cpython_numpy.md

Numpy Test

The Python script below is embedded in the final c++ exe, and run when cpython.initalize is called. The Mat class can then be used from Rusthon using the special -> syntax, that generates the required CPython C-API calls.

@embed

import numpy

class Mat():
	def __init__(self):
		self.lst = []
		self.v1  = numpy.array([1,2,3,4]).astype(int)
		self.v2  = numpy.array([0.01,0.002,0.0003,0.000004,0.00005,6.1]).astype(float)
	def show(self):
		print 'self.lst:', self.lst
		print 'self.v1:', self.v1
		print 'self.v2:', self.v2

Below, example loops over numpy arrays: v1 and v2, copies items from v1 to vec a c++11 std::vector and appends them to m->lst which is a normal Python array above self.lst.

Syntax for casting to Python Object types, X as PYTYPE, where PYTYPE can be:

• pyint
• pyi32
• pylong
• pyi64
• pyfloat
• pyf32
• pydouble
• pyf64
• pystring
• pybool

Build Options

• @link:python2.7
• @include:/usr/include/python2.7

#backend:c++
import cpython

def main():
	state = cpython.initalize()

	vec = []int()

	with gil:
		m = cpython.Mat()
		n1 = len(m->v1)
		n2 = len(m->v2)
		print 'length of vec1:', n1
		print 'length of vec2:', n2
		for i in range( len(m->v1) ):
			value = m->v1[i] as int
			print value
			vec.append(value)
			m->lst->append(i as pyint)
		m->show()
		for i in range( len(m->v2) ):
			a = m->v2[i] as float
			print a
			m->v2[i] = 3.14 as pyfloat
		m->show()

		for item as int in m->lst:
			print 'list item:', item

		m->lst->append("hello list" as pystring)
		m->lst->append(1.123456789 as pyfloat)
		m->lst->append( m )

		m->show()
		for something in m->lst:
			print pytype(something)
			print something->__class__->__name__ as string

			if ispyinstance(something, int):
				print 'item is a int'
				print something
			elif ispyinstance(something, str):
				print 'item is a string'
				print something
			elif ispyinstance(something, float):
				print 'item is a float'
				print something
			elif ispyinstance(something, Mat):
				print 'item is an instance of Mat'
				print something				
			else:
				print 'item is unknown some object'
				print something

	print 'length of vec copy:', len(vec)

	cpython.finalize(state)