# LGF_GetCalendarWeek_US (FC / V3.0.1)

Author: Siemens Digital Industry

## Short description

This function uses the specified date to calculate the calendar week and the number of days that have passed since the beginning of the year for the USA and many other countries.

### Block Interface

| LGF_GetCalendarWeek_US (FC) |
--- | --- | ---
DTL |  |  | date |  | Ret_Val |  |  | DInt
|  |  |  |  | calendarDay |  |  | DInt
|  |  |  |  | error |  |  | Bool
|  |  |  |  | status |  |  | Word

### Input parameter

Identifier | Data type | Description
--- | --- | ---
date | DTL | Date used to calculate the calendar week and days since 1 January

### Output parameter

Identifier | Data type | Description
--- | --- | ---
Ret_Val | DInt | Number of the calendar week.
calendarDay | DInt | Days past since January 1st on given date
error | Bool | FALSE: No error / TRUE: An error occurred during the execution of the FB
status | Word | 16#0000-16#7FFF: Status of the FB / 16#8000-16#FFFF: Error identification (see following Table)

### Status & Error codes

Code / Value | Identifier / Description
--- | ---
16#0000 | STATUS_NO_ERROR Status: no error occurred
16#8201 | ERR_LIM_DATE Date out of the range, has to be greater than <1970-01-01 ; 2262-04-11>

## Functional description

Counting method for the USA and many other countries

- Calendar weeks have 7 days, start on a Sunday and are counted continuously throughout the year
- Calendar week 1 of a year is the week that contains January 1.
- Each year has either 52 or 53 calendar weeks.
- A year has 53 calendar weeks if the following characteristics apply:
  - A common year begins on a Saturday and ends on a Saturday.
  - A leap year begins either on a Saturday and ends on a Sunday or it begins on a Friday and ends on a Saturday.
- The days after the last Saturday in December can belong to the first calendar week of the following year.

## Change log

Version & Date | Change description
--- | ---
| 01.00.00 | Simatic Systems Support
| 13.11.2019 | First release based on spli from LGF_CalenderWeek (previously LGF_CalenderWeek_ISO)
| 03.00.00 | Simatic Systems Support
| 23.04.2020 | Set version to V3.0.0, harmonize the version of the whole library
| 03.00.01 | Simatic Systems Support
| 19.01.2020 | Insert documentation