int main(int argc,char *argv[])
{
	int i,N=atoi(argv[1]);
	double x=atof(argv[2]);
	poly_t p,y;

	p=polyAdd(polyTerm(1,1),polyTerm(1,0));

	for(y=p,i=1;i<N;i++){
		y=polyMult(p,y);
	}

	puts("binomial coefficients:");
	polyShow(y);
	putchar('\n');
	putchar('\n');
	printf("(%.3f+1)^%d: %.3f\n",x,N,polyEval(y,x));

	return(0);
}
poly_t polyMult(poly_t p1,poly_t p2)
{
	poly_t p;
	int i,j;
	int exp = p1->degr + p2->degr - 2;

	p=polyTerm(0,exp);
	for(i=0;i < p1->degr;i++)
		for(j=0;j < p2->degr;j++)
			p->coef[i+j] += p1->coef[i] * p2->coef[j];

	return(p);
}
Exemple #3
0
void Weights::calculateWeights()
{
    mCoefficientNumber = (mTwoDim ? ((size_t)mPolynomeOrder + 1) * ((size_t)mPolynomeOrder + 1)
                                  :  (size_t)mPolynomeOrder + 1);
    size_t  ix, iy, i, j;
    int     x, y;

    // Determine coordinates of pixels to be sampled

    if (mTwoDim)
    {

        int iPolynomeOrder = (int) mPolynomeOrder; //lets avoid signed/unsigned comparison warnings
        int iHeight        = (int) height();
        int iWidth         = (int) width();

        for (y = -iPolynomeOrder; y < iHeight + iPolynomeOrder; ++y)
        {
            for (x = -iPolynomeOrder; x < iWidth + iPolynomeOrder; ++x)
            {
                if ((x < 0 && y < 0 && -x - y < iPolynomeOrder + 2)                             ||
                    (x < 0 && y >= iHeight && -x + y - iHeight < iPolynomeOrder + 1)            ||
                    (x >= iWidth && y < 0 && x - y - iWidth < iPolynomeOrder + 1)               ||
                    (x >= iWidth && y >= iHeight && x + y - iWidth - iHeight < iPolynomeOrder)  ||
                    (x < 0 && y >= 0 && y < iHeight) || (x >= iWidth  && y >= 0 && y < iHeight) ||
                    (y < 0 && x >= 0 && x < iWidth ) || (y >= iHeight && x >= 0 && x < iWidth))
                {
                    QPoint position(x,y);
                    mPositions.append(position);
                }
            }
        }
    }
    else
    {
        // In the one-dimensional case, only the y coordinate and y size is used.  */

        for (y = (-1)*mPolynomeOrder; y < 0; ++y)
        {
            QPoint position(0,y);
            mPositions.append(position);
        }

        for (y = (int) height(); y < (int) height() + (int) mPolynomeOrder; ++y)
        {
            QPoint position(0,y);
            mPositions.append(position);
        }
    }

    // Allocate memory.

    QScopedArrayPointer<double> matrix (new double[mCoefficientNumber * mCoefficientNumber]);
    QScopedArrayPointer<double> vector0(new double[mPositions.count() * mCoefficientNumber]);
    QScopedArrayPointer<double> vector1(new double[mPositions.count() * mCoefficientNumber]);

    // Calculate coefficient matrix and vectors

    for (iy = 0; iy < mCoefficientNumber; ++iy)
    {
        for (ix = 0; ix < mCoefficientNumber; ++ix)
        {
            matrix [iy* mCoefficientNumber+ix] = 0.0;
        }

        for (j = 0; j < (size_t)mPositions.count(); ++j)
        {
            vector0 [iy * mPositions.count() + j] = polyTerm (iy, mPositions.at(j).x(),
                                                    mPositions.at(j).y(), mPolynomeOrder);

            for (ix = 0; ix < mCoefficientNumber; ++ix)
            {
                matrix [iy* mCoefficientNumber + ix] += (vector0 [iy * mPositions.count() + j]
                                                        * polyTerm (ix, mPositions.at(j).x(), mPositions.at(j).y(), mPolynomeOrder));
            }
        }
    }

    // Invert matrix.

    matrixInv (matrix.data(), mCoefficientNumber);

    // Multiply inverse matrix with vector.

    for (iy = 0; iy < mCoefficientNumber; ++iy)
    {
        for (j = 0; j < (size_t)mPositions.count(); ++j)
        {
            vector1 [iy * mPositions.count() + j] = 0.0;

            for (ix = 0; ix < mCoefficientNumber; ++ix)
            {
                vector1 [iy * mPositions.count() + j] += matrix [iy * mCoefficientNumber + ix]
                        * vector0 [ix * mPositions.count() + j];
            }
        }
    }

    // Store weights

    // Allocate mPositions.count() matrices.
    mWeightMatrices = new double** [mPositions.count()];

    for (i=0 ; i < (size_t)mPositions.count() ; ++i)
    {
        // Allocate mHeight rows on each position
        mWeightMatrices[i] = new double*[mHeight];

        for (j=0 ; j < mHeight ; ++j)
        {
            // Allocate mWidth columns on each row
            mWeightMatrices[i][j] = new double[mWidth];
        }
    }

    for (y = 0; y < (int) mHeight; ++y)
    {
        for (x = 0; x < (int) mWidth; ++x)
        {
            for (j = 0; j < (size_t)mPositions.count(); ++j)
            {
                mWeightMatrices [j][y][x] = 0.0;

                for (iy = 0; iy < mCoefficientNumber; ++iy)
                {
                    mWeightMatrices [j][y][x] += vector1 [iy * mPositions.count() + j]
                                                 * polyTerm (iy, x, y, mPolynomeOrder);
                }

                mWeightMatrices [j][y][x] *= (double) mPositions.count();
            }
        }
    }
}