def str_is_pos_float(numeric_string):
    """Returns true if the string is a positive float
    
    Arguments
    ---------
    string : str 
        String representing a number
    
    Returns
    -------
    bool
        True if the string is a positive float
    """
    is_float = False
    if numeric_string:
        if numeric_string.replace('.', '', 1).isdigit():
            if '.' in numeric_string:
                is_float = True
    return is_float
