### BOXFRAME

Draw a frame and axes on the plot

#### Description:

Draw a frame, axes and tick-marks on a plot. The application has great flexibility in the type of axis labelling that can be produced – it is essentially an interface to the PGPLOT routines PGBOX and PGTBOX.

#### Usage:

boxframe [xopt] [yopt] [xtic] [ytic] [nxsub] [nysub]

#### Parameters:

##### XOPT = _CHAR (Read and Write)
A string that controls the style of the X-axis labelling and tick-marks. It consists of a series of letters, which have the meanings shown below (reproduced from the PGPLOT manual):
• "A" – Draw an axis (the X axis is the horizontal line Y=0, the Y axis is the vertical line X=0).

• "B" – Draw the bottom (X) or left (Y) edge of the frame.

• "C" – Draw the top (X) or right (Y) edge of the frame.

• "G" – Draw a grid of vertical (X) or horizontal (Y) lines.

• "I" – Invert the tick-marks (i.e. draw them outside the viewport instead of inside).

• "L" – Label the axis logarithmically (see below).

• "N" – Write numeric labels in the conventional location below the viewport (X) or to the left of the viewport (Y).

• "P" – Extend (project) major tick-marks outside the box (ignored if option I is specified).

• "M" – Write numeric labels in the unconventional location above the viewport (X) or to the right of the viewport (Y).

• "T" – Draw major tick-marks at the major coordinate interval.

• "S" – Draw minor tick-marks (sub-ticks).

• "V" – Orient numeric labels vertically (this is only applicable to Y – the default is to write Y-axis labels parallel to the axis).

• "1" – Force decimal labelling.

• "2" – Force exponential labelling.

A set of special letters control the plotting of RA and DEC axes.

• "Z" for (DD) HH MM SS.S time labelling

• "H" means superscript numbers with d, h, m, & s symbols

• "D" means superscript numbers with o, ’, & ’’ symbols

• "F" causes the first label (left- or bottom-most) to be omitted. Useful for sub-panels that abut each other. Care is needed because first label carries sign as well.

• "O" means omit leading zeros in numbers $<$ 10 e.g. 3h 3m 1.2s rather than 03h 03m 01.2s Useful to help save space on X-axes. The day field does not use this facility.

Note that to use these features your data values should be in radians (PONGO automatically converts HH:MM:SS.SSS strings to radians, and the DEGTOR command from degrees to radians).

[The global parameter PONGO_XOPT is used. If PONGO_XOPT is not defined, the default value "BCNST" is used.]

##### YOPT = _CHAR (Read and Write)
A string that controls the style of the Y-axis labelling and tick-marks. It consists of a series of letters, as given for the parameter XOPT.

[The global parameter PONGO_YOPT is used. If PONGO_YOPT is not defined, the default value "BCNST" is used.]

##### XTIC = _REAL (Read and Write)
The major tick-mark interval on the X-axis. If XTIC is set to 0.0, PGPLOT makes a sensible choice.

If the value is not specified on the command line, the current value is used. The current value is initially set to 0.0.

##### YTIC = _REAL (Read and Write)
The major tick-mark interval on the Y-axis. If YTIC is set to 0.0, PGPLOT makes a sensible choice.

If the value is not specified on the command line, the current value is used. The current value is initially set to 0.0.

##### NXSUB = _INTEGER (Read and Write)
The number of minor tick-marks between each major tick-mark on the X-axis. If NXSUB is set to 0, PGPLOT makes a sensible choice.

If the value is not specified on the command line, the current value is used. The current value is initially set to 0.

##### NYSUB = _INTEGER (Read and Write)
The number of minor tick-marks between each major tick-mark on the Y-axis. If NYSUB is set to 0, PGPLOT makes a sensible choice.

If the value is not specified on the command line, the current value is used. The current value is initially set to 0.

#### Notes:

• Right Ascension and Declination axes.

It is possible to draw RA and DEC axes using this routine. To do this read in your X and Y data in radians (this is the default if your data are stored in the HH:MM:SS.SSS, DD:MM:SS.SSS formats) and then set the "Z" character in the XOPT and YOPT parameters. A good combination of options are:

XOPT=’BCNSTZHG’ YOPT=’BCNSTZDG’

For more about this (in particular how the interval options are set) see the PGPLOT documentation about PGTBOX. Note that the "Y" option is always set and that the Y axis values are converted into pseudo arc seconds.