More documents about example

Author: kngwyu

README.md

@@ -81,7 +81,9 @@ fn main() -> PyResult<()> {
 
 ### Write a Python module in Rust
 
-Please see the [examples](https://github.com/PyO3/rust-numpy/examples) directory for a complete example
+Please see [simple-extension](https://github.com/PyO3/rust-numpy/tree/master/examples/simple-extension)
+directory for the complete example.
+Also, we have an example project with [ndarray-linalg](https://github.com/PyO3/rust-numpy/tree/master/examples/linalg).
 
 ```toml
 [lib]
@@ -139,7 +141,11 @@ fn rust_ext(_py: Python<'_>, m: &PyModule) -> PyResult<()> {
 }
 ```
 
-## Contribution
-We need your feedback.
+## Conributing
+We welcome [issues](https://github.com/rust-numpy/rust-numpy/issues)
+and [pull requests](https://github.com/rust-numpy/rust-numpy/pulls).
+
+PyO3's [contrinbuting.md](https://github.com/PyO3/pyo3/blob/master/Contributing.md)
+is a nice guide for starting.
+Also, we have a [gitter](https://gitter.im/PyO3/Lobby) channel for communicating.
 
-Don't hesitate to open [issues](https://github.com/rust-numpy/rust-numpy/issues)!

examples/linalg/README.md

@@ -0,0 +1,9 @@
+# rust-numpy example extension with linalg
+
+An example extension with [ndarray-linalg](https://github.com/rust-ndarray/ndarray-linalg).
+
+Needs a fortran compiler (e.g., `gfortran`) for building.
+
+See [simple-extension's README](https://github.com/PyO3/rust-numpy/blob/master/examples/simple-extension/README.md)
+for introduction.
+

examples/simple-extension/README.md

@@ -1,26 +1,24 @@
-Example of rust-numpy
-----------------------
+# rust-numpy example extension
 
-- Prerequirement
+Here, we use [`maturin`][maturin] for building Python wheel and
+[`poetry`][poetry] for managing Python dependencies and virtualenvs.
+Following commands creates a virtualenv, install Python-side
+dependencies, and install the extension to the virtualenv.
 
+```bash
+poetry install
+poetry run maturin develop
 ```
-sudo pip3 install -r requirements.txt
-```
-
-- Build
 
-```
-python3 setup.py develop --user
-```
-
-- Run
+Once the extension installed, you can run the extension from
+Python REPL started by `poetry run python`:
 
 ```python
-import numpy as np
-import rust_ext
-
-a = np.array([0.0, 1.0])
-b = np.array([2.0, 3.0])
-rust_ext.axpy(2.0, a, b)
+>>> import numpy as np
+>>> import rust_ext
+>>> rust_ext.axpy(2.0, np.array([0.0, 1.0]), np.array([2.0, 3.0]))
+array([2., 5.])
 ```
-which returns `array([2., 5.])`.
+
+[maturin]: https://github.com/PyO3/maturin
+[poetry]: https://python-poetry.org/