FILTER functions (filtering functions) are used to get values from the table. Some functions enable additional filtering in a given table. These functions are often part of different functions as is nested parameter and enable dynamic calculations. They often serve as a value filter for function CALCULATE. Mostly it is the case of typical member of this category – FILTER function. For instance when we want to create metrics summing up values of some column but we need to limit the column based on some requirement = filter.
Script example representatives of DAX category function FILTER (function is named identically to the whole category). In the example of metrics is total sum of the sales > 1000
Sales USD > 1000 =
Sales[UnitCosts] * Sales[Quantity]
Sales[UnitPrice] * Sales[Quantity]
List of FILTER Functions in DAX Language for Power BI