# How to Write Filter Expressions

Filter expressions can include view-level filters where the variable refers to the entire view.

- filename ~ 'REJECT' // Returns views where filename contains 'REJECT'.
- count(feature) > 3 // Returns views with more than three features.

Filter expressions can also include axis filters, where the individual marking or labeling for each view is evaluated.

- feature [score > 0.5 ] // Returns views with a feature with score greater than 0.5.

You can combine view-level and axis-level filters.

- filename ~ 'REJECT' and feature [score > 0.5 ] // Returns views where filename contains 'REJECT' and a feature scoring greater than 0.5.

You can combine filters for multiple axes.

- feature [score > 0.5 ] and match [ score > 0.5 ] // Returns views with a feature with score greater than 0.5 and a match with a score greater than 0.5.

You can specify multiple filter conditions for an axis.

- feature[score > 0.5 and matched ] // Returns views with a feature with a score greater than 0.5 and the feature is in a matched model.