Cat'', which does to SEPlib files something like what ``
cat'' does to ASCII files.
Cat Txx.H Txy.H Txz.H > Three.HNow make a wiggle plot of this new file by doing:
Wiggle < Three.H | Tube
Pretty snazzy, eh? Tube realizes that there are three different panels, so it shows all three of them.
Look at the history file
Three.H to see how history ``accumulated''
in this example. In general, each successive SEPlib program writes more
information onto the end of the history file. (
Cat is a bit of
a special case, since it is always called with multiple input files
and doesn't use redirected input.
Most SEPlib programs
read a file from standard input and write a file to standard
output. The SEPlib input and output subroutines shared by all
such ``standard'' programs begin by automatically copying the input header
straight across to the output unchanged. Anything the running program
wants to add to the history then gets appended.
Cat has to do the copying ``by hand'', so its output looks a little
Note that lines setting parameters
such as ``
n3=1'' can occur multiple times in one history file,
as various programs set old parameters to new values.
The last-defined value is the only valid one, because it
is the ``most recent'' and corresponds to the current data.
You might be thinking now that using ``
to examine history files to find the dimensions
of the associated data file can get confusing and tedious
if the history is long and complex.
A quick way to examine the dimensions and properties of a SEPlib file
is to use the command ``
In Three.Hgives the salient features of the dataset
Three.H: in="/usr/local/sep/scr/joe/Three.H@" expands to in="/usr/local/sep/scr/joe/Three.H@" esize=4 n1=1024 n2=20 n3=3 61440 elem 245760 bytes d1=.002 d2=.1 d3=1 o1=0 o2=.1 o3=0 label1=Time, seconds label2=Offset, kilometersNote that ``
Three.H'' is a three-dimensional block of data, with
When you are done with
Three.H, delete it by doing
Rm Three.HThis will delete both the history file and its associated binary data file. If you slip and accidentally use
rminstead, the binary data file will remain behind uselessly cluttering up your data directory, possibly forever if nothing ever looks for junk files to clean up there.
Warning: the default behavior of both
is to go ahead and delete without confirmation.
You probably have
rm -i (you may have forgotten doing it),
but you probably don't have