I got a sample code and tested it but really can not understand the
use of pickle and dump: import pickle
f = open("try.txt", "w")
pickle.dump(3.1 4, f)
pickle.dump([1,2,3,4], f)
f.close()
4  2344 
On Mon, 2005-10-24 at 23:55 -0700, Shi Mu wrote: I got a sample code and tested it but really can not understand the
use of pickle and dump:
import pickle
f = open("try.txt", "w")
pickle.dump(3.1 4, f)
pickle.dump([1,2,3,4], f)
f.close()
The pickle module "serializes " python objects. You can "dump" a python
object that can later be loaded:
x = complex(2,3.5)
f = open("cnumber.p ickle", "w")
import pickle
pickle.dump(x, f)
f.close()
y = pickle.load(fil e("cnumber.pick le", "r"))
y
(2+3.5j)
what does the following code mean?
y = pickle.load(fil e("cnumber.pick le", "r"))
also, I can not understand "f" in pickle.dump(x, f)
On 10/25/05, marduk <us****@marduk. letterboxes.org > wrote: On Mon, 2005-10-24 at 23:55 -0700, Shi Mu wrote: I got a sample code and tested it but really can not understand the
use of pickle and dump:
>> import pickle
>> f = open("try.txt", "w")
>> pickle.dump(3.1 4, f)
>> pickle.dump([1,2,3,4], f)
>> f.close()
The pickle module "serializes " python objects. You can "dump" a python
object that can later be loaded:
x = complex(2,3.5)
f = open("cnumber.p ickle", "w")
import pickle
pickle.dump(x, f)
f.close()
y = pickle.load(fil e("cnumber.pick le", "r"))
y
(2+3.5j)
Shi Mu wrote: what does the following code mean?
y = pickle.load(fil e("cnumber.pick le", "r"))
open the file "cnumber.pickle " for reading, pass the file handle to
the pickle.load function, and store the result in the "y" variable.
also, I can not understand "f" in pickle.dump(x, f)
the second argument to pickle is a file handle, opened for writing.
pickle.dump will save the "pickled data" to that file.
</F>
Shi Mu wrote: what does the following code mean?
y = pickle.load(fil e("cnumber.pick le", "r"))
Take it by parts:
file("cnumber.p ickle", "r")
returns a file object as a result of opening the "cnumber.pickle " file,
which is presumably a pickle someone wrote earlier.
So
pickle.load(fil e("cnumber.pick le", "r"))
returns the first object stored in that pickle file.
also, I can not understand "f" in pickle.dump(x, f)
The beginning of the docs on pickle usage says:
"""dump( obj, file[, protocol[, bin]])
Write a pickled representation of obj to the open file object file."""
Isn't this reasopnably self-explanatory?
regards
Steve
[...]
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Holden Web LLC www.holdenweb.com
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