2.1.17.8.19 ocmath_us_stretch

Description

Stretch (or squeeze) data in a vector or a matrix of type double by scaling all the data within a given range.

Syntax

int ocmath_us_stretch( USHORT * pX, uint nSize, USHORT low1, USHORT high1, USHORT low2, USHORT high2 )

Parameters

pX

[modify] pointer to vector or matrix data

nSize

[input] size of vector, or nRows * nCols of a matrix

low1

[input] low value of the range of data to be scaled, for data < low1, they will become low2

high1

[input] high value of the range of data to be scaled, for data > high1, they will become high2

low2

[input] new low value of the data after the scaling

high2

[input] new high value of the data after the scaling

Return

FALSE if low1 == high1 which renders the operation impossible, otherwise returns TURE

Examples

EX1

// Create two identical matrices, use ocmath_d_stretch on one and plot both
void    ocmath_us_stretch_Ex1()
{
    MatrixPage        mp1;
    mp1.Create("origin", CREATE_VISIBLE);
    MatrixObject        mo1(mp1.GetName(), 0);
    LT_execute("matrix -v 50-abs(16.5-i)-abs(16.5-j);");

    MatrixPage        mp2;
    mp2.Create("origin", CREATE_VISIBLE);
    MatrixObject        mo2(mp2.GetName(), 0);
    LT_execute("matrix -v 50-abs(16.5-i)-abs(16.5-j);");

    matrix                mat;
    mat = mo1.GetDataObject();
    int                    nRows, nCols;
    mat.GetSourceDim(nRows, nCols);
    // Values in the range 25 to 35 will be squeezed into a range from 0 to 10
    // Values less than 25 become 0 and values greater than 35 become 10
    ocmath_d_stretch(mat, nRows * nCols, 25, 35, 0, 10);
    
    GraphPage        gp1;
    gp1.Create("cmap", CREATE_VISIBLE);
    GraphLayer        gl1(gp1.GetName());
    gl1.AddPlot(mo1, IDM_PLOT_SURFACE_COLORMAP);
    gl1.Rescale();

    GraphPage        gp2;
    gp2.Create("cmap", CREATE_VISIBLE);
    GraphLayer        gl2(gp2.GetName());
    gl2.AddPlot(mo2, IDM_PLOT_SURFACE_COLORMAP);
    gl2.Rescale();
}

Remark

Stretch (or squeeze) data in a vector or a matrix of type double by scaling all the data within a given range.

Values outside the given range are truncated.

Data types supported

double: ocmath_d_stretch

float: ocmath_f_stretch

unsigned short: ocmath_us_stretch

See Also

ocmath_f_stretch

Header to Include

origin.h

Reference