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 HO.)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.