Examples of -difffluxtomag command

Syntax:

-difffluxtomag mag_constant offset ["magcolumn" col]

Example 1.

$ echo "EXAMPLES/1 10.085" | \
  ./vartools -l - -header \
             -difffluxtomag 25.0 0.0 -rms

#Name Mean_Mag_1 RMS_1 Expected_RMS_1 Npoints_1
EXAMPLES/1  10.08501   0.00000   0.00000  3122

Convert a light curve from ISIS differential photometry flux format to magnitudes. The input list is piped via stdin and contains the light curve filename in column 1 and the star's reference magnitude (10.085) in column 2. Since magcolumn is not specified, the reference magnitude is read from the next available column (column 2) by default. The zero-point magnitude constant is 25.0 (i.e., a source with a flux of 1 ADU has magnitude 25.0) and the offset is 0.0. The -rms command outputs statistics for the converted light curve. Note that in practice the light curve should contain ISIS differential flux values; EXAMPLES/1 is in magnitude format and is used here only to illustrate the command syntax.

Example 2.

$ echo "EXAMPLES/1 10.085" | \
  ./vartools -l - -header \
             -difffluxtomag 25.0 0.0 magcolumn 2 -rms

#Name Mean_Mag_1 RMS_1 Expected_RMS_1 Npoints_1
EXAMPLES/1  10.08501   0.00000   0.00000  3122

Same as Example 1, but explicitly specifying that the star's reference magnitude is in column 2 of the input list using the magcolumn keyword.