ocmath_2d_spline_grid

 

Description

This function computes a bicubic spline approximation to a set of data values, given on an equi-spaced rectangular grid in the x-y plane. The smoothness of fit can be controlled.

Syntax

int ocmath_2d_spline_grid( const uint nrSrc, const uint ncSrc, const double * pmatSrc, const uint nrDest, const uint ncDest, double * pmatDest, double dSmoothFactor = 0 )

Parameters

nrSrc
[input] The number of rows of source matrix.
ncSrc
[input] The number of cols of source matrix.
pmatSrc
[input] Source matrx.
nrDest
[input] The number of rows of output matrx.
ncDest
[input] The number of cols of output matrix.
pmatDest
[output] Output matrix.
dSmoothFactor
[input] The smoothing factor. Constraint: dSmoothFactor >= 0.

Return

Return 0 if succeed, or a non-zero Nag error codes:

NE_NULL_ARRAY = 82: pmatSrc and pmatDest must not be NULL.

NE_INT_ARG_LT = 11: nrSrc and ncSrc must not be less than 4, and nrDest, ncDest must not be less than 1.

NE_REAL_ARG_LT = 5: dSmoothFactor must be bigger than 0.

NE_SPLINE_COEFF_CONV = 263: The iterative process has failed to converge. Possibly dSmoothFactor is too small.

NE_ALLOC_FAIL = 73: Memory allocation failed.

Examples

EX1

//Before running, make sure a matrixlayer exists and is active in current project
void ocmath_2d_spline_grid_ex1(double smooth)
{
    MatrixLayer ml = Project.ActiveLayer();
    MatrixObject mo = ml.MatrixObjects(0);
    if (!mo.IsValid())
        printf("Error: MatrixObject is invalid!\n");
    
    Matrix& mat = mo.GetDataObject();
    
    int nRows = mo.GetNumRows();
    int nCols = mo.GetNumRows();
    
    int rows,cols;
    rows = nRows;
    cols = nCols;
    matrix matDest(rows, cols);
    
    int iRet;
    
    iRet = ocmath_2d_spline_grid(nRows, nCols, mat, rows, cols, matDest, smooth);
    
    if (iRet == 0)
        mat = matDest;
    else
        printf("Error: Nag code is %d\n", iRet);
}

Remark

See Also

header to Include

origin.h

Reference

nag_2d_spline_fit_grid(e02dcc)nag_2d_spline_fit_grid(e02dcc), NAG Manual