Tag Object: Difference between revisions

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== Example Flowgraph ==
== Example Flowgraph ==


Insert description of flowgraph here, then show a screenshot of the flowgraph and the output if there is an interesting GUI.  Currently we have no standard method of uploading the actual flowgraph to the wiki or git repo, unfortunately.  The plan is to have an example flowgraph showing how the block might be used, for every block, and the flowgraphs will live in the git repo.
[[File:Vector_source_with_tags.png]]


== Source Files ==
== Source Files ==

Latest revision as of 19:20, 29 November 2020

This block creates a tag object.

The tag objects are created using the python_to_tag Python function to make it easy to generate a tag_t in Python. The call looks like:

       gr.tag_utils.python_to_tag(($offset, $key, $value, $src))

Parameters

(R): Run-time adjustable

id (R)
ID of the tag, can be used to reference it in other blocks.
Offset (R)
While tags are based on an absolute offset, this is based on a relative offset that must be appropriately translated by the block using it. For example, this is used by the vector_source blocks, which will treat a 0 offset in the tag as the first item in the stream when the vector starts or repeats.
Key (R)
Name of the tag.
Value (R)
Value to give to the tag (can be a number, a boolean or a string).
Source ID (R)
Name of the source of the tag, is sometimes used by certain blocks.

Example Flowgraph

Vector source with tags.png

Source Files

C++ files
TODO
Header files
TODO
Public header files
TODO
Block definition
TODO