Function detectNegative

docs/app/js/sanddance-app.js:2128–2133

(column, data)

    return stats;
}
function detectNegative(column, data) {
    for(let i = 1; i < data.length; i++){
        if (data[i][column.name] < 0) return true;
    }
    return false;
}
function detectSequentialColumn(column, data) {
    if (data.length < 2) return false;
    let colname = column.name;