背景：
读一个文件中的数据，用来训练一个小模型，发现数据中有异常值，如下：
使用pandas读数据，然后对数值类型特征，进行归一化，报错：
def minmax_norm(df): return (df - df.min()) / (df.max() - df.min())if __name__=='__main__': train_data_path = 'train_1205_shanghai.txt' test_data_path = 'test_1206_shanghai.txt' # load_data_to_df(path) col_name = ['a','b','c'] train_data = pd.read_table(train_data_path, header=None) train_data.columns = col_name test_data = pd.read_table(test_data_path, header=None) test_data.columns = col_name # print(data.head(3)) 'avg_rider_done_ord_cnt' number_feat = ['a','b'] for i in range(len(number_feat)): train_data[[number_feat[i]]] = minmax_norm(train_data[[number_feat[i]]]) test_data[[number_feat[i]]] = minmax_norm(test_data[[number_feat[i]]])报错：
Traceback (most recent call last): File "/Users/alsc/.conda/envs/algoTest/lib/python3.6/site-packages/pandas/core/ops/array_ops.py", line 143, in na_arithmetic_op result = expressions.evaluate(op, left, right) File "/Users/alsc/.conda/envs/algoTest/lib/python3.6/site-packages/pandas/core/computation/expressions.py", line 233, in evaluate return _evaluate(op, op_str, a, b) # type: ignore File "/Users/alsc/.conda/envs/algoTest/lib/python3.6/site-packages/pandas/core/computation/expressions.py", line 68, in _evaluate_standard return op(a, b)TypeError: unsupported operand type(s) for -: 'str' and 'float'排查：
这个错误的意思：类型有错误，不能将str和float类型的数据进行相减‘-’。
划重点，终于知道了【for -:】是什么意思，就是在减号处，出现了类型不匹配的问题，想修复问题，就去减号附近看看有没有涉及到不同类型计算的。
解决：
删除数据中的异常值。
来源地址：https://blog.csdn.net/pearl8899/article/details/128487536
