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Is there a foreach in MATLAB? If so, how does it behave if the underlying data changes?
...ropriate --- you'll be able to test the loop condition at every iteration, and set the value of the loop variable(s) as you wish:
n = 10;
f = n;
while n > 1
n = n-1;
f = f*n;
end
disp(['n! = ' num2str(f)])
Btw, the for-each loop in Java (and possibly other languages) produces unspecifi...
How to check if a function exists on a SQL database
...need to find out if a function exists on a database, so that I can drop it and create it again. It should basically be something like the following code that I use for stored procedures:
...
“Cloning” row or column vectors
... into a 2D array with length 1 in the first axis (vertical on your screen) and length 3 in the second axis (horizontal on your screen). Transposing then makes it have length 3 in the first axis and length 1 in the second axis. A tile shape of (1, 3) copies this column over three times, which is why ...
Choosing between std::map and std::unordered_map [duplicate]
...
It is very important to understand that for some applications, worst case performance is crucial to know and is the deciding factor. For some hard real-time systems, having a linear worst case like the hashtable is not acceptable. std::map is always O(lg N...
PHP 5: const vs static
In PHP 5, what is the difference between using const and static ?
7 Answers
7
...
What is the colon operator in Ruby?
...ifferent objects, even if they are equal content. == compares the content, and the equivalent checks with symbols are much faster.
user system total real
string 0.370000 0.000000 0.370000 ( 0.371700)
str == str 0.330000 0.000000 0.330000 ( 0.326368...
Remote debugging a Java application
...
Edit: I noticed that some people are cutting and pasting the invocation here. The answer I originally gave was relevant for the OP only. Here's a more modern invocation style (including using the more conventional port of 8000):
java -agentlib:jdwp=transport=dt_socket,...
How to initialize std::vector from C-style array?
...you just need a one time initialization, you can put it in the constructor and use the two iterator vector constructor:
Foo::Foo(double* w, int len) : w_(w, w + len) { }
Otherwise use assign as previously suggested:
void set_data(double* w, int len)
{
w_.assign(w, w + len);
}
...
How to change the output color of echo in Linux
I am trying to print a text in the terminal using echo command.
30 Answers
30
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LINGO使用指南 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...问题;
sets:
warehouses/wh1..wh6/: capacity;
vendors/v1..v8/: demand;
links(warehouses,vendors): cost, volume;
endsets
!目标函数;
min=@sum(links: cost*volume);
!需求约束;
@for(vendors(J):
@sum(warehouses(I): volume(I,J))=demand(J));
!产量约束;
@for(warehouses...