Streams and Vectors

This tutorial will describe the difference between a Stream and a Vector. You can find the previous tutorial here: Converting Data Types

Streams

Streams in GNU Radio are what convey the information between blocks and are represented by the arrows connecting blocks in a flowgraph. A stream must have a data type, such as Float 32 or Byte. A stream carries 1 sample for each time instance and are used to represent and process serial data.

The Signal Source block produces a Complex Float 32 stream. The output of the block at each time instance contains 1 complex sample:

Vectors

Where streams carry 1 sample per time instance, vectors can carry multiple samples per time instance. By analogy, a stream represents a scalar at each time instance, whereas a vector represents an array at each time instance. Vectors allow data to be represent and process data in parallel.

darker color in GRC

• note: use an image