'Validate a gg file - all numeric after header row'

def validate(self, dataset):

    errors = list()
    with open(dataset.file_name, 'r') as infile:
        next(infile)
        for (i, row) in enumerate(infile):
            ll = row.strip().split(' DCTB ')[1:]
            badvals = []
            for (j, x) in enumerate(ll):
                try:
                    x = float(x)
                except:
                    badvals.append(('col%d:%s' % ((j + 1), x)))
    if (len(badvals) > 0):
        errors.append(('row    %d,    %s' % '    '.join(badvals)))
        return errors
