Calculate Julian Day Number: Counting days since January 1, 4713 BC. Get the Julian Day Number for any date.

Calculate Julian Day Number

Purpose

The Calculate Julian Day Number function is used to determine the Julian Day Number, which is a system of counting days since a specific day (January 1, 4713 BC). This can be useful for historical or astronomical calculations.

Use Cases

• Calculate the Julian Day Number for a specific date.
• Convert dates to Julian Day Numbers for comparison or calculation purposes.

How to Use

1. Enter the date for which you want to calculate the Julian Day Number.
2. Click on the "Calculate" button to get the result.

Input Values

1. Date: Select the date for which you want to calculate the Julian Day Number. Default unit is the Gregorian calendar date.

Output Values

1. Julian Day Number: The calculated Julian Day Number for the input date. This value represents the number of days since January 1, 4713 BC.

Any other Instruction

• The Julian Day Number is a continuous count of days starting from January 1, 4713 BC. It is used in astronomy and historical calculations.

Code Analysis

1. The function takes a date as input and converts it to a timestamp.
2. It then calculates the Julian Day Number based on the timestamp and returns the result.

Technical Parameters

• on_date

Return Values

• Julian Day Number

Example Expressions

You can use the following expressions to directly evaluate in a non-interactive manner using eval():

jday(datetime.date(2022, 12, 31))
jday(datetime.date(2000, 1, 1))

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