Pandas pd.Timestamp() Function
Commonly Used Pandas Functions
pd.Timestamp()is a function in the Pandas library forcreating timestamps.It can accept date-time input in multiple formats and return a precise Timestamp object.
Timestamp is a data type in Pandas used to represent a single point in time. It is an enhanced version of Python's standard library datetime.datetime, providing richer functionality and better performance.
Word Definition: TimestampMeans "timestamp", i.e., represents a specific moment in time.
Basic Syntax and Parameters
pd.Timestamp()is a top-level function of the Pandas library, used to create precise timestamp objects.
Syntax Format
pd.Timestamp(year=None, month=None, day=None, hour=None, minute=None, second=None, microsecond=None, nanosecond=None, tzinfo=None, freq=None) pd.Timestamp(value)
Parameter Description
| Parameter | Type | Required | Description | Default Value |
|---|---|---|---|---|
| value | String, datetime, int, float | Optional | The time value to convert. | None |
| year | Integer | Optional | Year (4 digits). | None |
| month | Integer | Optional | Month (1-12). | None |
| day | Integer | Optional | Day (1-31). | None |
| hour | Integer | Optional | Hour (0-23). | None |
| minute | Integer | Optional | Minute (0-59). | None |
| second | Integer | Optional | Second (0-59). | None |
| microsecond | Integer | Optional | Microsecond (0-999999). | None |
| nanosecond | Integer | Optional | Nanosecond (0-999999). | None |
| tz | String or tzinfo | Optional | Timezone information, e.g., 'UTC', 'Asia/Shanghai'. | None |
Return Value Description
- Return value: Returns a Timestamp object, similar to datetime.datetime.
- Effect: Converts time data in various formats to precise Pandas timestamps.
Examples
Let's thoroughly master, through a series of examples from simple to complex,pd.Timestamp()the usage of pd.Timestamp().
Example 1: Basic Usage - Creating Timestamps
Example
# 1. Create a timestamp using a string
print("=== Create Timestamp from String ===")
ts1 = pd.Timestamp('2023-01-01')
print(f"pd.Timestamp('2023-01-01'): {ts1}")
ts2 = pd.Timestamp('2023-01-01 12:30:45')
print(f"pd.Timestamp('2023-01-01 12:30:45'): {ts2}")
ts3 = pd.Timestamp('2023-05-15 08:00:00.123456')
print(f"With microseconds: {ts3}")
# 2. Create a timestamp using keyword arguments
print("\n=== Keyword Arguments Creation ===")
ts4 = pd.Timestamp(year=2023, month=6, day=15, hour=10, minute=30)
print(f"pd.Timestamp(year=2023, month=6, day=15, hour=10, minute=30): {ts4}")
# 3. Create from a datetime object
print("\n=== Create from datetime object ===")
import datetime
dt = datetime.datetime(2023, 8, 20, 14, 45, 30)
ts5 = pd.Timestamp(dt)
print(f"Created from datetime: {ts5}")
# 4. View timestamp attributes
print("\n=== Timestamp Attributes ===")
ts = pd.Timestamp('2023-03-15 10:30:45.123456')
print(f"Timestamp: {ts}")
print(f"Year: {ts.year}")
print(f"Month: {ts.month}")
print(f"Day: {ts.day}")
print(f"Hour: {ts.hour}")
print(f"Minute: {ts.minute}")
print(f"Second: {ts.second}")
print(f"Microsecond: {ts.microsecond}")
print(f"Day of week (0=Monday): {ts.dayofweek}")
print(f"Quarter: {ts.quarter}")
Output:
=== 字符串创建时间戳 ===
pd.Timestamp('2023-01-01'): 2023-01-01 00:00:00
pd.Timestamp('2023-01-01 12:30:45'): 2023-01-01 12:30:45
带微秒: 2023-05-15 08:00:00.123456
=== 关键字参数创建 ===
pd.Timestamp(year=2023, month=6, day=15, hour=10, minute=30): 2023-06-15 10:30:00
=== datetime 对象创建 ===
从 datetime 创建: 2023-08-20 14:45:30
=== 时间戳属性 ===
时间戳: 2023-03-15 10:30:45.123456
年份: 2023
月份: 3
日期: 15
小时: 10
分钟: 30
秒: 45
微秒: 123456
星期几 (0=周一): 2
季度: 1
Code analysis:
pd.Timestamp()It can accept input in multiple formats, including strings, datetime objects, etc.- Timestamp provides rich attributes to access various parts of the date and time.
dayofweekReturns 0-6, where 0 represents Monday.
Example 2: Timezone Handling
Example
# 1. Create a timestamp with a timezone
print("=== Create Timestamp with Timezone ===")
ts_utc = pd.Timestamp('2023-01-01 12:00:00', tz='UTC')
print(f"UTC timezone: {ts_utc}")
ts_shanghai = pd.Timestamp('2023-01-01 20:00:00', tz='Asia/Shanghai')
print(f"Shanghai timezone: {ts_shanghai}")
# 2. Conversion between different timezones
print("\n=== Timezone Conversion ===")
ts_utc = pd.Timestamp('2023-01-01 12:00:00', tz='UTC')
ts_local = ts_utc.tz_convert('Asia/Shanghai')
print(f"UTC time: {ts_utc}")
print(f"Converted to Shanghai: {ts_local}")
# 3. Create a local timezone timestamp (convert from naive to aware)
print("\n=== Convert Local Time to Timezone-aware ===")
ts_naive = pd.Timestamp('2023-01-01 12:00:00')
print(f"Naive (no timezone): {ts_naive}")
ts_aware = ts_naive.tz_localize('Asia/Shanghai')
print(f"Added Shanghai timezone: {ts_aware}")
# 4. Use shorthand forms of the tz parameter
print("\n=== Timezone Shorthand ===")
ts1 = pd.Timestamp('2023-01-01 12:00', tz='US/Eastern')
print(f"US Eastern: {ts1}")
ts2 = pd.Timestamp('2023-01-01 12:00', tz='Europe/London')
print(f"London: {ts2}")
Output:
=== 创建带时区的时间戳 === UTC 时区: 2023-01-01 12:00:00+00:00 上海时区: 2023-01-01 20:00:00+08:00 === 时区转换 === UTC 时间: 2023-01-01 12:00:00+00:00 转换到上海: 2023-01-01 20:00:00+08:00 === 本地时间转带时区 === 无时区: 2023-01-01 12:00:00 添加上海时区: 2023-01-01 12:00:00+08:00 === 时区简写 === 美国东部: 2023-01-01 12:00:00-05:00 伦敦: 2023-01-01 12:00:00+00:00
Code analysis:
tz_localizeUsed to add timezone information to a naive Timestamp.tz_convertUsed to convert between different timezones.
Example 3: Timestamp Comparison and Operations
Example
# 1. Timestamp comparison
print("=== Timestamp Comparison ===")
ts1 = pd.Timestamp('2023-01-01')
ts2 = pd.Timestamp('2023-01-15')
ts3 = pd.Timestamp('2023-01-01')
print(f"ts1: {ts1}")
print(f"ts2: {ts2}")
print(f"ts1 < ts2: {ts1 < ts2}")
print(f"ts1 == ts3: {ts1 == ts3}")
print(f"ts1 != ts2: {ts1 != ts2}")
# 2. Operations between Timestamp and Timedelta
print("\n=== Timestamp and Timedelta Operations ===")
ts = pd.Timestamp('2023-01-01 12:00:00')
td = pd.Timedelta(days=5, hours=3)
print(f"Original timestamp: {ts}")
print(f"Timedelta: {td}")
print(f"ts + td: {ts + td}")
print(f"ts - td: {ts - td}")
# 3. Subtract two timestamps to get a Timedelta
print("\n=== Subtracting Two Timestamps ===")
ts1 = pd.Timestamp('2023-01-15 18:00:00')
ts2 = pd.Timestamp('2023-01-10 09:00:00')
diff = ts1 - ts2
print(f"ts1: {ts1}")
print(f"ts2: {ts2}")
print(f"ts1 - ts2: {diff}")
print(f"Days: {diff.days}")
print(f"Hours: {diff.seconds / 3600}")
# 4. Use timestamps in DataFrame
print("\n=== Timestamps in DataFrame ===")
df = pd.DataFrame({
'event': ['event_a', 'event_b', 'event_c'],
'timestamp': [
pd.Timestamp('2023-01-01 10:00:00'),
pd.Timestamp('2023-01-02 15:30:00'),
pd.Timestamp('2023-01-03 09:45:00')
]
})
print(df)
print(f"\nEvent duration (relative to the first event):")
df['relative_days'] = (df['timestamp'] - df['timestamp'].iloc[0]).dt.days
print(df)
Output:
=== 时间戳比较 ===
ts1: 2023-01-01 00:00:00
ts2: 2023-01-15 00:00:00
ts1 < ts2: True
ts1 == ts3: True
ts1 != ts2: True
=== 时间戳与时间差运算 ===
原时间戳: 2023-01-01 12:00:00
时间差: 5 days 03:00:00
ts + td: 2023-01-06 15:00:00
ts - td: 2022-12-27 09:00:00
=== 两个时间戳相减 ===
ts1: 2023-01-15 18:00:00
ts2: 2023-01-10 09:00:00
ts1 - ts2: 5 days 09:00:00
天数: 5
小时: 9.0
=== DataFrame 中的时间戳 ===
event timestamp
0 event_a 2023-01-01 10:00:00
1 event_b 2023-01-02 15:30:00
2 event_c 2023-01-03 09:45:00
事件持续时间(相对于第一个事件):
event timestamp relative_days
0 event_a 2023-01-01 10:00:00 0
1 event_b 2023-01-02 15:30:00 1
2 event_c 2023-01-03 09:45:00 2
Code analysis:
- Timestamp supports direct comparison operators (>, <, ==, !=).
- Adding or subtracting a Timedelta to/from a Timestamp yields a new Timestamp or Timedelta.
- Subtracting two timestamps yields a Timedelta object.
- Time-related calculations can be conveniently performed in DataFrame.
Important Notes
Important note:
pd.TimestampSimilar to Python's datetime, but provides higher performance and more methods.- Timestamp objects are immutable; modification operations return new objects.
- Timezone information is best specified at creation time; modifying the timezone later may cause ambiguity.
- Use NaT
pd.NaT(Not a Time) to represent missing time values.
Other Extensions