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# C:\home\eric\wrk\scipy\weave\examples>python functional.py
# desired: [2, 3, 4]
# actual: [2, 3, 4]
# actual2: [2, 3, 4]
# python speed: 0.039999961853
# SCXX speed: 0.0599999427795
# speed up: 0.666666666667
# c speed: 0.0200001001358
# speed up: 1.99998807913
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 22 "functional.py"
py::tuple args(1);
int N = seq.len();
py::list result(N);
for(int i = 0; i < N;i++)
{
args[0] = seq[i];
result[i] = func.call(args);
}
return_val = 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 40 "functional.py"
py::tuple args(1);
PyObject* py_args = (PyObject*)args;
py::list result(seq.len());
PyObject* py_result = (PyObject*)result;
PyObject* item = NULL;
PyObject* this_result = NULL;
int N = seq.len();
for(int i = 0; i < N;i++)
{
item = PyList_GET_ITEM(py_seq,i);
Py_INCREF(item);
PyTuple_SetItem(py_args,0,item);
this_result = PyEval_CallObject(py_func,py_args);
PyList_SetItem(py_result,i,this_result);
}
return_val = 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 'SCXX 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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