C++ Objective AlgLib

Question

I have an c++ code. that i have to use in objective c.

double[,] x = new double[,]{{-1},{-0.8},{-0.6},{-0.4},{-0.2},{0},{0.2},{0.4},{0.6},{0.8},{1.0}};
double[] y = new double[]{0.223130,0.382893,0.582748,0.786628,0.941765,1.000000,0.941765,0.786628,0.582748,0.382893,0.223130};
double[] c = new double[]{0.3};

double epsf = 0;
double epsx = 0.000001;

int maxits = 0;
int info;

alglib::lsfitstate state;
alglib::lsfitreport rep;

double diffstep = 0.0001;    

//
// Fitting with weights
// (you can change weights and see how it changes result)
//

double[] w = new double[]{1,1,1,1,1,1,1,1,1,1,1};

alglib::lsfitcreatewf(x, y, w, c, diffstep, out state);
alglib::lsfitsetcond(state, epsf, epsx, maxits);
alglib::lsfitfit(state, function_cx_1_func, null, null);
alglib::lsfitresults(state, out info, out c, out rep);

i already called my objective file at the end with .mm

But i get difference Errors. (first lines - expected expression when i init my vars).

I can't c++ . But i only need this one function.

I hope that this is a solution for this question. https://gis.stackexchange.com/questions/74567/math-algorithm-for-n-amount-points-in-objective-c

Answer 1

That is mostly Java code at the beginning for the array declarations, not C, C++ or ObjC.

This would be C/C++ code:

double x[][1] = {{-1},{-0.8},{-0.6},{-0.4},{-0.2},{0},{0.2},{0.4},{0.6},{0.8},{1.0}};
double y[] = {0.223130,0.382893,0.582748,0.786628,0.941765,1.000000,0.941765,0.786628,0.582748,0.382893,0.223130};
double c[] = {0.3};

However, according to the lsfitcreatewf function reference here , you need it to be of the type alglib::real_2d_array . There are some examples here how to generate such data.

Here and following are some general examples about how to use the lsfit subpackage.