2.2.3.19.41 vectorbase::TrimLeft

TrimLeft

1 Description
2 Syntax
3 Parameters
4 Return
5 Examples
6 Remark
7 See Also
8 Header to Include

Description

Removes elements having the missing value (NANUM) from the left end of the vector.

Syntax

int TrimLeft( BOOL bShiftLeft = FALSE )

Parameters

bShiftLeft: [input] TRUE will delete cells on the left of (before) the first valid numeric value, FASLE will cause the lower bound or index to be adjusted upward but no cells are deleted.

Return

Returns -1 on error, 0 on success, and N > 0 for number of cells deleted.

Examples

EX1

//Case1: bShiftLeft = FALSE using in vector. will keep the vector not delete NANUM
void vectorbase_TrimLeft_ex1()
{
    vector vecData = {0.1, 0.2, 0.3, 0.4};
    vecData[0] = NANUM;
    //    vecData = {NANUM, 0.2, 0.3, 0.4}
    // Now using function trimleft to trim the vector's left
    vecData.TrimLeft();
    for(int ii = 0; ii < vecData.GetSize(); ii++)
    	out_double("",vecData[ii]);
    // Result:
    //        vecData = {NANUM, 0.2, 0.3, 0.4}
    
}

EX2

//Case2: bShiftLeft = TRUE using in vector. will Remove Left NANUM
void vectorbase_TrimLeft_ex2()
{
    vector vecData = {0.1, 0.2, 0.3, 0.4};
    vecData[0] = NANUM;
    vecData[1] = NANUM;
    //    vecData = {NANUM, NANUM, 0.3, 0.4}
    // Now using function trimleft to trim the vector's left
    int nRet = vecData.TrimLeft(true);
    for(int ii = 0; ii < vecData.GetSize(); ii++)
    	out_double("",vecData[ii]);
    // Result:
    //        vecData = {0.3, 0.4}
}

EX3

void vectorbase_TrimLeft_ex3()
{
    // The current window is Worksheet with two columns
    Worksheet wks=Project.ActiveLayer();
    if (wks)
    {
        Dataset dsA(wks,0);
        Dataset dsB(wks,1);
        dsA.TrimLeft(TRUE);
        Curve crvAxBy(dsA,dsB);
        crvAxBy.TrimLeft(TRUE);
        LT_execute("doc -uw");
    }
}

EX4

//Case4: bShiftLeft = TRUE in Curve.
void vectorbase_TrimLeft_ex4()
{
    vector vX = {1, 2, 3, 4};
    vector vY = {0.1, 0.2, 0.3, 0.4};
    vX[0] = NANUM;
    vX[1] = NANUM;
    Curve crv(vX, vY);
    //    crv = {(NANUM,0.1), (NANUM,0.2), (3,0.3),(4, 0.4)}
    // Now using function trimleft to trim the Curve's left
    crv.TrimLeft(true);

    // Result:
    //    crv = {(3,0.3),(4, 0.4)}
}

Remark

TrimLeft removes elements having the missing value from the left end or beginning of the vectorbase derived object by advancing the lower index to the first valid numeric value. If bShiftLeft is TRUE cells containing NANUM are deleted from the vectorbase object and a lower index value of 0 is returned shifting numeric values left. bShiftLeft must be TRUE. For vectors or this function will have no effect. When bShiftLeft is TRUE TrimLeft of Curve objects causes both X and Y Datasets to be trimmed.