AutoFilter: top N number of items to filter by

The FilterColumn::setTop10() method sets the number of top or bottom items in AutoFilter:

#include "libxl.h"

using namespace libxl;

int main()
{
    Book* book = xlCreateXMLBook();
    
    Sheet* sheet = book->addSheet(L"my");

    sheet->writeStr(2, 1, L"Country");
    sheet->writeStr(2, 2, L"Road injures");
    sheet->writeStr(2, 3, L"Smoking");
    sheet->writeStr(2, 4, L"Suicide");

    sheet->writeStr(3, 1, L"USA");     sheet->writeStr(4, 1, L"UK"); 
    sheet->writeNum(3, 2, 64);         sheet->writeNum(4, 2, 94);
    sheet->writeNum(3, 3, 69);         sheet->writeNum(4, 3, 55);
    sheet->writeNum(3, 4, 49);         sheet->writeNum(4, 4, 64);

    sheet->writeStr(5, 1, L"Germany"); sheet->writeStr(6, 1, L"Switzerland");
    sheet->writeNum(5, 2, 88);         sheet->writeNum(6, 2, 93); 
    sheet->writeNum(5, 3, 46);         sheet->writeNum(6, 3, 54);
    sheet->writeNum(5, 4, 55);         sheet->writeNum(6, 4, 50);

    sheet->writeStr(7, 1, L"Spain");   sheet->writeStr(8, 1, L"Italy"); 
    sheet->writeNum(7, 2, 86);         sheet->writeNum(8, 2, 75); 
    sheet->writeNum(7, 3, 47);         sheet->writeNum(8, 3, 52);
    sheet->writeNum(7, 4, 69);         sheet->writeNum(8, 4, 71);

    sheet->writeStr(9, 1, L"Greece");  sheet->writeStr(10, 1, L"Japan");
    sheet->writeNum(9, 2, 67);         sheet->writeNum(10, 2, 91);
    sheet->writeNum(9, 3, 23);         sheet->writeNum(10, 3, 57);
    sheet->writeNum(9, 4, 87);         sheet->writeNum(10, 4, 36);

    AutoFilter* autoFilter = sheet->autoFilter();
    autoFilter->setRef(2, 10, 1, 4);
    
    // shows 3 countries with the safest roads

    FilterColumn* column = autoFilter->column(1);
    column->setTop10(3); 

    sheet->applyFilter();
   
    book->save(L"out.xlsx");

    book->release();
    
    return 0;
}

See also other AutoFilter examples: