Hi,
I'm trying to initialize a set from a list but am unable to do so. My
list "c", looks like:
[(1.00909, 0.91969999999999996, -0.13550388182991072, 0),
(0.87423999999999991, 0.6666700000000001, -0.21230487137222254, 0)]
So basically a list of 2 tuples, each with 4 elements. Since tuples
are immutable, I think a set should be able to support them.
Anyway, I then do:
set_c = set(c)
And instead of getting a set, I get "None" when I try to print out
set_c. len(set_c) complains "TypeError: len() of unsized object."
Help?
Thank you.
4  4383 
Xiaolei Li wrote: Hi,
I'm trying to initialize a set from a list but am unable to do so. My
list "c", looks like:
[(1.00909, 0.91969999999999996, -0.13550388182991072, 0),
(0.87423999999999991, 0.6666700000000001, -0.21230487137222254, 0)]
So basically a list of 2 tuples, each with 4 elements. Since tuples
are immutable, I think a set should be able to support them.
Anyway, I then do:
set_c = set(c)
And instead of getting a set, I get "None" when I try to print out
set_c. len(set_c) complains "TypeError: len() of unsized object."
Help? c = [(1.00909, 0.91969999999999996, -0.13550388182991072, 0),
.... (0.87423999999999991, 0.6666700000000001, -0.21230487137222254, 0)] set_c = set(c)
set_c
set([(1.00909, 0.91969999999999996, -0.13550388182991072, 0),
(0.87423999999999991, 0.6666700000000001, -0.21230487137222254, 0)])
Please copy-and-paste the exact code that you wrote and the exact output.
--
Robert Kern
"I have come to believe that the whole world is an enigma, a harmless enigma
that is made terrible by our own mad attempt to interpret it as though it had
an underlying truth."
-- Umberto Eco
Robert Kern wrote: Xiaolei Li wrote: Hi,
I'm trying to initialize a set from a list but am unable to do so. My
list "c", looks like:
[(1.00909, 0.91969999999999996, -0.13550388182991072, 0),
(0.87423999999999991, 0.6666700000000001, -0.21230487137222254, 0)]
So basically a list of 2 tuples, each with 4 elements. Since tuples
are immutable, I think a set should be able to support them.
Anyway, I then do:
set_c = set(c)
And instead of getting a set, I get "None" when I try to print out
set_c. len(set_c) complains "TypeError: len() of unsized object."
Help?
c = [(1.00909, 0.91969999999999996, -0.13550388182991072, 0), ... (0.87423999999999991, 0.6666700000000001, -0.21230487137222254, 0)] set_c = set(c)
set_c set([(1.00909, 0.91969999999999996, -0.13550388182991072, 0),
(0.87423999999999991, 0.6666700000000001, -0.21230487137222254, 0)])
Please copy-and-paste the exact code that you wrote and the exact output.
Ok, I've basically found the cause of my problem. I'm including stuff
from pylab and that's causing some conflicts? Here's 6 lines of code:
from pylab import *
c = [1, 2, 3, 3]
print c
set_c = set(c)
print set
print set_c
When I run that (Python 2.4.2, Pylab 0.80), I get:
[1, 2, 3, 3]
<function set at 0xb751e1b4>
None
If I remove the first line, I correctly get:
[1, 2, 3, 3]
<type 'set'>
set([1, 2, 3])
Good news is that I didn't really need pylab in the program. So for
now, everything's working just fine.
Sybren Stuvel wrote: Xiaolei enlightened us with: from pylab import *
You'd better not do that. Just use "import pylab".
If I remove the first line, I correctly get:
[1, 2, 3, 3]
<type 'set'>
set([1, 2, 3])
Pylab shadows the built-in set name, which is one of the reasons you
should generally use "import XXX" instead of "from XXX import *".
Ahh. Understood. Thank you very much.
Xiaolei wrote: Sybren Stuvel wrote:
Xiaolei enlightened us with:
from pylab import *
You'd better not do that. Just use "import pylab".
If I remove the first line, I correctly get:
[1, 2, 3, 3]
<type 'set'>
set([1, 2, 3])
Pylab shadows the built-in set name, which is one of the reasons you
should generally use "import XXX" instead of "from XXX import *".
Ahh. Understood. Thank you very much.
It should be noted that recent versions of matplotlib's pylab module have
changed that function to setp() in order to avoid this problem.
--
Robert Kern
"I have come to believe that the whole world is an enigma, a harmless enigma
that is made terrible by our own mad attempt to interpret it as though it had
an underlying truth."
-- Umberto Eco This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics
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