get_dataplot_index

Description

For x value, find the nearest point from a data plot and returns the index of this point.

Syntax

int get_dataplot_index( DataPlot & dp, double x, DWORD dwCntrl = XIC_NEAREST_ANY )

Parameters

dp

[input] data plot object

x

[input] give x value to find point

dwCntrl

[input] control of the way to decide how to find the nearest point, default is XIC_NEAREST_ANY

Return

-1 if no point found, else returns the index of the point.

Examples

EX1

void get_dataplot_index_ex1()
{
    WorksheetPage wksPage;
    wksPage.Create("Origin");
    
    Worksheet wks = wksPage.Layers();
    Dataset dsA(wks, 0);
    Dataset dsB(wks, 1);
    
    dsA.Data(1, 10, 1);
    dsB.Data(1, 10, 1);
    
    GraphPage gp;
    gp.Create();
    
    GraphLayer gl = Project.ActiveLayer();
    gl.AddPlot(wks);
    DataPlot dp = gl.DataPlots();
    
    int     index = -1;
    double     x = 5.3;
    DWORD    dwCntrl = XIC_NEAREST_ANY;  
    
    index = get_dataplot_index(dp, x, dwCntrl); // index is 4, find the nearest one
    printf("X is %f and dwCntrl is %d, the index of data point will be %d\n", x, dwCntrl, index);
    
    
    dwCntrl = XIC_NEAREST_RIGHT;  
    index = get_dataplot_index(dp, x, dwCntrl); // index is 5, find the right one
    printf("X is %f and dwCntrl is %d, the index of data point will be %d\n", x, dwCntrl, index);    
}

Remark

See Also

header to Include

origin.h

Reference