Suppose I am given a partial datetime string. I wish to obtain the datetime it represents, and what was the resolution of the given datetime.

For example:

• "2021-01-06 12" -> 2021-01-06 12:00:00.000000 and "hour"
• "2020-03" -> 2020-03-01 00:00:00.000000 and "month"
• "2020-03-01" -> 2020-03-01 00:00:00.000000 and "day"

The idea is to use a given partial datetime-string as a time-range specification. Meaning that instead of writing "All of March, 2020", just write "2020-03".

The question can be reduced to an answer with the pandas framework, though given a partial string like in the above examples, pd.Timestamp(...) parses it well (e.g. pd.Timestamp("2020-03") == pd.Timestamp('2020-03-01 00:00:00.000000')).

Thanks in advance!

EDIT: It seems that the internal function pandas._libs.tslibs.parsing.parse_datetime_string_with_reso returns what I want. Does anyone know how can I access it (not accessible using from pandas._libs.tslibs.parsing import parse_datetime_string_with_reso)?

CodePudding user response：

Addressing specifically this section of the question:

EDIT: It seems that the internal function pandas._libs.tslibs.parsing.parse_datetime_string_with_reso returns what I want. Does anyone know how can I access it (not accessible using from pandas._libs.tslibs.parsing import parse_datetime_string_with_reso)?

You can use from pandas._libs.tslibs.parsing import parse_time_string which internally calls parse_datetime_string_with_reso and also returns the resolution.

CodePudding user response：

dateutil has a good parser that allows the input string to have missing parts:

from dateutil import parser


dates = ["2021-01-06 12", "2020-03", "2020-03-01"]

for date in dates:
    if len(date.split('-')) <= 2:
        # If day is missing, resulting day will be the same as
        # the current day of month instead of '01'.
        date  = '-01'
    parsed = parser.parse(date)
    print(parsed)

output:

2021-01-06 12:00:00
2020-03-01 00:00:00
2020-03-01 00:00:00

CodePudding user response：

You can try this https://pypi.org/project/datefinder/ A python module for locating dates inside string.