How to transfer python dict to CINT?

ROOT
1

I have some python scripts to read logs. I want to transfer the logs read from Python to CINT. Here are the detail story.

Data file (something like these):

# Gamma 1: E_γ = 0.847 MeV
# Gamma 1: E_γ = 1.238 MeV

C1C1-PH: [ 61, 272, 124], [273, 3840]
C1C2-PH: [ 79, 121,  88], [150, 3842], [1450.37, 6.33774], [2359.08, 5.25428], [3418.48, 4.87569]
C1C3-PH: [100, 128, 111], [250, 3833], [1478.59, 6.28460], [2392.18, 4.50688], [3457.03, 5.22970]

Python script to handle them:

def valid(a):
    if len(a)>0 and a[0] != "#": return True

def readrlog(fn):
    ss = [l.strip() for l in open(fn,"r").readlines()]
    records = {}
    for aa in filter(valid, ss):
        key,v = aa.split(":")
        try: records[key] = eval(v)
        except: print "Invalid record:",key,'--',v
    return records

logs = readrlog("myfile.log")

I want to use the result “logs” in CINT. How to implement this? TPythong::Bind(…)?
Please give me some hints. Thanks!

2

Hi,

instead of a python dict, create a dictionary for and use an std::mapstd::string,std::string (or: std.map(str,str) in python style) and pass that to CINT (see: http://root.cern.ch/root/html526/TPython.html for passing objects that have dictionaries associated with them).

Cheers,
Wim

3

It looks sophisticated. Python is good for handling dicts, lists, etc. If these data structures can be passed easily to CINT, it will be very charming.

4

Hi,

it probably wouldn’t be all that nice if python dicts could be passed. As said, you’d have a PyObject* on the CINT side. This object should then be manipulated with the Python C API, which isn’t all that pretty. The reason that dicts and lists are nice in python, is b/c the language supports it. They are not that nice in C++, as that language does not offer an equivalent support.

Cheers,
Wim