Interface design

The library operates with two fundamental objects, model/data vectors and operators. All vectors are SEP files stored on a disk, and are represented inside the library as SEP file tags Nichols et al. (1994). The operators are function calls that must conform with the following interface:

function oc_operator(adj,add, x_,yy_, op1 ...op9) result(stat)

where

• stat[logical] is a success flag
• adj [logical] is a flag signaling the adjoint operator
• add [logical] is a flag specifying if the result of the operator is to be added to the output
• x_ [char(len=128)] is a file tag in the model space
• yy_ [char(len=128)] is a file tag in the data space
• op1 ...op9[integer,optional] are (9) secondary operators used by the main operator.

The remaining of this paper functions as a reference of the main functions and subroutines available in the current version of oclib. Appendices F and F present a simple example (the Makefile and the main program).

Next table presentes a list of the main Fortran90 modules that compose the library.

Algebraic operations on files module oc_file_mod module of_filealgebra_mod module oc_filter_mod

Out-of-core operators module oc_adjnull_mod module oc_scale_mod module oc_weight_mod module oc_helicon_mod module oc_polydiv_mod module oc_laplacian_mod module oc_helocut_mod module oc_dottest_mod module oc_combine_mod

Out-of-core gradient solvers module oc_solver_mod module oc_solverreg_mod module oc_solverpre_mod module oc_sd_mod module oc_cg_mod module oc_cgstep_mod module oc_cd_mod module oc_gmres_mod

Out-of-core LSQR solvers module oc_lsqr_mod module oc_lsqrreg_mod module oc_lsqrpre_mod

The appendices A, B, C, and D present a detailed description of the interfaces for the main functions and subroutines in each module.