Fix README example

Author: kngwyu

README.md

@@ -45,37 +45,28 @@ numpy = "0.3"
 ``` rust
 extern crate numpy;
 extern crate pyo3;
-use numpy::{IntoPyResult, PyArray, ToPyArray};
-use pyo3::prelude::{pymodinit, PyModule, PyResult, Python};
-
-#[pymodinit]
-fn rust_ext(_py: Python, m: &PyModule) -> PyResult<()> {
-    // immutable example
-    fn axpy(a: f64, x: ArrayViewD<f64>, y: ArrayViewD<f64>) -> ArrayD<f64> {
-        a * &x + &y
-    }
-
-    // mutable example (no return)
-    fn mult(a: f64, mut x: ArrayViewMutD<f64>) {
-        x *= a;
-    }
-
-    // wrapper of `axpy`
-    #[pyfn(m, "axpy")]
-    fn axpy_py(py: Python, a: f64, x: &PyArray<f64>, y: &PyArray<f64>) -> PyResult<PyArray<f64>> {
-        let x = x.as_array().into_pyresult("x must be f64 array")?;
-        let y = y.as_array().into_pyresult("y must be f64 array")?;
-        Ok(axpy(a, x, y).to_pyarray(py).to_owned(py))
-    }
-
-    // wrapper of `mult`
-    #[pyfn(m, "mult")]
-    fn mult_py(_py: Python, a: f64, x: &PyArray<f64>) -> PyResult<()> {
-        let x = x.as_array_mut().into_pyresult("x must be f64 array")?;
-        mult(a, x);
-        Ok(())
-    }
+use numpy::{IntoPyResult, PyArray, get_array_module};
+use pyo3::prelude::{ObjectProtocol, PyDict, PyResult, Python};
+
+fn main() -> Result<(), ()> {
+    let gil = Python::acquire_gil();
+    main_(gil.python()).map_err(|e| {
+        eprintln!("error! :{:?}", e);
+        // we can't display python error type via ::std::fmt::Display
+        // so print error here manually
+        e.print_and_set_sys_last_vars(gil.python());
+    })
+}
 
+fn main_<'py>(py: Python<'py>) -> PyResult<()> {
+    let np = get_array_module(py)?;
+    let dict = PyDict::new(py);
+    dict.set_item("np", np)?;
+    let pyarray: &PyArray<i32> = py
+        .eval("np.array([1, 2, 3], dtype='int32')", Some(&dict), None)?
+        .extract()?;
+    let slice = pyarray.as_slice().into_pyresult("Array Cast failed")?;
+    assert_eq!(slice, &[1, 2, 3]);
     Ok(())
 }
 ```
@@ -91,7 +82,7 @@ crate-type = ["cdylib"]
 
 [dependencies]
 numpy = "0.3"
-ndarray = "0.11"
+ndarray = "0.12"
 
 [dependencies.pyo3]
 version = "^0.4.1"
@@ -104,7 +95,7 @@ extern crate numpy;
 extern crate pyo3;
 
 use ndarray::{ArrayD, ArrayViewD, ArrayViewMutD};
-use numpy::{IntoPyArray, IntoPyResult, PyArray};
+use numpy::{IntoPyResult, PyArray, ToPyArray};
 use pyo3::prelude::{pymodinit, PyModule, PyResult, Python};
 
 #[pymodinit]
@@ -124,7 +115,7 @@ fn rust_ext(_py: Python, m: &PyModule) -> PyResult<()> {
     fn axpy_py(py: Python, a: f64, x: &PyArray<f64>, y: &PyArray<f64>) -> PyResult<PyArray<f64>> {
         let x = x.as_array().into_pyresult("x must be f64 array")?;
         let y = y.as_array().into_pyresult("y must be f64 array")?;
-        Ok(axpy(a, x, y).into_pyarray(py).to_owned(py))
+        Ok(axpy(a, x, y).to_pyarray(py).to_owned(py))
     }
 
     // wrapper of `mult`