matlab_抛物线圆柱函数C++快速版

# Parabolic Cylinder Functions C++ Version This project is a faster version of MATLAB code original from E. Cojocaru. Parabolic Cylinder Functions (https://www.mathworks.com/matlabcentral/fileexchange/22620-parabolic-cylinder-functions) The API is similar to original functions, such as `val = pwlx(a,x);` -> `val = pcf_mex(a,x,'pwlx');` The MATLAB toolbox only support scalar inputs, pcf_mex now support 1D array of size (1,n) or (n,1), return value will have size(n,1). Intel compiler, OPENMP， AVX2 or AVX512 are utilized to speed up the calculation. I tested it with simple benchmark : pcf_mex(-1,linspace(4,5,1e6),'pwlx'), unit is seconds % 0.3994 intel compiler 2021 + openmp + avx2 % 1.0733 vs + openmp + avx2 % 1.0858 vs + openmp % 9.7933 vs % 4.476539 original + parfor % 32.521651 original The first one is compiled with Visual Studio + Intel OneAPI, intel compiler 2021 is much more faster.