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import sys
sys.path.insert(0,'..')
import inline_tools
from types import *
def c_list_map(func,seq):
""" Uses CXX C code to implement a simple map-like function.
It does not provide any error checking.
"""
assert(type(func) in [FunctionType,MethodType,type(len)])
code = """
#line 12 "functional.py"
Py::Tuple args(1);
Py::List result(seq.length());
PyObject* this_result = NULL;
for(int i = 0; i < seq.length();i++)
{
args[0] = seq[i];
this_result = PyEval_CallObject(func,args.ptr());
result[i] = Py::Object(this_result);
}
return_val = Py::new_reference_to(result);
"""
return inline_tools.inline(code,['func','seq'])
def c_list_map2(func,seq):
""" Uses Python API more than CXX to implement a simple map-like function.
It does not provide any error checking.
"""
assert(type(func) in [FunctionType,MethodType,type(len)])
code = """
#line 32 "functional.py"
Py::Tuple args(1);
Py::List result(seq.length());
PyObject* item = NULL;
PyObject* this_result = NULL;
for(int i = 0; i < seq.length();i++)
{
item = PyList_GET_ITEM(seq.ptr(),i);
PyTuple_SetItem(args.ptr(),0,item);
this_result = PyEval_CallObject(func,args.ptr());
PyList_SetItem(result.ptr(),i,this_result);
}
return_val = Py::new_reference_to(result);
"""
return inline_tools.inline(code,['func','seq'])
def main():
seq = ['aa','bbb','cccc']
print 'desired:', map(len,seq)
print 'actual:', c_list_map(len,seq)
print 'actual2:', c_list_map2(len,seq)
def time_it(m,n):
import time
seq = ['aadasdf'] * n
t1 = time.time()
for i in range(m):
result = map(len,seq)
t2 = time.time()
py = t2 - t1
print 'python speed:', py
#load cache
result = c_list_map(len,seq)
t1 = time.time()
for i in range(m):
result = c_list_map(len,seq)
t2 = time.time()
c = t2-t1
print 'c speed:', c
print 'speed up:', py / c
#load cache
result = c_list_map2(len,seq)
t1 = time.time()
for i in range(m):
result = c_list_map2(len,seq)
t2 = time.time()
c = t2-t1
print 'c speed:', c
print 'speed up:', py / c
if __name__ == "__main__":
main()
time_it(100,1000)
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