3.2.2. - File format; specifying columns
Get data modes 2, 3, 4, 5, 11 and 12 take data from ASCII files. Modes 1 and 8, which read from the keyboard, obey similar rules.
C-PLOT interprets columns as sequences of characters (not necessarily numbers) separated by any number of space or tab characters. For get-data modes 1, 2, 4 and 11, the default column ordering puts x and y values in the first two columns. For 2D plotting the next columns are assigned to x error bars (represented as r), y error bars (represented as s) and pen control (represented by p), but these columns will be scanned for values only if the respective features have been turned on using the error-bar or line-control commands. (See
eb below and
lc in Chapter 5.)
In 3D mode,
the first three columns are for
x,
y
and
z
data.
Optional columns for
z
error bars (also represented as
s)
and pen-control information follow.
Under get-data modes 3, 5, 8 and 12, you specify the columns from which C-PLOT will take data values. If you enter a value of 0 for the x, y or z column, the current value for each point will be retained. If you enter a negative value for the columns for x, y, z or all three, the index number of the point (starting at 0) will be assigned rather than a number from the file. There may be up to 2,048 characters on an input line; any additional characters are discarded. There is no limit on the number of columns as long as the data is within the first 2,048 characters of the input line.