4.3.27. eigenvec.dat

When OutputEigenVec=1 in a CalcMod file, the eigenvectors calculated by the Lanczos method are outputted. When InputEigenVec=1 in a CalcMod file, eigenvectors are inputted by this outputted file. The file format is of the binary type.

File name

• ##_eigenvec_&&_rank_$$.dat

## indicates [string02] in a ModPara file, && is the number of eigenvalues, and $$ is a number of rank.

File format

This file is written through the following source code (a little different fron the actual HPhi++ source).

fp = fopen("zvo_eigenvec_0_rank_0.dat", "wb");
fwrite(&number_of_interations, sizeof(int), 1,fp);
fwrite(&local_size, sizeof(unsigned long int),1,fp);
fwrite(&eigen_vector[0], sizeof(complex double),local_size+1, fp);
fclose(fp);

where number_of_interations is the number of iterations, local_size is the size of eigenvector (if MPI is used, it differs from the dimension of the Hilbert space), eigen_vector is the (complex) eigenvector.

Note: The fist component of eigen_vector (eigen_vector[0]) is not used for calculation.