It's been more than 3 years and I don't know if anyone has followed the
path since.
Today I had to retrieve J integer arrays from Python and I quickly wrote a
python script for doing that. It changes the J array into python lists(of
lists) with its shape. For example, i.3 3 is [[0, 1, 2], [3, 4, 5], [6, 7,
8]] in Python.
import operator
from ctypes import *
IDEN="jcmd_python"
def mulall(arr):
return reduce(operator.mul,arr,1)
def run_jcmd(js):
oledll.j.JDo(p,IDEN+'=:'+js)
def get_result(jdll,variable=IDEN):
pi=[pointer(c_int()) for _ in xrange(4)]
oledll.j.JGetM(jdll,variable,*pi) #datatype,rank, *shape, *value
type=pi[0].contents.value
if type==0: #error
return None,None,None,None
rank=pi[1].contents.value
shape=list((c_int*rank).from_address(pi[2].contents.value))
flat_size=mulall(shape)
data=list((c_int*flat_size).from_address(pi[3].contents.value))
return type,rank,shape,resize(shape,data)
def resize(shap,dat):
shap=shap[:]
flat_size=mulall(shap)
while len(shap)>1:
shd=[]
start=0
last_size=shap.pop()
while start<flat_size:
shd.append(dat[start:start+last_size])
start+=last_size
flat_size=len(shd)
dat=shd
else:
shd=dat
return shd
p=oledll.j.JInit()
run_jcmd("i. 3 3")
type,rank,shape,data=get_result(p) #returns the last result
print shape,data
run_jcmd("abc=: i: 5")
print get_result(p,"abc")
On Thu, Apr 29, 2010 at 12:43 AM, Richard Kubina <[email protected]> wrote:
> Thanks a lot, June! I will try to make some helper functions now and see
> if
> the python community takes any notice. It may be exciting for some folks
> to
> mesh Python lists and such with J (:
> ----------------------------------------------------------------------
> For information about J forums see http://www.jsoftware.com/forums.htm
>
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For information about J forums see http://www.jsoftware.com/forums.htm
