Add pure Python version

Author: gjbex

source-code/cython/Structures/.gitignore

@@ -0,0 +1,2 @@
+point_cython.c
+point_pure.c

source-code/cython/Structures/Makefile

@@ -1,11 +1,16 @@
-VERSION = cpython-34m
-POINT_LIB = point.$(VERSION).so
+VERSION = cpython-311-x86_64-linux-gnu
+CYTHON_LIB = point_cython.$(VERSION).so
+PURE_LIB = point_pure.$(VERSION).so
 
-all: $(POINT_LIB)
+all: $(CYTHON_LIB) $(PURE_LIB)
 
-$(POINT_LIB): point.pyx
+$(CYTHON_LIB): point_cython.pyx
+	python setup.py build_ext --inplace
+
+$(PURE_LIB): point_pure.py
 	python setup.py build_ext --inplace
 
 clean:
 	python setup.py clean
-	rm -f point.c $(POINT_LIB)
+	$(RM) point_cython.c point_pure.c $(CYTHON_LIB) $(PURE_LIB)
+	$(RM) -r build

source-code/cython/Structures/README.md

@@ -0,0 +1,17 @@
+# Structues
+
+It is easy to define structures in Cython and pure Python
+syntax.
+
+
+## What is it?
+
+1. `point_cython.pyx`: Cython file that defines structure and
+   some functions that use this structure.
+1. `point_pure.py`: pure Python file that defines structure and
+   some functions that use this structure.
+1. `setup.py`: Python setup file to build the Cython extensions.
+1. `Makefile`: make file to build the Cython extensions.
+1. `driver.py`: Python script to illustrate the use of the
+   structure type, either the Cython or the pure Python version
+   can be selected.

source-code/cython/Structures/driver.py

@@ -1,6 +1,16 @@
 #!/usr/bin/env python
 
-import point
+import argparse
+
+arg_parser = argparse.ArgumentParser(description='Driver for point modules')
+arg_parser.add_argument('module', choices=['cython', 'pure_python'],
+                        help='module to use')
+options = arg_parser.parse_args()
+
+if options.module == 'cython':
+    import point_cython as point
+elif options.module == 'pure_python':
+    import point_pure as point
 
 p = point.create(1.0, -2.0, 1)
 print(p)

source-code/cython/Structures/point.pyx renamed to source-code/cython/Structures/point_cython.pyx

@@ -0,0 +1,27 @@
+import cython
+import math
+
+Point = cython.struct(
+    x=cython.double,
+    y=cython.double,
+    id=cython.int
+)
+
+def create(x: cython.double, y: cython.double,  id: cython.int) -> Point:
+    point: Point
+    point.x = x
+    point.y = y
+    point.id = id
+    return point
+
+def radius(point: Point) -> cython.double:
+    return math.sqrt(point.x**2 + point.y**2)
+
+def azimuth(point: Point) -> cython.double:
+    return math.atan2(point.y, point.x)
+
+def project(point: Point) -> None:
+    r: cython.double = radius(point)
+    point.x /= r
+    point.y /= r
+    print(point)

source-code/cython/Structures/point_pure.py

@@ -4,5 +4,6 @@
 from Cython.Build import cythonize
 
 setup(
-    ext_modules=cythonize("point.pyx")
+    ext_modules=cythonize(['point_cython.pyx', 'point_pure.py'],
+                          language_level='3str')
 )