Tag: Python
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Getting the day of week with `dt.day_of_week` in Pandas
Use dt.day_of_week to get the day number from a Python Pandas datetime series. But is 0 Sunday or Monday? Or not used at all? Better: Use the day_name method: Good news: It returns a series of strings!Bad news: It’s 4x slower.
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Pandas .dt accessor: Extracting year, hour, and day_of_week
Want to grab a part of datetime value in a Python Pandas data frame column? Use “dt”: day_of_week returns an integer, where 0 is Monday and 6 is Sunday.
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pandas read_csv date parsing: Using the date_format keyword
Reading a CSV into Python Pandas, and parse_dates doesn’t recognize the format? Pass the date_format keyword arg: All strftime codes work!
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Pandas parse_dates: Reading CSV date columns as datetimes
Reading a CSV into Python Pandas, and want a column to be treated as datetime values? Use parse_dates: Bonus: The PyArrow engine often (not always) parses columns that look like dates.
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pd.to_datetime: Converting a pandas string column to datetimes
Want to take a Python Pandas series of strings, and get datetime values? Use pd.to_datetime: Notice: It’s not a method! It’s a top-level pd function. Specify a non-standard “format” with a strftime string:
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Parse ISO date strings in Python with datetime.fromisoformat
If a Python string contains an ISO-formatted date, skip strptime and use datetime.fromisoformat:
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Python strptime vs. strftime: Parsing versus formatting dates
Having a tough time remembering Python strptime vs. strftime? – The “p” (strptime) is for parsing, getting a datetime from a string– The “f” (strftime) is for formatting, getting a string from a datetime For help remembering the format codes, turn to https://www.strfti.me/ !
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Python string to datetime: Parsing dates with strptime
Want to parse a Python string into a datetime? Use strptime, passing (a) the string and (b) the date format specification: Both return datetime.datetime(2026, 4, 1, 0, 0)
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Python datetime formatting: Using strftime for date strings
Want to format a Python datetime as a string? Use strftime:
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Timezone-aware datetime objects in Python with zoneinfo
Want a Python datetime with a timezone? Use the “zoneinfo” module: Then pass it to the “tzinfo” keyword arg: