In addition to the FITS source list, the user may supply further source particulars directly via the command line. This is controlled via the boolean addusersources. Information on the RA and Dec of the sources as well as their desired (alphanumeric) labels and colours is supplied via the list parameters userras, userdecs, userlabels and usercolours. Naturally, the order in which the information is supplied to each of these four parameters must be the same, and they must have the same number of list members.
To illustrate, the addition to the implot command line of
addusersources=yes userras='35.43 35.90' userdecs='-4.76 -4.71' userlabels='SNR_8 RR-32' usercolours='1 2'causes implot to add two extra source annotations to the plot at the RA/Dec pairs specified. User-added sources are denoted by crosses rather than circles, so the user additions here will appear as a white cross at RA=35.43, dec=-4.76 with (white) label SNR_8, and a red cross at RA=35.90, dec=-4.71 with (red) label RR-32.
