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Difference in System. exit(0) , System.exit(-1), System.exit(1 ) in Java
...seful to know if something went wrong and what went wrong.
Exit code is
0 when execution went fine;
1, -1, whatever != 0 when some error occurred, you can use different values for different kind of errors.
If I'm correct exit codes used to be just positive numbers (I mean in UNIX) and according...
Check if all elements in a list are identical
..., for Python 2.7 and (only s1, s4, s7, s9 should return True)
s1 = [1] * 5000
s2 = [1] * 4999 + [2]
s3 = [2] + [1]*4999
s4 = [set([9])] * 5000
s5 = [set([9])] * 4999 + [set([10])]
s6 = [set([10])] + [set([9])] * 4999
s7 = [1,1]
s8 = [1,2]
s9 = []
we get
| checkEqual1 | checkEqual2 | checkE...
MySQL Update Inner Join tables query
I have no idea what the problem is. Using MySQL 5.0 I get a compile error when attempting to run the following MySQL update query:
...
How to pass optional arguments to a method in C++?
...e of passing mode as optional parameter
void myfunc(int blah, int mode = 0)
{
if (mode == 0)
do_something();
else
do_something_else();
}
you can call myfunc in both ways and both are valid
myfunc(10); // Mode will be set to default 0
myfunc(10, 1); // Mode will be ...
Python: Append item to list N times
...
For immutable data types:
l = [0] * 100
# [0, 0, 0, 0, 0, ...]
l = ['foo'] * 100
# ['foo', 'foo', 'foo', 'foo', ...]
For values that are stored by reference and you may wish to modify later (like sub-lists, or dicts):
l = [{} for x in range(100)]
(Th...
Iterating over a numpy array
...>>> for (x,y), value in numpy.ndenumerate(a):
... print x,y
...
0 0
0 1
1 0
1 1
2 0
2 1
Regarding the performance. It is a bit slower than a list comprehension.
X = np.zeros((100, 100, 100))
%timeit list([((i,j,k), X[i,j,k]) for i in range(X.shape[0]) for j in range(X.shape[1]) for k...
How to create a density plot in matplotlib?
... [4.5]*3 + [5.5]*1 + [6.5]*8
density = gaussian_kde(data)
xs = np.linspace(0,8,200)
density.covariance_factor = lambda : .25
density._compute_covariance()
plt.plot(xs,density(xs))
plt.show()
I get
which is pretty close to what you are getting from R. What have I done? gaussian_kde uses a changa...
How do I detect unsigned integer multiply overflow?
...lutions of a b = c , where a , b and c together use all the digits 0-9 exactly once. The program looped over values of a and b , and it ran a digit-counting routine each time on a , b and ab to check if the digits condition was satisfied.
...
Manifest merger failed : uses-sdk:minSdkVersion 14
...o not use dynamic updating.
compile 'com.android.support:support-v4:21.0.0'
}
fixed the issue.
Make sure you're not doing a general inclusion of com.android.support:support-v4:+ or any other support libraries (v7, v13, appcompat, etc), anywhere in your project.
I'd assume the problem is v4...
What is the order of precedence for CSS?
... TylerH
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answered Aug 3 '14 at 14:49
Lorenz MeyerLorenz Meyer
16.7k20...