be controlled by the user are as follows:

Labels: The title that appears at the top of the plot is controlled by the paramete’r. The label along the x-axis and y-axis are set using the xlabel and ylabel parameters. If no values are not provided by the user then these labels are constructed from the data selected to be plotted.
To control the font size of the labels use the font parameter. The x-axis and y-axis labels are always set to be 2pts. smaller then the title, which is set at the given font size specified.
Size Controls: To control the size of the window, the windowsize, and aspectratio options can be set.
To control the range of points plotted use the plotrange option. This plot option accepts either time strings in the form YYYY/MM/DD/hh:mm:ss or real values.
Data Point Sytles: There are a number of plotoptions for controlling the color and style of the points plotted.
The plotsymbol option set both the color and/or shape of the points plotted. It accepts the same syntax as that used by the pylab plot function. There are six different colors used: ’k’ black, ’r’ed, ’g’reen, ’b’lue, ’c’yan, ’y’ellow, wnd ’w’hite. The plotsymbols include, but are not limited to ’+’, ’o’, ’-’, and ’–’. For a full list see the
matplotlib documentation.
The markersize and linewidth options control how big the plot symbols/lines are.
The multicolor plot option is unique to CASA. It is used to specify whether or not different channels/correlations are plotted in different colors. The colors used can not be set by anyof the plot options. Basically, when plotting the colors are cycled through, changing whenever a different channel or correlation is encountered.
For large measurement sets it may be useful to plot only a portion of the measurment set. The skipnrows allows every nth row to be plotted rather then all of the plots.
Multiple plots: One of the more useful abilities of the CASA plotters is the ability to plot several plot simultaneously, either side-by-side, and/or one on top of the other.
The subplot option determines the number of panels to create, each panel contains a plot of some data. Although the subplot option is a single integer, it is really treated as three separate integers:
- nrows: number of rows of panels,
- ncols: number of columns of panels, and
- panel: the panel number, which panel to plot on.
For example, subplot=132 specifies that there are three panels side-by-side (three columns of panels), and that we are plotting on the second panel. The top, left corner panel is panel number 1, and the panel number increases to the right first, continuing on the next row when the end of a row is reached. The example section shows some examples that create a number of different panel arrangements.
Related to the multi-panel plots is the removeoldpanels option. This option when set to True, the default value, mimics the native matplot behviour, clearing any panels that lie partially or completely under a new panel being plotted. If it is set to False new panels could potentially plot overtop of old panels depending on the subplot values.
In addtions to having plots there is the ability to overplot. The overplot option when set to true will, instead of clearing the panel that is currently being plotted on, plot over what is already there. When overplot is set to true the next plot is plotted over top of what is already there, and if the plotsymbol has not been specified the msplot tool will automatically pick a different color to plot with. An example where this may be useful if plotting different spectral windows separately, but on the same plot.
Related to overplotting is the replacetopplot and showflags option. By default replacetopplot is set to False, but if it is set to True then only the last plot on a panel is replaced. This option comes in handy when a mistake has been made in the last plot. If the showflags option is set to True then the flagged data is plotted. A nice feature is the ability to plot the flagged and unflagged data on the same plot, by doing the same plot with both the overplot and showflags plot turned on. Note that flagged data is always plotted in a magenta color.

Arguments


Inputs
subplot	Three (or four) digits number: first digit for nx, second for ny, the rest for pannel number.
	allowed:	int
	Default:	111
plotsymbol	String specifying the colour to plot in, as well as the symbol to plot. This argument takes the same values as pylab plot command. Some of the valid symbols are: ’o’, ’+’, ...
	allowed:	string
	Default:
plotcolor	String specifying the colour to plot in. This can be one of the predefined pylab colour names. This over-rides the colour specified in plotsymbol.
	allowed:	string
	Default:
multicolor	chan: means different channels in different colours, corr: means different correlations in different colours, both: means different correlations and channels in multicolour none: plot everything the same color.
	allowed:	string
	Default:	none
plotrange	Plot data within the specified range of values will be plotted. The range of values is given as a string in the form [xmin, xmax, ymin, ymax]. For most plots the xmin/max and ymin/max values are expected to be numeric values. However, for time plots, ie. where one or more of the axis is time, the xmin/max and ymin/max are expected to be strings in the from YYYY/MM/DD/hh:mm:ss.
	allowed:	string
	Default:
timeplot	Indicate if the data is to be interpretted as time time values. Valid values are ’o’ff, ’x’-axis, ’y’-axis, ’b’oth axes. .
	allowed:	char
	Default:	’o’
markersize	Specify the size (in pixels) of the markers being plotted. Markers are specified with the plotsymbol option. .
	allowed:	double
	Default:	8.0
linewidth	Occasionally lines, rather then points, are plotted. This option allows the width of the plotted lines to be specified in points (pixels).
	allowed:	double
	Default:	1.0
overplot	To do overplot or not.
	allowed:	bool
	Default:	false
replacetopplot	true : when overplot=false, replace the top-most layer only false : overplot=false always creates a fresh stack of plots.
	allowed:	bool
	Default:	false
removeoldpanels	true : mimic the native matplotlib behaviour of clearing up plots that lie partially or completely underneath a new panel. false : turn this feature off. Explicit mp.clearplot will then be required. This is provided to allow small plots to be inset into larger plot panels.
	allowed:	bool
	Default:	true
skipnrows	Indicates how many points to skip when plotting, ie. it plots every nth point.
	allowed:	int
	Default:	1
averagenrows	Indicates how many rows to average when plotting, ie. average together every n rows.
	allowed:	int
	Default:	1
extendflag	A string contains flag extension code. Possible codes are: ”P” for correlation; ”C” for channel; ”B” for baseline; ”W” for spectral window; and ”T” for time.
	allowed:	string
	Default:
connect	Indicates how to join point with lines when plotsymbol contains ’-’. connect=’none’: points are not connected by lines. connect=’row’ : points are joined along time and baseline and each channel and correlation is a separate line. connect=’chan’: points are joined along channel. Each timestamp or baseline is a separate line. This is to be used in conjunction with ’averagenrows’ or ’skipnrows’ because for a large number of rows, it is inefficient.
	allowed:	string
	Default:	none
showflags	Indicates whether or not to plot flagged and unflagged data. False : plot only unflagged data True : plot only flagged data
	allowed:	bool
	Default:	false
title	string for the title of the plot
	allowed:	string
	Default:
xlabel	string for the X -label of the plot
	allowed:	string
	Default:
ylabel	string for the Y -label of the plot
	allowed:	string
	Default:
fontsize	font size of the labels for the plot
	allowed:	double
	Default:	14.0
windowsize	window size of the plot
	allowed:	double
	Default:	1.0
aspectratio	aspect ratio of the window size of the plot
	allowed:	double
	Default:	1.0

Returns
bool

Example

# open a MS dataset, set the plot options.
# Also set the X and Y axes labels, and the title,
  mp.open( msname=’./data/3C273XC1.ms’);
  labels := [’Amplitude vs UVdist’,’uvdist’,’amplitude’];
  mp.plotoptions( windowsize=5,aspectratio=0.8, fontsize=14.0, \
       xlabel=’uvdist’, ylabel=’amplitude’, title=’Amplitude vs. UVdist’,
       plotsymbol=’g+’ );

# Create 3 panels for plotting, and starting an iterative plot.  Three
# plots will be plotted for each iteration of the plot.
mp.open( ’./data/ngc5921.ms’)
mp.plotoptions( subplot=311 )
mp.vischannel( column=’data’, what=’amp’, iteration=’baseline’ )

# Create 3 panels for plotting, but they are different sizes.
# Two panels at the top, smaller with the array and uvcoverage plots.
# A single wider panel at the bottom (the whole second row) containing
# the uvdistance plot.  The uvdistance plot, plots the corrected data
# overtop of the actual data.
mp.open( ’./data/ngc5921.ms’);
mp.plotoptions( subplot=221 );
mp.array();
mp.plotoptions(subplot=222);
mp.uvcoverage();
mp.plotoptions( subplot=212 );
mp.uvdist();
mp.plotoptions( overplot=1, plotcolor=3);
mp.uvdist(column=’corrected_data’);

# Plot the flagged and unflagged data on the same plot, plotting the
# visibility amplitude vs. the channel.
mp.open(ngc5921PATH);
mp.vischannel();
mp.plotoptions( showflags=1, overplot=1 );
mp.vischannel();

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