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How do I iterate over the words of a string?
...ction like this: f(split(s, d, v)) while still having the benefit of a pre-allocated vector if you like.
– Evan Teran
Jan 25 '14 at 17:50
8
...
Why does this code segfault on 64-bit architecture but work fine on 32-bit?
...o int* masks the fact that without the proper #include the return type of malloc is assumed to be int. IA-64 happens to have sizeof(int) < sizeof(int*) which makes this problem obvious.
(Note also that because of the undefined behaviour it could still fail even on a platform where sizeof(int)==...
How can I deploy an iPhone application from Xcode to a real iPhone device?
...w Run Script Build Phase. In the window, copy/paste this:
export CODESIGN_ALLOCATE=/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/codesign_allocate
if [ "${PLATFORM_NAME}" == "iphoneos" ]; then
/Developer/iphoneentitlements401/gen_entitlements.py "my.company.${PROJECT_NAME}" "${BUILT_PROD...
Fastest way to replace NAs in a large data.table
....805 12.301 134.985
system.time(a_andrie = f_andrie(dt1))
Error: cannot allocate vector of size 305.2 Mb
Timing stopped at: 14.541 7.764 68.285
system.time(f_dowle(dt1))
user system elapsed
7.452 4.144 19.590 # EDIT has faster than this
identical(a_gdata, dt1)
[1] TRUE
Note th...
Proper use of 'yield return'
... }
}
}
If you use List instead of yield, you will need to allocation 1 million objects to memory (~190mb) and this simple example will take ~1400ms to run. However, if you use yield, you don't need to put all these temp objects to memory and you will get significantly faster algori...
What are fixtures in programming?
...tate a method with @org.junit.After to release any permanent resources you allocated in setUp
For example, to write several test cases that want to work with different combinations of 12 Swiss Francs, 14 Swiss Francs, and 28 US Dollars, first create a fixture:
public class MoneyTest {
private M...
Performance differences between debug and release builds
...s is a big one, it makes property accessors essentially free.
CPU register allocation. Local variables and method arguments can stay stored in a CPU register without ever (or less frequently) being stored back to the stack frame. This is a big one, notable for making debugging optimized code so di...
private final static attribute vs private final attribute
...es, Java has no pass by reference anyways). A real useful test would be to allocate two objects and change the value of a public final int FOO = 10 variable using Java reflections in a forced way. Then check if the other object has also changed its value.
– Martijn Courteaux
...
How to truncate string using SQL server
...en outputting to a text file because only the new number of characters are allocated to that column in the output text file. (e.g. 50 instead of 1000) for more compact results.
– BillDarcy
Apr 15 '15 at 20:01
...
How do function pointers in C work?
...eir respective functions:
String newString()
{
String self = (String)malloc(sizeof(struct String_Struct));
self->get = &getString;
self->set = &setString;
self->length = &lengthString;
self->set(self, "");
return self;
}
For example, the getStrin...