var _ = require("lodash");

function _f2(n) {
    var n1 = _.round(_.toNumber(n), 6);
    return _.floor(n1, 2).toFixed(2);
}

function _f2x(n) {
    var n1 = _.round(_.toNumber(n), 6);
    var n1_str = _.toString(n1);
    if (n1_str === "3.175" || n1_str === "3.101") {
        return n1_str;
    }
    if (/\d+\.\d[2|7]/.test(n1_str)) {
        return /\d+\.\d[2|7]/.exec(n1_str)[0] + '5';
    }

    return _.floor(n1, 2).toFixed(2);
}


print(_f2(3.4056));
print(_f2x(3.4056));
print(_f2x(3.4746));
print(_f2x(3.4266));
print(_f2x(3.175));
print(_f2x(3.101));
print(_f2x(3.174999999));
print(_f2x(3.1010001));