Turtle Writer Options
diff --git a/source/documentation/io/rdf-output.md b/source/documentation/io/rdf-output.md
index 21b269c..b425918 100644
--- a/source/documentation/io/rdf-output.md
+++ b/source/documentation/io/rdf-output.md
@@ -14,6 +14,7 @@
- [Pretty Printed Languages](#pretty-printed-languages)
- [Streamed Block Formats](#streamed-block-formats)
- [Line printed formats](#line-printed-formats)
+ - [Turtle and Trig format options](#opt-turtle-trig)
- [N-Triples and N-Quads](#n-triples-and-n-quads)
- [JSON-LD](#json-ld)
- [RDF Binary](#rdf-thrift)
@@ -24,7 +25,7 @@
See [Advanced RDF/XML Output](rdfxml_howto.html#advanced-rdfxml-output)
for details of the Jena RDF/XML writer.
-## API
+## API {#api}
There are two ways to write RDF data using Apache Jena RIOT,
either via the `RDFDataMgr`
@@ -43,7 +44,7 @@
Many variations of these methods exist. See the full javadoc for details.
-## `RDFFormat`
+## `RDFFormat` {#rdfformat}
Output using RIOT depends on the format, which involves both the language (syntax)
being written and the variant of that syntax.
@@ -204,7 +205,7 @@
| TURTLE_BLOCKS |
| TRIG_BLOCKS |
-### Line printed formats
+### Line printed formats {#line-printed-formats}
There are writers for Turtle and Trig that use the abbreviated formats for
prefix names and short forms for literals. They write each triple or quad
@@ -240,7 +241,58 @@
| TURTLE_FLAT |
| TRIG_FLAT |
-### N-Triples and N-Quads
+### Turtle and Trig format options {#opt-turtle-trig}
+
+Some context settings affect the output of Turtle and TriG writers. Unless
+otherwise noted, the setting applies to both Turtle and TriG.
+
+| Context setting | Cmd line | Values |
+|-----------------|----------|--|
+| RIOT.symTurtleDirectiveStyle | "ttl:directiveStyle" | "sparql", "rdf11", "at", "n3" |
+| RIOT.symTurtleOmitBase | "ttl:omitBase" | "true", "false" |
+
+<p> </p>
+
+| Directive Style | Effect |
+|------------------|-------|
+| "sparql", "rdf11" | Use `PREFIX` and `BASE` in output. |
+| "at", "n3" | Use `@prefix` and `@base` in output. |
+| unset | Use `@prefix` and `@base` in output. |
+
+<p> </b>
+
+#### Format Option Usage
+
+##### _Setting directive style_
+```
+ riot --set ttl:directiveStyle=sparql --pretty Turtle file1.rdf file2.nt ...
+```
+and in code:
+```
+ RDFWriter.create()
+ .set(RIOT.symTurtleDirectiveStyle, "sparql")
+ .lang(Lang.TTL)
+ .source(model)
+ .output(System.out);
+```
+##### _Base URI_
+
+Output can be written with relative URIs and no base. Note: such output is not
+portable; its meaning depends on the base URI at the time of reading.
+
+Turtle and Trig can be written with relative URIs by
+setting the base URI for writing and switching off output of the base URI.
+
+```
+ RDFWriter.create()
+ .base("http://host/someBase")
+ .set(RIOT.symTurtleOmitBase, true)
+ .lang(Lang.TTL)
+ .source(model)
+ .output(System.out);
+```
+
+### N-Triples and N-Quads {#n-triples-and-n-quads}
These provide the formats that are fastest to write,
and data of any size can be output. They do not use any
@@ -289,7 +341,7 @@
| NTRIPLES_ASCII |
| NQUADS_ASCII |
-### JSON-LD
+### JSON-LD {#json-ld}
JSON-LD output is supported, in its various flavors
("compacted", "expanded", "flattened", "framed"),
@@ -317,7 +369,7 @@
What can be done, and how it can be, is explained in the
[sample code](https://github.com/apache/jena/tree/master/jena-arq/src-examples/arq/examples/riot/Ex_WriteJsonLD.java).
-### RDF Binary
+### RDF Binary {#rdf-thrift}
[This is a binary encoding](rdf-binary.html) using
[Apache Thrift](https://thrift.apache.org/) for RDF Graphs
@@ -334,7 +386,7 @@
[description of RDF Thrift](http://afs.github.io/rdf-thrift)
for discussion.
-### RDF/XML
+### RDF/XML {#rdfxml}
RIOT supports output in RDF/XML. RIOT RDFFormats defaults to pretty printed RDF/XML,
while the jena writer name defaults to a streaming plain output.
@@ -344,7 +396,7 @@
| RDFXML | RDFXML_PRETTY, RDF_XML_ABBREV | "RDF/XML-ABBREV" |
| RDFXML_PLAIN | | "RDF/XML" |
-## Examples
+## Examples {#examples}
Example code may be found in [jena-arq/src-examples](https://github.com/apache/jena/tree/master/jena-arq/src-examples/arq/examples/riot/).
@@ -402,7 +454,7 @@
A complete example of adding a new output format is given in the example file:
[RIOT Output example 3](https://github.com/apache/jena/tree/master/jena-arq/src-examples/arq/examples/riot/ExRIOT_out3.java)
-## Notes
+## Notes {#notes}
Using `OutputStream`s is strongly encouraged. This allows the writers
to manage the character encoding using UTF-8. Using `java.io.Writer`
