Routine to initialize the SAXSDATA structure. Here the sampling in reciprocal space needs to be specified; currently only equidistant sampling is possible. Moreover, the parameters for the scoring function and for its computation are set.

s_minands_maxspecify the minimum and maximum frequency in reciprocal space, in Å .maxsgives the maximum number of frequencies, andnmeshthe actual number (which must be less thanmaxs).

natomtypgives the number of ''atoms'',i.e.scattering centers.represtypspecifies the representation : 'heav', 'allh', or 'CA'.filenameis the name of the library for formfactors.wswitchis the character for filter of scoring function: 'unity', 'sq', or 'hybrid'. If 'hybrid', thens_hybridis the frequency above which weighting is applied.s_lowands_higive the lower and upper cutoff for the bandpass filter in Å .spaceflagspecifies how should be computed. 'real' space via or 'reciprocal'. 'real' is more than a magnitude faster but less accurate for high resolution ( ).

rho_solvgives the electron density of solvent, in Å . (The default 0.334 corresponds to H O.)use_lookup, ifTrue, uses lookup tables for SINC and COS functions, giving a significant increase in speed for 'reciprocal' mode.

nrgives the number of points for sampling, anddrthe spacing of these points in Å.nr_expgives the number of points for sampling, anddr_exptheir spacing.

Ifuse_offsetisTruethen allowance is made for an additive constant in the experimental spectrum. Ifuse_rolloffisTrue, allowance is made for Gaussian rolloff in the model spectrum. Ifuse_convisTrue, the spectrum is multiplied with the formfactor of nitrogen ( 3Å) spectrum. IfmixflagisTruethen more than one conformation is modeled simultaneously. Ifpr_smoothisTruesmoothing of p(r) is done.