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prows plot



prows -- plot average of image rows


prows image row1 row2


Input image containing rows to be plotted.
First row to average.
Last row to average.
wcs = "logical"
The world coordinate system (wcs ) to be used for axis labeling when input is f rom images. The following standard world systems are predefined.
Logical coordinates are image pixel coordinates relative to the image currently being displayed.
The physical coordinate system is invariant with respect to linear transformations of the physical image matrix. For example, if the reference image was created by extracting a section of another image, the physical coordinates of an object in the reference image will be the pixel coordinates of the same object in the original image. The physical coordinate system thus provides a consistent coordinate system (a given object always has the same coordinates) for all images, regardless of whether any user world coordinate systems have been defined.
The "world" coordinate system is the current default WCS . The default world system is the system named by the environment variable defwcs if defined in the user environment and present in the reference image WCS description, else it is the first user WCS defined for the image (if any), else physical coordinates are returned.
wx1=0., wx2=0., wy1=0., wy2=0.
The range of window (user) coordinates to be included in the plot. If the range of values in x or y = 0, the plot is automatically scaled from the minimum to maximum data values along the degenerate axis.
vx1=0., vx2=0., vy1=0., vy2=0.
NDC coordinates (0-1) of the plotting device viewport. If not set by the user, a suitable viewport which allows sufficient room for all labels is used.
pointmode = no
Plot individual points instead of a continuous line?
If pointmode = yes, the marker drawn at each point is set with this parameter. Acceptable choices are "point", "box", "plus", "cross" and "circle".
szmarker = 0.005
The size of the marker drawn when pointmode = yes.
logx = no, logy = no
Draw the x or y axis in log units, versus linear?
xlabel = "wcslabel", ylabel = ""
Label for the X-axis or Y-axis. if xlabel = "wcslabel" the world coordinate system label in the image, if defined, is used.
xformat = "wcsformat"
The numerical format for the coordinate labels. The values may be "" (an empty string), %f for decimal format, %h and %H for xx:xx:xx format, and %m and %M for xx:xx.x format. The upper case %H and %M convert degrees to hours. Some images have a recommended x coordinate format defined as a WCS attribute. If the xformat value is "wcsformat" the WCS attribute format will be used. Any other value will override the image attribute.
title = "imtitle"
Title for plot. If not changed from the default, the title string from the image header, appended with the rows being plotted, is used.
majrx=5, minrx=5, majry=5, minry=5
The number of major and minor divisions along the x or y axis.
round = no
Round axes up to nice values?
fill = yes
Fill the plotting viewport regardless of the device aspect ratio?
append = no
Append to an existing plot?
Output device.


Plot the average of specified rows from an image. The user can control the plot size and placement, the scaling and labeling of axes. Rows can be plotted as a continuous line or individual points with a specified marker.

If append is enabled, previous values for box , fill , round , the plotting viewport (vx1 , vx2 , vy1 , vy2 ), and the plotting window (wx1 , wx2 , wy1 , wy2 ) are used.

If the plotting viewport was not set by the user, prows automatically sets a viewport centered on the device. The default value of fill = yes means the plot spans equal amounts of NDC space in x and y. Setting the value of fill to "no" means the viewport will be adjusted so that the square plot will span equal physical lengths in x and y when plotted. That is, when fill = no , a unity aspect ratio is enforced, and plots appear square regardless of the device aspect ratio. On devices with non square full device viewports (e.g., the vt640), a plot drawn by prows appears extended in the x direction unless fill = no.


1. Plot rows 128 through 150 of image crab.5009 with default parameters:

cl> prows crab.5009 128 150

2. Overplot rows 128 through 150 of using circles to mark the added points:

cl> prows 128 150 append+ pointmode+ marker=circle

3. Annotate the axes of the plot:

cl> prows crab.5009 64 128 xlabel="Column Number" ylabel=Intensity


To plot the average of 20 rows from a 512 square image, prows takes about 1.5 cp seconds.



prow, pcol, pcols

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