How do I configure AlgLib for VS2017? - c++

Question

I am compiling a alglib sample program (with a few changes):
#pragma once
# include "Source\RFLearn.h" \\appropriate header for this simple .cpp program.
# include <LinAlg.h>
# include <stdint.h>
# include <chrono> // for in-game frame clock.
int RFLearn::test_function()
{
alglib::real_2d_array a, b, c;
int n = 2000;
int i, j;
double timeneeded, flops;
// Initialize arrays
a.setlength(n, n);
b.setlength(n, n);
c.setlength(n, n);
for (i = 0; i<n; i++)
for (j = 0; j<n; j++)
{
a[i][j] = alglib::randomreal() - 0.5;
b[i][j] = alglib::randomreal() - 0.5;
c[i][j] = 0.0;
}
// Set global threading settings (applied to all ALGLIB functions);
// default is to perform serial computations, unless parallel execution
// is activated. Parallel execution tries to utilize all cores; this
// behavior can be changed with alglib::setnworkers() call.
alglib::setglobalthreading(alglib::parallel);
// Perform matrix-matrix product.
flops = 2 * pow((double)n, (double)3);
auto timer_start = std::chrono::high_resolution_clock::now();
alglib::rmatrixgemm(
n, n, n,
1.0,
a, 0, 0, 0,
b, 0, 0, 1,
0.0,
c, 0, 0);
auto timer_end = std::chrono::high_resolution_clock::now();
auto duration = timer_end - timer_start;
timeneeded = static_cast<double>(duration.count());
// Evaluate performance
printf("Performance is %.1f GFLOPS\n", (double)(1.0E-9*flops / timeneeded));
return 0;
}
I am confident linAlg is correctly linked (as well as all of its dependencies, particularly ap.h and ap.cpp) (Preferences->C++->AllOptions->Additional Include Directories -> aglib's source directory. Changing the link provides a different set of linker errors. AlgLib is a header only-library so I don't think I need to compile any library and add it in the linker.
When compiling this code I get the errors:
1>RFLearn.obj : error LNK2001: unresolved external symbol "public: double * __thiscall alglib::real_2d_array::operator[](int)" (??Areal_2d_array#alglib##QAEPANH#Z)
1>RFLearn.obj : error LNK2001: unresolved external symbol "public: virtual __thiscall alglib::real_2d_array::~real_2d_array(void)" (??1real_2d_array#alglib##UAE#XZ)
1>RFLearn.obj : error LNK2001: unresolved external symbol "public: __thiscall alglib::real_2d_array::real_2d_array(void)" (??0real_2d_array#alglib##QAE#XZ)
1>RFLearn.obj : error LNK2001: unresolved external symbol "struct alglib::xparams const & const alglib::parallel" (?parallel#alglib##3ABUxparams#1#B)
1>RFLearn.obj : error LNK2001: unresolved external symbol "void __cdecl alglib::rmatrixgemm(int,int,int,double,class alglib::real_2d_array const &,int,int,int,class alglib::real_2d_array const &,int,int,int,double,class alglib::real_2d_array const &,int,int,struct alglib::xparams)" (?rmatrixgemm#alglib##YAXHHHNABVreal_2d_array#1#HHH0HHHN0HHUxparams#1##Z)
1>RFLearn.obj : error LNK2001: unresolved external symbol "double __cdecl alglib::randomreal(void)" (?randomreal#alglib##YANXZ)
1>RFLearn.obj : error LNK2001: unresolved external symbol "public: void __thiscall alglib::ae_matrix_wrapper::setlength(int,int)" (?setlength#ae_matrix_wrapper#alglib##QAEXHH#Z)
1>RFLearn.obj : error LNK2001: unresolved external symbol "void __cdecl alglib::setglobalthreading(struct alglib::xparams)" (?setglobalthreading#alglib##YAXUxparams#1##Z)
1>RFLearn.obj : error LNK2001: unresolved external symbol "struct alglib::xparams const & const alglib::xdefault" (?xdefault#alglib##3ABUxparams#1#B)
I intuit that the problem lies around here: http://www.alglib.net/translator/man/manual.cpp.html#gs_configuring
but I cannot make heads or tails of it. What's the next step?

Answer 1

I had a similar (not exact) problem and it went away just by adding the compiled the cpp files to my project and set "included in the project" to true.