
* catdcd *
* Written by Justin Gullingsrud, based on DCD I/O code from VMD

* Features *
- catdcd functions much like the Unix "cat" command: it concatenates DCD files
into a single DCD file.  The syntax is
	catdcd <outputfile> <inputfile1> <inputfile2> ...

You can also use catdcd to write only selected atoms to the final DCD file.
The syntax in that case is
	catdcd <outputfile> -i <indexfile> <inputfile1> <inputfile2> ...

The combination "-i <indexfile>" must come right after the output file.  
<indexfile> should contain the (zero-based) indices of the atoms in the
dcd files whose coordinates are to appear in the output file.  The indices
should be plain text, separated by whitespace.

- The input files may be any combination of charmm or xplor format, and big-
or little-endianness.  However, they must all have the same number of atoms.

- The code uses only standard C library commands and thus be portable to 
pretty much anywhere, including non-Unix platforms.
 
- Note that DCD's with fixed atoms will not work properly.

* Installation * 
Unpack the distribution package.  A directory named catdcd will be created.
Enter that directory and type "make".  To use a different compiler or compile
flags, edit the first three definitions in the Makefile.

