Search Results for "absolute"

...The code is presently interfaced with the WIEN2k package. The algorithm of the code is based on the Nelder-Mead’s function-minimization approach. The code minimizes the function f(k), which is defined as sum of the absolute energy difference of the adjacent pairs of bands at a given k-point. Please cite the paper mentioned below while using the PY-Nodes code for your research. V. Pandey and S.K. Pandey, Comput. Phys. Commun. 283, 108570 (2023). The link of the paper: https://doi.org/10.1016/j.cpc.2022.108570

Keywords: -simultaneously fit several SAXS and SANS data sets with polydisperse (Schultz-Zimm or Gaussian distribution f(R)) spherical core-shell-shell nanoparticles -analytical expressions are used for from factor F(Q) and its integral over f(R), no numerical integration required -absolute units -Mathematica is required via console (MathKernel) -Mathematica's local and global optimizers (simulated annealing, differential evolution, Nelder-Mead, ...) can be used -range for fit parameters and further constraints between fit parameters are possible -Monodisperse(!) hard sphere structure factor can be used, too -long computation times (depending on problem size and amount of constraints) from hours to a few days are possible -non-parallelized code

Keywords (XNDiff): -SAXS -SANS -absolute units -core (double)shell crystalline nanoparticles -with a parallelepidal shape -particle assemblies -powder and ensemble average -C/C++ -Unix -OpenMP -HPC Cluster Keywords (BatchMultiFit): -simultaneous fits for several SAXS and SANS curves with simulation data from XNDiff -SANS data can be smeared with dq values from experimental data sets or analytical functions -Mathematica console -local and global optimizers (simulated annealing, differential evolution, Nelder-Mead, ...) can be used -range for fit parameters and further constraints between fit parameters -parallelized (typ. 4-8 threads) TODO (BatchMultiFit): -read and use errorbars from experimental data sets -allow different q-ranges for different data sets in the fits -rewrite and test in Python using e.g. the lmfit module: https://pypi.python.org/pypi/lmfit/ to get rid of Mathematica and to run it on HPC clusters

...Please use the repository at https://github.com/Niels-Bohr-Institute-XNS-StructBiophys/fit2dcorr for the new updated versions. The old version is kept at sourceforge. Keywords: fit2d SAXS azimuthal averaging batch processing absolute units (exposure time, transmission, sample thickness) error bars C++ Unix OpenMP