package symjava.examples;

import symjava.bytecode.BytecodeBatchFunc;

import symjava.math.SymMath;

import symjava.symbolic.Expr;

import symjava.symbolic.Symbol;

import symjava.symbolic.Symbols;

import symjava.symbolic.utils.AddList;

import symjava.symbolic.utils.JIT;

import symjava.symbolic.utils.MulList;

//http://www.sfu.ca/~ssurjano/griewank.html

public class BenchmarkGriewank {

public static void main(String[] args) {

test();

}

public static void test() {

// TODO Auto-generated method stub

int N = 50;

long start;

Symbol i = new Symbol("i");

Symbols xi = new Symbols("x", i);

start = System.currentTimeMillis();

AddList term1 = new AddList();

for (int j = 0; j < N; j++) {

term1.add(xi.get(j) * xi.get(j) / 4000.0);

}

MulList term2 = new MulList();

for (int j = 0; j < N; j++) {

term2.add(SymMath.cos(xi.get(j) / Math.sqrt(j + 1)));

}

Expr griewank = term1.toExpr() - term2.toExpr() + 1.0;

//System.out.println(griewank);

Expr[] grad = new Expr[N];

for(int j=0;j<N;j++)

grad[j] = griewank.diff(xi.get(j));

long symbolTime = System.currentTimeMillis() - start;

Expr[] args = xi.get(0, N);

start = System.currentTimeMillis();

BytecodeBatchFunc f = JIT.compileBatchFunc(args, grad);

long compileTime = System.currentTimeMillis() - start;

double[] outAry = new double[N];

double[] params = new double[N];

for(int j=0; j<N; j++) {

params[j] = 0.1;

}

f.apply(outAry, 0, params);

for(int j=0;j<N;j++)

System.out.println(outAry[j]);

System.out.println("symbol time: "+symbolTime/1000.0);

System.out.println("compile time: "+compileTime/1000.0);

}

}