> For the complete documentation index, see [llms.txt](https://dev.ubidots.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://dev.ubidots.com/synthetic-variables.md).

# Synthetic variables

- [Getting started](https://dev.ubidots.com/synthetic-variables/getting-started.md)
- [Creating synthetic variables](https://dev.ubidots.com/synthetic-variables/getting-started/creating-synthetic-variables.md)
- [Synthetic variables' editor](https://dev.ubidots.com/synthetic-variables/getting-started/synthetic-variables-editor.md)
- [Expressions](https://dev.ubidots.com/synthetic-variables/expressions.md)
- [Mathematical](https://dev.ubidots.com/synthetic-variables/expressions/mathematical.md)
- [Date range](https://dev.ubidots.com/synthetic-variables/expressions/date-range.md): Ubidots lets you build new variables from time-series data over a date range. For example, you can calculate the mean, sum, or median per hour using a synthetic variable based on your sensor inputs.
- [Rolling](https://dev.ubidots.com/synthetic-variables/expressions/rolling.md): Compute a rolling value over a time window or number of values using mean, sum, min, max, or count.
- [Special functions](https://dev.ubidots.com/synthetic-variables/expressions/special-functions.md): Use functions to work with time series, fill gaps in missing data, write conditional statements, compute cumulative sums, and shift values in a series.
- [Specs and limits](https://dev.ubidots.com/synthetic-variables/specs-and-limits.md): Synthetic variables have the following limits for performance and the coding environment.
- [Examples](https://dev.ubidots.com/synthetic-variables/examples.md): Here are some examples of how to use synthetic variables and its functions.
- [Mathematical](https://dev.ubidots.com/synthetic-variables/examples/mathematical.md)
- [Date range](https://dev.ubidots.com/synthetic-variables/examples/date-range.md)
- [Rolling](https://dev.ubidots.com/synthetic-variables/examples/rolling.md)
- [Special functions](https://dev.ubidots.com/synthetic-variables/examples/special-functions.md)


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