36 MATRIX OPERATIONS

MATROP;

MATROP performs simple matrix manipulations for matrices whose dimensions are those of the one particle basis set. To do so, first required matrices are loaded into memory using the LOAD command. To each matrix an internal name (an arbitrary user defined string) is assigned, by which it is referenced in further commands. After performing operations, the resulting matrices can be saved to a dump record using the SAVE directive. Numbers, e.g. traces or individual matrix elements, can be saved in variables.

code may be one of the following:

LOAD

Loads a matrix from a file

SAVE

Saves a matrix to a file

ADD

Adds matrices

TRACE

Forms the trace of a matrix or of the product of two matrices

MULT

Multiplies two matrices

TRAN

Transforms a matrix

DMO

Transforms density into MO basis

NATORB

Computes natural orbitals

DIAG

Diagonalizes a matrix

OPRD

Forms an outer product of two vectors

DENS

Forms a closed-shell density matrix

FOCK

Computes a closed-shell fock matrix

COUL

Computes a coulomb operator

EXCH

Computes an exchange operator

PRINT

Prints a matrix

PRID

Prints diagonal elements of a matrix

PRIO

Prints orbitals

ELEM

Assigns a matrix element to a variable

READ

Reads a square matrix from input

WRITE

Writes a square matrix from input

SET

Assigns a value to a variable

See the following subsections for explanations.