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How do CDI and EJB compare? interact?
...llows you to inject implementation into your service or whatever. The main idea is that class, where you inject, should be managed by EJB container.
Seems that CDI does understand what EJB is, so in Java EE 6 compliant server, in your servlet you can write both
@EJB EJBService ejbService;
and
@Inje...
Android Fatal signal 11 (SIGSEGV) at 0x636f7d89 (code=1). How can it be tracked down?
...ther posts on tracking down the reasons for getting a SIGSEGV in an Android app. I plan to scour my app for possible NullPointers related to Canvas use, but my SIGSEGV barfs up a different memory address each time. Plus I've seen code=1 and code=2 . If the memory address was 0x00000000 , I'd...
Which kind of pointer do I use when?
...e rage. I never really looked into the other smart pointer types boost provided. I understand that C++11 now provides some of the types boost came up with, but not all of them.
...
What is pseudopolynomial time? How does it differ from polynomial time?
... when we start talking about algorithms that operate on numbers. Let's consider the problem of testing whether a number is prime or not. Given a number n, you can test if n is prime using the following algorithm:
function isPrime(n):
for i from 2 to n - 1:
if (n mod i) = 0, return false...
Why should we NOT use sys.setdefaultencoding(“utf-8”) in a py script?
... time, when Python scans the environment. It has to be called in a system-wide module, sitecustomize.py, After this module has been evaluated, the setdefaultencoding() function is removed from the sys module.
The only way to actually use it is with a reload hack that brings the attribute back.
A...
Why does X[Y] join of data.tables not allow a full outer join, or a left join?
...ifferent so change to be the same as `merge`
setcolorder(le, names(mallx))
identical(le, mallx)
# [1] TRUE
If you want a full outer join
# the unique values for the keys over both data sets
unique_keys <- unique(c(X[,t], Y[,t]))
Y[X[J(unique_keys)]]
## t b a
## 1: 1 NA 1
## 2: 2 NA 4
## ...
Equation (expression) parser with precedence?
... code like say, Aperture with GCC and they sell it without having to GPL said code).
Download Bison (or something equivalent, ANTLR, etc.).
There is usually some sample code that you can just run bison on and get your desired C code that demonstrates this four function calculator:
http://www.gnu....
Possible to make labels appear when hovering over a point in matplotlib?
...annot(ind)
annot.set_visible(True)
fig.canvas.draw_idle()
else:
if vis:
annot.set_visible(False)
fig.canvas.draw_idle()
fig.canvas.mpl_connect("motion_notify_event", hover)
plt.show()
Because people also want to use th...
Why do I have to access template base class members through the this pointer?
...se
int A;
#endif
static const int x = 2;
template <typename T> void foo() { A *x = 0; }
if A is a type, that declares a pointer (with no effect other than to shadow the global x). If A is an object, that's multiplication (and barring some operator overloading it's illegal, assigning to a...
What is the purpose of setting a key in data.table?
...two things:
reorders the rows of the data.table DT by the column(s) provided (a, b) by reference, always in increasing order.
marks those columns as key columns by setting an attribute called sorted to DT.
The reordering is both fast (due to data.table's internal radix sorting) and memory effic...