在这个简短的指南中，我将向你展示几种在Python中只打印错误信息而不打印回溯的选项。
这对于演示或当你有不需要的极长的信息时非常有用。
选项1：用SystemExit(err)打印没有回溯的错误信息
我们将使用的第一个选项是：SystemExit(err) 。
我们将捕获任何异常并处理它。然后我们将只打印出错误信息。
要想只显示错误信息，请使用下面的语法:
try:
pd.to_datetime(df['date'])
except Exception as err:
raise SystemExit(err)
result:
An exception has occurred, use %tb to see the full traceback.
SystemExit: Out of bounds nanosecond timestamp: 1-06-13 00:00:00
默认情况下，下面的代码
import pandas as pd
pd.to_datetime(df['date'])
会产生很长的错误信息:
---------------------------------------------------------------------------
TypeError Traceback (most recent call last)
/home/myuser/Software/Tensorflow/environments/venv36/lib/python3.6/site-packages/pandas/core/arrays/datetimes.py in objects_to_datetime64ns(data, dayfirst, yearfirst, utc, errors, require_iso8601, allow_object)
2058 try:
-> 2059 values, tz_parsed = conversion.datetime_to_datetime64(data)
2060 # If tzaware, these values represent unix timestamps, so we
pandas/_libs/tslibs/conversion.pyx in pandas._libs.tslibs.conversion.datetime_to_datetime64()
TypeError: Unrecognized value type: <class 'str'>
During handling of the above exception, another exception occurred:
OutOfBoundsDatetime Traceback (most recent call last)
<ipython-input-20-6dea9b57a428> in <module>()
----> 1 pd.to_datetime(df['date'])
/home/myuser/Software/Tensorflow/environments/venv36/lib/python3.6/site-packages/pandas/core/tools/datetimes.py in to_datetime(arg, errors, dayfirst, yearfirst, utc, format, exact, unit, infer_datetime_format, origin, cache)
801 result = arg.map(cache_array)
802 else:
--> 803 values = convert_listlike(arg._values, format)
804 result = arg._constructor(values, index=arg.index, name=arg.name)
805 elif isinstance(arg, (ABCDataFrame, abc.MutableMapping)):
/home/myuser/Software/Tensorflow/environments/venv36/lib/python3.6/site-packages/pandas/core/tools/datetimes.py in _convert_listlike_datetimes(arg, format, name, tz, unit, errors, infer_datetime_format, dayfirst, yearfirst, exact)
464 errors=errors,
465 require_iso8601=require_iso8601,
--> 466 allow_object=True,
467 )
468
/home/myuser/Software/Tensorflow/environments/venv36/lib/python3.6/site-packages/pandas/core/arrays/datetimes.py in objects_to_datetime64ns(data, dayfirst, yearfirst, utc, errors, require_iso8601, allow_object)
2062 return values.view("i8"), tz_parsed
2063 except (ValueError, TypeError):
-> 2064 raise e
2065
2066 if tz_parsed is not None:
/home/myuser/Software/Tensorflow/environments/venv36/lib/python3.6/site-packages/pandas/core/arrays/datetimes.py in objects_to_datetime64ns(data, dayfirst, yearfirst, utc, errors, require_iso8601, allow_object)
2053 dayfirst=dayfirst,
2054 yearfirst=yearfirst,
-> 2055 require_iso8601=require_iso8601,
2056 )
2057 except ValueError as e:
pandas/_libs/tslib.pyx in pandas._libs.tslib.array_to_datetime()
pandas/_libs/tslib.pyx in pandas._libs.tslib.array_to_datetime()
pandas/_libs/tslib.pyx in pandas._libs.tslib.array_to_datetime()
pandas/_libs/tslib.pyx in pandas._libs.tslib.array_to_datetime()
pandas/_libs/tslibs/conversion.pyx in pandas._libs.tslibs.conversion.convert_datetime_to_tsobject()
pandas/_libs/tslibs/np_datetime.pyx in pandas._libs.tslibs.np_datetime.check_dts_bounds()
OutOfBoundsDatetime: Out of bounds nanosecond timestamp: 1-06-13 00:00:00
选项2：用traceback.print_exc(limit=1)打印没有跟踪的错误信息
还有一个替代方案是使用traceback.print_exc(limit=1) ，其用法如下：
import pandas as pd
import traceback
try:
pd.to_datetime('Jun 1, 1111')
except Exception as e:
traceback.print_exc(limit=1)
exit(1)
结果错误将是：
Traceback (most recent call last):
File "/home/vanx/Software/Tensorflow/environments/venv36/lib/python3.6/site-packages/pandas/core/arrays/datetimes.py", line 2059, in objects_to_datetime64ns
values, tz_parsed = conversion.datetime_to_datetime64(data)
TypeError: Unrecognized value type: <class 'str'>
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "<ipython-input-22-ee6c6bd48a55>", line 5, in <module>
pd.to_datetime('Jun 1, 1111')
pandas._libs.tslibs.np_datetime.OutOfBoundsDatetime: Out of bounds nanosecond timestamp: 1111-06-01 00:00:00
选项3：用sys.trackbacklimit打印没有回溯的错误信息
最后，你可以通过以下方式减少回溯的限制。sys.tracebacklimit.
要设置回溯的最低水平，请使用：
import sys
sys.tracebacklimit = 0
