# inlunarweek Script and chart function
This function determines if timestamp lies inside the lunar week containing base\_date. Lunar weeks in Qlik Sense are defined by counting January 1 as the first day of the week., Apart from the final week of the year, each week will contain exactly seven days.
Syntax:
InLunarWeek (timestamp, base\_date, period\_no[, first\_week\_day])
Return data type: Boolean
Information note
In Qlik Sense, the Boolean true value is represented by -1, and the false value is represented by 0.
The `inlunarweek()` function determines which lunar week the `base_date` falls into. It then returns a Boolean result once it has determined whether each timestamp value occurs during the same lunar week as the `base_date`.
Diagram of `inlunarweek()` function
Diagram of `inlunarweek()` function
Diagram of `inlunarweek()`inlunarweek() function 
## When to use inlunarweek
The `inlunarweek()` function returns a Boolean result. Typically, this type of function will be used as a condition in an IF expression. This would return an aggregation or calculation dependent on whether the date evaluated occurred during the lunar week in question.
For example, the `inlunarweek()` function can be used to identify all equipment manufactured in a particular lunar week.
Arguments
| Argument | Description |
| --- | --- |
| timestamp | The date that you want to compare with base\_date. |
| base\_date | Date that is used to evaluate the lunar week. |
| period\_no | The lunar
week can be offset by period\_no.
period\_no is an integer, where the
value 0 indicates the lunar week which contains base\_date.
Negative values in period\_no indicate
preceding lunar weeks and positive values indicate succeeding lunar weeks. |
| first\_week\_day | An offset that may be greater than or less than zero. This changes the beginning of the year by the specified number of days and/or fractions of
a day. |
Function examples
| Example | Result |
| --- | --- |
| `inlunarweek('01/12/2013', '01/14/2013',
0)` | Returns `TRUE`, since the value of `timestamp`, 01/12/2013, falls in the week 01/08/2013 to 01/14/2013. |
| `inlunarweek('01/12/2013', '01/07/2013',
0)` | Returns `FALSE`, since the `base_date` 01/07/2013 is in the lunar week defined as 01/01/2013 to 01/07/2013. |
| `inlunarweek('01/12/2013', '01/14/2013',
-1)` | Returns `FALSE`. Specifying a value of period\_no as -1 shifts the week to the previous week, 01/01/2013 to 01/07/2013. |
| `inlunarweek('01/07/2013', 01/14/2013',
-1)` | Returns `TRUE`. In comparison with the previous example, the `timestamp` is in the following week, after into account the shift backwards. |
| `inlunarweek('01/11/2006', '01/08/2006',
0, 3)` | Returns `FALSE`. Specifying a value of 3 for `first_week_day` means that the start of the year is calculated from 01/04/2013. Therefore, the value of `base`\_date falls in the first week, and the value of `timestamp` falls in the week 01/11/2013 to 01/17/2013. |
The `inlunarweek()` function is often used in combination with the following functions:
Related functions
| Function | Interaction |
| --- | --- |
| [lunarweekname Script and chart function](https://help.qlik.com/en-US/cloud-services/Subsystems/Hub/Content/Sense_Hub/Scripting/DateAndTimeFunctions/lunarweekname.htm) | This function is used to determine the lunar week number of the year in which an input date occurs. |
## Regional settings
Unless otherwise specified, the examples in this topic use the following date format: MM/DD/YYYY. The date format is specified in the `SET DateFormat` statement in your data load script. The default date formatting may be different in your system, due to your regional settings and other factors. You can change the formats in the examples below to suit your requirements. Or you can change the formats in your load script to match these examples. For more information, see [Modifying regional settings for applications and scripts](https://help.qlik.com/en-US/cloud-services/Subsystems/Hub/Content/Sense_Hub/Apps/regional-settings-in-apps.htm).
Default regional settings in applications are based on the user profile. These regional format settings are not related to the language displayed in the Qlik Cloud user interface. Qlik Cloud will be displayed in the same language as the browser you are using.
If you are an application creator, you can set the default region for applications you create. For more information, see [Setting your preferred regional settings for creating apps and scripts in Qlik Cloud Analytics](https://help.qlik.com/en-US/cloud-services/Subsystems/Hub/Content/Sense_Hub/UserInterface/Languages.htm#Setting).
## Example 1 - No additional arguments
#### Load script and results
Overview
Open the Data load editor and add the load script below to a new section.
The load script contains:
* A dataset of transactions for the month of January, which is loaded into a table called `Transactions`.
* The date field has been provided in the `DateFormat` system variable (MM/DD/YYYY) format.
Create a field, `in_lunar_week`, that determines whether the transactions took place in the same lunar week as January 10.
Load script
```
SET DateFormat='MM/DD/YYYY';
Transactions:
Load
*,
inlunarweek(date,'01/10/2022', 0) as in_lunar_week
;
Load
*
Inline
[
id,date,amount
8183,'1/5/2022',42.32
8184,'1/6/2022',68.22
8185,'1/7/2022',15.25
8186,'1/8/2022',25.26
8187,'1/9/2022',37.23
8188,'1/10/2022',37.23
8189,'1/11/2022',17.17
8190,'1/12/2022',88.27
8191,'1/13/2022',57.42
8192,'1/14/2022',53.80
8193,'1/15/2022',82.06
8194,'1/16/2022',87.21
8195,'1/17/2022',95.93
8196,'1/18/2022',45.89
8197,'1/19/2022',36.23
8198,'1/20/2022',25.66
8199,'1/21/2022',82.77
8200,'1/22/2022',69.98
8201,'1/23/2022',76.11
];
```
Results
Load the data and open a sheet. Create a new table and add these fields as dimensions:
* `date`
* `in_lunar_week`
Results table
| date | in\_lunar\_week |
| --- | --- |
| 1/5/2022 | 0 |
| 1/6/2022 | 0 |
| 1/7/2022 | 0 |
| 1/8/2022 | -1 |
| 1/9/2022 | -1 |
| 1/10/2022 | -1 |
| 1/11/2022 | -1 |
| 1/12/2022 | -1 |
| 1/13/2022 | -1 |
| 1/14/2022 | -1 |
| 1/15/2022 | 0 |
| 1/16/2022 | 0 |
| 1/17/2022 | 0 |
| 1/18/2022 | 0 |
| 1/19/2022 | 0 |
| 1/20/2022 | 0 |
| 1/21/2022 | 0 |
| 1/22/2022 | 0 |
| 1/23/2022 | 0 |
`inlunarweek()` function, basic example
`inlunarweek()` function, basic example
`inlunarweek()`inlunarweek() function, basic example 
The `in_lunar_week` field is created in the preceding load statement by using the `inlunarweek()` function, then passing the following as the function's arguments:
* The `date` field
* A hard-coded date for January 10 as the `base_date`
* A`period_no` of 0
Because lunar weeks begin on January 1, January 10 would fall in the lunar week that begins on January 8 and ends on January 14. Therefore, any transactions that occur between those two dates in January would return a Boolean value of `TRUE`. This is validated in the results table.
## Example 2 - period\_no
[](https://help.qlik.com/en-US/cloud-services/Subsystems/Hub/Content/Sense_Hub/Scripting/DateAndTimeFunctions/inlunarweek.htm)
#### Examples and results:
Overview
Open the Data load editor and add the load script below to a new section.
The load script contains:
* The same dataset and scenario as the first example.
* The date field has been provided in the `DateFormat` system variable (MM/DD/YYYY) format.
However, in this example, the task is to create a field, `2_lunar_weeks_later`, that determines whether or not the transactions took place two lunar weeks after January 10.
Load script
```
SET DateFormat='MM/DD/YYYY';
Transactions:
Load
*,
inlunarweek(date,'01/10/2022', 2) as [2_lunar_weeks_later]
;
Load
*
Inline
[
id,date,amount
8183,'1/5/2022',42.32
8184,'1/6/2022',68.22
8185,'1/7/2022',15.25
8186,'1/8/2022',25.26
8187,'1/9/2022',37.23
8188,'1/10/2022',37.23
8189,'1/11/2022',17.17
8190,'1/12/2022',88.27
8191,'1/13/2022',57.42
8192,'1/14/2022',53.80
8193,'1/15/2022',82.06
8194,'1/16/2022',87.21
8195,'1/17/2022',95.93
8196,'1/18/2022',45.89
8197,'1/19/2022',36.23
8198,'1/20/2022',25.66
8199,'1/21/2022',82.77
8200,'1/22/2022',69.98
8201,'1/23/2022',76.11
];
```
Results
Load the data and open a sheet. Create a new table and add these fields as dimensions:
* `date`
* `2_lunar_weeks_later`
Results table
| date | 2\_lunar\_weeks\_later |
| --- | --- |
| 1/5/2022 | 0 |
| 1/6/2022 | 0 |
| 1/7/2022 | 0 |
| 1/8/2022 | 0 |
| 1/9/2022 | 0 |
| 1/10/2022 | 0 |
| 1/11/2022 | 0 |
| 1/12/2022 | 0 |
| 1/13/2022 | 0 |
| 1/14/2022 | 0 |
| 1/15/2022 | 0 |
| 1/16/2022 | 0 |
| 1/17/2022 | 0 |
| 1/18/2022 | 0 |
| 1/19/2022 | 0 |
| 1/20/2022 | 0 |
| 1/21/2022 | 0 |
| 1/22/2022 | -1 |
| 1/23/2022 | -1 |
`inlunarweek()` function, period\_no example
`inlunarweek()` function, period\_no example
`inlunarweek()`inlunarweek() function, period\_no example 
In this instance, because a `period_no` of 2 was used as the offset argument in the `inlunarweek()` function, the function defines the week beginning on January 22 as the lunar week to validate transactions against. Therefore, any transaction that takes place between the January 22 and January 28 will return a Boolean result of `TRUE`.
## Example 3 - first\_week\_day
[](https://help.qlik.com/en-US/cloud-services/Subsystems/Hub/Content/Sense_Hub/Scripting/DateAndTimeFunctions/inlunarweek.htm)
#### Load script and results
Overview
Open the Data load editor and add the load script below to a new tab.
The load script uses the same dataset and scenario as the first example. However, in the example, we set lunar weeks to begin on January 6.
* The same dataset and scenario as the first example.
* The default `DateFormat` system variable MM/DD/YYYY is used.
* A `first_week_day` argument of 5. This sets lunar weeks to begin on January 5.
Load script
```
SET DateFormat='MM/DD/YYYY';
Transactions:
Load
*,
inlunarweek(date,'01/10/2022', 0,5) as in_lunar_week
;
Load
*
Inline
[
id,date,amount
8183,'1/5/2022',42.32
8184,'1/6/2022',68.22
8185,'1/7/2022',15.25
8186,'1/8/2022',25.26
8187,'1/9/2022',37.23
8188,'1/10/2022',37.23
8189,'1/11/2022',17.17
8190,'1/12/2022',88.27
8191,'1/13/2022',57.42
8192,'1/14/2022',53.80
8193,'1/15/2022',82.06
8194,'1/16/2022',87.21
8195,'1/17/2022',95.93
8196,'1/18/2022',45.89
8197,'1/19/2022',36.23
8198,'1/20/2022',25.66
8199,'1/21/2022',82.77
8200,'1/22/2022',69.98
8201,'1/23/2022',76.11
];
```
Results
Load the data and open a sheet. Create a new table and add these fields as dimensions:
* `date`
* `in_lunar_week`
Results table
| date | in\_lunar\_week |
| --- | --- |
| 1/5/2022 | 0 |
| 1/6/2022 | -1 |
| 1/7/2022 | -1 |
| 1/8/2022 | -1 |
| 1/9/2022 | -1 |
| 1/10/2022 | -1 |
| 1/11/2022 | -1 |
| 1/12/2022 | -1 |
| 1/13/2022 | 0 |
| 1/14/2022 | 0 |
| 1/15/2022 | 0 |
| 1/16/2022 | 0 |
| 1/17/2022 | 0 |
| 1/18/2022 | 0 |
| 1/19/2022 | 0 |
| 1/20/2022 | 0 |
| 1/21/2022 | 0 |
| 1/22/2022 | 0 |
| 1/23/2022 | 0 |
`inlunarweek()` function, first\_week\_day example
`inlunarweek()` function, first\_week\_day example
`inlunarweek()`inlunarweek() function, first\_week\_day example 
In this instance, because the `first_week_date` argument of 5 is used in the `inlunarweek()` function, it offsets the start of the lunar week calendar to January 6. Therefore, January 10 falls in the lunar week beginning on January 6 and ending on January 12. Any transaction that falls between these two dates will return a Boolean value of `TRUE`.
## Example 4 - Chart object
[](https://help.qlik.com/en-US/cloud-services/Subsystems/Hub/Content/Sense_Hub/Scripting/DateAndTimeFunctions/inlunarweek.htm)
#### Load script and chart expression:
Overview
Open the Data load editor and add the load script below to a new section.
The load script contains:
* The same dataset and scenario as the first example.
* The date field has been provided in the DateFormat system variable (MM/DD/YYYY) format.
However, in this example, the unchanged dataset is loaded into the application. The calculation that determines whether the transactions took place in the same lunar week as January 10 is created as a measure in a chart object of the application.
Load script
```
SET DateFormat='MM/DD/YYYY';
Transactions:
Load
*
Inline
[
id,date,amount
8183,'1/5/2022',42.32
8184,'1/6/2022',68.22
8185,'1/7/2022',15.25
8186,'1/8/2022',25.26
8187,'1/9/2022',37.23
8188,'1/10/2022',37.23
8189,'1/11/2022',17.17
8190,'1/12/2022',88.27
8191,'1/13/2022',57.42
8192,'1/14/2022',53.80
8193,'1/15/2022',82.06
8194,'1/16/2022',87.21
8195,'1/17/2022',95.93
8196,'1/18/2022',45.89
8197,'1/19/2022',36.23
8198,'1/20/2022',25.66
8199,'1/21/2022',82.77
8200,'1/22/2022',69.98
8201,'1/23/2022',76.11
];
```
Results
Load the data and open a sheet. Create a new table and add this field as a dimension: date.
To calculate whether a transaction takes place in the lunar week that contains January 10, create the following measure:
= inlunarweek(date,'01/10/2022', 0)
Results table
| date | =inlunarweek(date,'01/10/2022', 0) |
| --- | --- |
| 1/5/2022 | 0 |
| 1/6/2022 | 0 |
| 1/7/2022 | 0 |
| 1/8/2022 | -1 |
| 1/9/2022 | -1 |
| 1/10/2022 | -1 |
| 1/11/2022 | -1 |
| 1/12/2022 | -1 |
| 1/13/2022 | -1 |
| 1/14/2022 | -1 |
| 1/15/2022 | 0 |
| 1/16/2022 | 0 |
| 1/17/2022 | 0 |
| 1/18/2022 | 0 |
| 1/19/2022 | 0 |
| 1/20/2022 | 0 |
| 1/21/2022 | 0 |
| 1/22/2022 | 0 |
| 1/23/2022 | 0 |
## Example 5 - Scenario
[](https://help.qlik.com/en-US/cloud-services/Subsystems/Hub/Content/Sense_Hub/Scripting/DateAndTimeFunctions/inlunarweek.htm)
#### Load script and chart expression:
Overview
Open the Data load editor and add the load script below to a new section.
The load script contains:
* A dataset which is loaded into a table called Products.
* Information consisting of product ID, manufacture date, and cost price.
It has been identified that due to equipment error, products that were manufactured in the lunar week that included January 12 were defective. The end user would like a chart object that displays, by lunar week name, the status of whether the products manufactured were ‘defective’ or ‘faultless’ and the cost of the products manufactured in that month.
Load script
```
SET DateFormat='MM/DD/YYYY';
Transactions:
Load
*
Inline
[
product_id,manufacture_date,cost_price
8183,'1/5/2022',42.32
8184,'1/6/2022',68.22
8185,'1/7/2022',15.25
8186,'1/8/2022',25.26
8187,'1/9/2022',37.23
8188,'1/10/2022',37.23
8189,'1/11/2022',17.17
8190,'1/12/2022',88.27
8191,'1/13/2022',57.42
8192,'1/14/2022',53.80
8193,'1/15/2022',82.06
8194,'1/16/2022',87.21
8195,'1/17/2022',95.93
8196,'1/18/2022',45.89
8197,'1/19/2022',36.23
8198,'1/20/2022',25.66
8199,'1/21/2022',82.77
8200,'1/22/2022',69.98
8201,'1/23/2022',76.11
];
```
Results
Do the following:
1. Load the data and open a sheet. Create a new table.
2. Create a dimension to show the month names:
=lunarweekname(manufacture\_date)
3. Create a measure to identify which of the products are defective and which are faultless using the inlunarweek() function:
=if(only(inlunarweek(manufacture\_date,makedate(2022,01,12),0)), 'Defective','Faultless')
4. Create a measure to sum the cost\_price of the products:
=sum(cost\_price)
5. Set the measure's Number formatting to Money.
6. Under Appearance, turn off Totals.
Results table
| lunarweekname(manufacture\_date) | =if(only(inlunarweek(manufacture\_date,makedate(2022,01,12),0)), 'Defective','Faultless') | sum(cost\_price) |
| --- | --- | --- |
| 2022/01 | Faultless | $125.79 |
| 2022/02 | Defective | $316.38 |
| 2022/03 | Faultless | $455.75 |
| 2022/04 | Faultless | $146.09 |
The inlunarweek() function returns a Boolean value when evaluating the manufacturing dates of each of the products. For any product manufactured in the lunar week that contains January 10, the inlunarweek() function returns a Boolean value of TRUE and marks the products as ‘Defective’. For any product returning a value of FALSE, and therefore not manufactured in that week, it marks the products as ‘Faultless’.