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diff --git a/ds9/doc/ref/grid.html b/ds9/doc/ref/grid.html new file mode 100644 index 0000000..ed772cc --- /dev/null +++ b/ds9/doc/ref/grid.html @@ -0,0 +1,90 @@ +<!DOCTYPE doctype PUBLIC "-//w3c//dtd html 4.0 transitional//en"> +<html> + <head> + <meta http-equiv="Content-Type" content="text/html; + charset=ISO-8859-1"> + <meta name="GENERATOR" content="Mozilla/4.78 [en] (X11; U; Linux + 2.4.7-10 i686) [Netscape]"> + <title>Coordinate Grids</title> + </head> + <body alink="#ff0000" bgcolor="#ffffff" link="#0000ee" text="#000000" + vlink="#551a8b"> + <h3><img alt="" src="../sun.gif" align="middle" height="98" + width="100"> Coordinate Grids</h3> + <blockquote> + <p>DS9 can create and display coordinate grids as an overlay on an + image. The Display Coordinate Grid Menu is used to display + grids. A coordinate grid is composed of Grid Lines, Axes, + Border, and Title. Axes include tick marks, title, and numbers. + The appearance of the coordinate grid is specified by + parameters. These parameters may be configured via the + Coordinate Grid Parameters dialog box. In addition to the axes + titles and the grid title, the following menus are available. </p> + <p><b><a name="Format"></a>Numeric Formats</b></p> + <p>The user may specify custom numeric formats for either axes. + The format specification can be empty (default) or a print + function, based on the selected coordinate system:<br> + </p> + <blockquote> <tt>image</tt><br> + <tt>physical</tt><br> + <tt>detector</tt><br> + <tt>amplifier</tt><br> + <tt>wcs linear</tt><br> + <tt>wcs equatorial</tt><br> + </blockquote> + <p>The format specification string to be passed to the C "printf" + function (e.g. "%%1.7G") in order to format a single coordinate + value.</p> + <p>The Format string supplied should contain one or more of the + following characters. These may occur in any order, but the + following is recommended for clarity:</p> + <blockquote> "": Indicates that a plus sign should be prefixed to + positive values. By default, no plus sign is used.<br> + "z": Indicates that leading zeros should be prefixed to the + value so that the first field is of constant width, as would be + required in a fixed-width table (leading zeros are always + prefixed to any fields that follow). By default, no leading + zeros are added.<br> + "i": Use the standard ISO field separator (a colon) between + fields. This is the default behaviour.<br> + "b": Use a blank to separate fields.<br> + "l": Use a letter ("h"/"d", "m" or "s" as appropriate) to + separate fields.<br> + "g": Use a letter and symbols to separate fields ("h"/"d", "m" + or "s", etc, as appropriate), but include escape sequences in + the formatted value so that the Plot class will draw the + separators as small super-scripts.<br> + "d": Include a degrees field. Expressing the angle purely in + degrees is also the default if none of "h", "m", "s" or "t" are + given.<br> + "h": Express the angle as a time and include an hours field + (where 24 hours correspond to 360 degrees). Expressing the angle + purely in hours is also the default if "t" is given without + either "m" or "s".<br> + "m": Include a minutes field. By default this is not included.<br> + "s": Include a seconds field. By default this is not included. + This request is ignored if "d" or "h" is given, unless a minutes + field is also included.<br> + "t": Express the angle as a time (where 24 hours correspond to + 360 degrees). This option is ignored if either "d" or "h" is + given and is intended for use where the value is to be expressed + purely in minutes and/or seconds of time (with no hours field). + If "t" is given without "d", "h", "m" or "s" being present, then + it is equivalent to "h".<br> + ".": Indicates that decimal places are to be given for the final + field in the formatted string (whichever field this is). The "." + should be followed immediately by an unsigned integer which + gives the number of decimal places required, or by an asterisk. + If an asterisk is supplied, a default number of decimal places + is used which is based on the value of the Digits attribute.<br> + </blockquote> + <p>All of the above format specifiers are case-insensitive. If + several characters make conflicting requests (e.g. if both "i" + and "b" appear), then the character occurring last takes + precedence, except that "d" and "h" always override "t".</p> + <p>The default formats are <tt>d.3</tt> for degrees and <tt>hms.1</tt> + / <tt>dms.1</tt> / <tt>ldms.1</tt> for sexagesimal.<br> + </p> + </blockquote> + </body> +</html> |