View: bcround

Function:
Description: Function to round bc string.
Code
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function bcround (val, precision) {
    // http://jsphp.co/jsphp/fn/view/bcround
    // +   original by: lmeyrick (https://sourceforge.net/projects/bcmath-js/)
    // -    depends on: _phpjs_shared_bc
    // *     example 1: bcround(1, 2);
    // *     returns 1: 3
    //  @todo: implement these testcases
    //        bcscale(0);
    //
    //        bcmath.test.result('bcround', 1, '-2', bcround('-1.5', 0));
    //        bcmath.test.result('bcround', 2, '-1.1235', bcround('-1.1234567', 4));
    //        bcmath.test.result('bcround', 3, '2', bcround('1.5', 0));
    //        bcmath.test.result('bcround', 4, '1.1235', bcround('1.1234567', 4));
    //        bcmath.test.result('bcround', 5, '1', bcround('1.499999999', 0));
    //        bcmath.test.result('bcround', 6, '2', bcround('1.5555555555555555555', 0));
    //        bcmath.test.result('bcround', 7, '1.44', bcround('1.444999', 2));
    //        bcmath.test.result('bcround', 8, '-1.44', bcround('-1.444999', 2));
    var libbcmath = this._phpjs_shared_bc();

    var temp, result, digit;
    var right_operand;

    // create number
    temp = libbcmath.bc_init_num();
    temp = libbcmath.php_str2num(val.toString());

    // check if any rounding needs
    if (precision >= temp.n_scale) {
        // nothing to round, just add the zeros.
        while (temp.n_scale < precision) {
            temp.n_value[temp.n_len + temp.n_scale] = 0;
            temp.n_scale++;
        }
        return temp.toString();
    }

    // get the digit we are checking (1 after the precision)
    // loop through digits after the precision marker
    digit = temp.n_value[temp.n_len + precision];

    right_operand = libbcmath.bc_init_num();
    right_operand = libbcmath.bc_new_num(1, precision);

    if (digit >= 5) {
        //round away from zero by adding 1 (or -1) at the "precision".. ie 1.44999 @ 3dp = (1.44999 + 0.001).toString().substr(0,5)
        right_operand.n_value[right_operand.n_len + right_operand.n_scale - 1] = 1;
        if (temp.n_sign == libbcmath.MINUS) {
            // round down
            right_operand.n_sign = libbcmath.MINUS;
        }
        result = libbcmath.bc_add(temp, right_operand, precision);
    } else {
        // leave-as-is.. just truncate it.
        result = temp;
    }

    if (result.n_scale > precision) {
        result.n_scale = precision;
    }
    return result.toString();
}
Comment on bcround version 81
Tests
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