def _float(value: str) -> float:
    """Convert string to float value

    Convert a string to a floating point number (including, e.g. -0.5960D-01). Whitespace or empty value is set to 0.0.

    Args:
        value:   string value

    Returns:
        Float value
    """
    if value.isspace() or not value:
        return 0.0
    else:
        return float(value.replace("D", "e"))