update README with examples

Author: GregHanson

README.md

@@ -3,5 +3,58 @@ CLI tool for converting XML to RDF
 
 This Rust-based tool converts XML data into RDF format, utilizing the `oxrdf` crate for RDF graph handling and `xml-rs` for efficient XML parsing. Generated triples can either be added to an `oxrdf::Graph` or written directly to file.
 
+## Using the xml2rdf CLI
+
+This library includes a CLI utility for parsing XML and generating N-Triple RDF using the `convert` subcommand. The binary can be built using `cargo build`.
+
+```bash
+$ xml2rdf convert --help
+Convert XML to RDF format.
+
+The `convert` command parses a XML file, converts it to RDF triples using `xml-rs` for parsing and `oxrdf` to construct the graph, and saves the output.
+
+Usage: xml2rdf convert [OPTIONS]
+
+Options:
+  -n, --namespace <NAMESPACE>
+          Namespace for RDF graph generation.
+
+          A custom namespace to prefix RDF resources created from XML keys and values.
+
+          [default: https://decisym.ai/xml2rdf/data]
+
+  -x, --xml <XML>...
+          Path to input XML file(s).
+
+          Provide the path to one or more XML files that will be parsed and converted.
+
+  -o, --output-file <OUTPUT_FILE>
+          Path to output file.
+
+          Optional: Specify the path to save the generated RDF data. If not provided, data will be written to stdout
+
+  -h, --help
+          Print help (see a summary with '-h')
+```
+
+## Using the convert library
+
+The conversion functionality can also be called directly in Rust. The library supports writing results to a file or building an in-memory `oxrdf::Graph`.
+
+```rust
+use xml2rdf::convert::parse_xml;
+use xml2rdf::writer;
+use oxrdf::Graph;
+
+// capture conversion results to file
+let mut w = writer::FileWriter::to_file("output.nt".to_string()).unwrap();
+parse_xml(vec!["data.xml".to_string()], &mut w, "https://decisym.ai/xml2rdf/data");
+
+// capture conversion results to an oxrdf::Graph
+let mut g = Graph::new();
+let mut w = writer::GraphWriter::new(&mut g);
+parse_xml(vec!["data.xml".to_string()], &mut w, "https://decisym.ai/xml2rdf/data");
+```
+
 ## License
 This project is licensed under the BSD 3-Clause License - see the [LICENSE](LICENSE) file for details.