47.21 Reading a matrix from the input file (READ)

READ,name,[[TYPE=]type],[[SUBTYPE=]subtype],[[SYM=]symmetry], [FILE=file]
{ values }

Reads a square matrix (symmetry 1) from input or an ASCII file. The values can be in free format, but their total number must be correct. Comment lines starting with '#', '*', or '!' are skipped. If the data are given in input, the data block must be enclosed either by curley brackets or the first linbe must be BEGIN_DATA and the last line END_DATA. If a filename is specified as option, the data are read from this file. In this case, the BEGIN_DATA, END_DATA lines in the file are optional, and no data block must follow.

For compatibility with older versions, the data can also be included in the input using the INCLUDE command (see section 3.1). In this case, the include file must contain the BEGIN_DATA and END_DATA lines (this is autopmatically the case if the file has been written using the MATROP,WRITE directive).

type is a string which can be used to assign a matrix type. If appropriate, this should be any of the ones used in the LOAD command. In addition, SUBTYPE can be specified if necessary. This describes, e.g., the type of orbitals or density matrices (e.g., for natural orbitals TYPE=ORB and SUBTYPE=NATURAL). The matrix symmetry needs to be given only if it is not equal to 1.