invalid batch

[scalaboy]

请问下，这个invalid batch 是怎么个逻辑计算的？代码没看明白、

    raw_arr = np.column_stack((preds, labels))
    raw_arr = sorted(raw_arr, key=lambda d: d[0])

    auc = 0.
    fp1, tp1, fp2, tp2 = 0., 0., 0., 0.
    for record in raw_arr:
        fp2 += 1 - record[1]
        tp2 += record[1]
        auc += (fp2 - fp1) * (tp2 + tp1)
        fp1, tp1 = fp2, tp2

    threshold = len(preds) - 1e-3
    if tp2 > threshold or fp2 > threshold:
        print('%s invalid batch' % self.name)
        return