Clip Analysis

Definition

The term Clip Analysis is one heavily used in Geographic Information Systems (GIS) software. Specifically, this technique involves taking the geometries from one layer and using them to cut, or "clip," the geometries from another layer. The result is a new layer that contains only the portions of the input layer's features that fall within the boundaries of the clipping layer.

What is Clip Analysis?

Clip Analysis is a standard geoprocessing tool that extracts features from one feature class that reside entirely within a specified area of another feature class. In GIS, the "clip" command is often used to study the overlap of multiple spatial features. Essentially, it creates a new dataset composed of the parts of features that are within the boundaries of the clipping features. The input features can be points, lines, or polygons, while the clipping features are always polygons. Use clip analysis when the study area is a smaller subset of the input features.

The clipping process involves a couple of steps. Firstly, a 'clip layer' is specified, which must have the same or lesser extent than the input layer. Next, the geographic features from the 'input layer' that fall within the extent of the clip layer are extracted and saved to a new layer. This resulting layer contains only the areas where the input layer and clip layer overlap.

FAQs

What types of data can be used for Clip Analysis?

Any type of geographic data – points, lines, or polygons – can be used as input data for clip analysis. However, the data that serves to define the boundaries, also known as clip features, must be polygon data.

How is Clip Analysis different from Intersect Analysis?

While both clip analysis and intersect analysis deal with the overlap of two datasets, they function differently. Clip Analysis only retains the portions of the input features within the clip features, while Intersect Analysis retains all overlapping parts of both features, creating a new output feature class that contains the spatially matched features of the input datasets.

What are practical applications of Clip Analysis?

Clip Analysis can be used in a variety of fields, including environmental science, urban planning, and transportation. For instance, it can be used to determine the parts of a city within a flood zone, to identify regions of agricultural activity within a specific geographical boundary, or to find out road networks within a specified area.

Can Clip Analysis be used with more than two layers at once?

Clip Analysis is primarily used with two layers: the input layer and the clip layer. However, using a sequence of clip operations or a combination of other GIS techniques, it can be used to analyze more complex scenarios involving multiple layers.