> For the complete documentation index, see [llms.txt](https://docs.openbrim.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.openbrim.org/developers/paramml-developer-guide/core-objects/base-core-object/repeat.md).
# Repeat
Sometimes a certain part of an object's code may need to be repeated many times. Even the number of repetitions may be required to be determined by the user. In short, the **Repeat Object** is used to clone a series of objects multiple times.
Many structures consist of repetitions of structural components. For example;\
Multiple beams with different bracing locations in a bridge.\
Multiple stem rigidity bars in a bridge.\
Multiple panels for one tower.\
Multiple floors for one building.\
A previously defined content can be placed in the Repeat Object and cloned and positioned at certain geometric intervals. Any content inside the Repeat object is repeated as many times as the specified parameter.
All Repeat Objects must contain the following parameters:
* S (start)
* E (end)
* I (increment)
* CTRL (control parameter)
**Syntax**
```
...
...
```
**Example**
```xml
```
The above codes give exactly the same results as below.  To view this example in the library, see ( )
**Example:**
```xml
```
In the example provided, a 3D column object of type line is created and placed within a Repeat loop. The loop, with a starting number of 1, an ending number of 4, and incrementing by one each time, iterates 4 times, resulting in the creation of 4 identical column objects. This process results in the following system as output.  To view this example in the library, see ( )
The Repeat Object also allows for counting elements in a list and separating them as needed. This can be useful in situations where specific elements within the list need to be grouped or separated based on certain criteria.
**Example:**
```xml
```
In the above example, there are two nested repeat objects. In these objects, when it gets i=0 first, the object inside will repeat from j=0 to j=4 5 times and clone the 3D object within 5 of them.
Later, when the inside repetitions are completed, i = 1 will be and the inside object will be 5 again and will be created once.
Thus, as each i value increases, the j value will increase 5 times. This will continue until the outermost repeat count is completed and the following 3D object will be created.  To view this example in the library, see ()
ParamML is a programming language that employs lazy evaluation ( ), where each parameter is only computed when it is called. Unlike sequential programming (e.g., ), where each line is executed one by one, ParamML doesn't compute every parameter upfront. However, a drawback is that if a parameter is called a thousand times, it needs to be computed a thousand times, which can be a significant performance issue.
To address this problem, caching is used ( )."Repeat" is a specific object, and under normal circumstances, due to software limitations, we cannot employ caching within "repeat." This is where "StaticParams" comes into play. StaticParams overrides this rule. The parameters written within StaticParams are computed, and their values are manually added to the cache. As a result, when attempting to access these parameters within "repeat," there is no need to reevaluate the parameters; their values are readily available in the cache.
**Example:**
```
```
To view this example in the library, see ( )
### Parameters of Repeat Object
| **Label** | **Mandatory** | **Name and Type Attributes** | **Default Description and Value Attributes** | **Other Attributes** |
| ---------------- | ------------- | ---------------------------- | ------------------------------------------------------------------------------------------------------------------- | -------------------- |
| Control Variable | Yes | N="CTRL" T="Text" | D="Control Variable: The name of the variable that holds the repeat number as the contained objects repeated."V="0" | Role="Input" |
| Start | Yes | N="S" | D="Start: Starting repeat number (default 0)" V="0" | Role="Input" |
| End | Yes | N="E" | D="End: Ending repeat number (default 9)"V="0" | Role="Input" |
| Increment | | | | |
(Each Step) | Yes | N="I" | D="Increment: Increment used to go from start to end (default 1)"V="0" | Role="Input" | | StaticParams | No | N=”StaticParams” | D=”Parameter list which are used in repeat iterations but no need to calculate at each step” | Role="Input" |
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