def ColumnValidator(parent, filepointer, nCol=5):
    """Validate a file to check that it contains columns of numbers"""
    l = filepointer.readline()
    line = 1
    while l[0] in ['#', '(']:
        l = filepointer.readline()
        line += 1
    for i in range(10):
        S = l.split()
        if len(S) < nCol:
            parent.errors = 'line ' + str(line) + ': invalid input\n' + l
            return False
        for v in S[:nCol]:
            try:
                float(v)
            except ValueError:
                parent.errors = 'line ' + str(line
                    ) + """: string found where a number is expected
""" + l
                return False
        l = filepointer.readline()
        line += 1
    return True
