Original link: http://blog.csdn.net/cws1214/article/details/47984053
1. Avoid frequent redistribution
One of the most admirable features of STL containers is that they can automatically grow enough to accommodate the data you put in, as long as they are not larger than their maximum size. (To know the maximum value, just call the member function named Max_size.) )
For vectors and strings, if more space is needed, the size is increased by a similar realloc thought. This realloc-like operation ha
In practice, the vector series in c ++-C ++ 11 extends the vector member functions (cbegin (), cend (), crbegin (), crend (), and emplace (), data ())
The emplace_back mentioned above is added to C ++ 11.
Therefore, this blog just wants to list how C ++ 11 expands the vector container.
Std: vector: cbegin and std:
In practice, the vector series in c ++ -- copy set to vector (do not confuse reserve and resize)
The stl algorithm has a copy function. We can easily write this Code:
#include
#include #include
using namespace std;int _tmain(int argc, _TCHAR* argv[]){ double darray[10]={1.0,1.1,1.2,1.3,1.4,1.5,1.6,1.7,1.8,1.9}; vector
vdouble(10);
Vector or arraylist-which one is better? Why?
The answer to this question cannot be generalized. Sometimes it is better to use vector. Sometimes it is an arraylist. Sometimes neither of them is
The best choice. Don't expect a simple affirmative answer, because it depends on what you use them. Four of the following are to be considered:
Factors:
L API
L synchronous processing
L data growth
L usage mode
We wi
It is well known that SVM is a global optimal solution by solving a two-time programming problem, which leads to a lot of memory and time in practical applications. Most of the existing methods reduce support vectors by reducing training samples, which speeds up training. This article is from Li Qing and other paper "Support vector machine pre-selection based on vector projection".
The basic idea is that M
JDK source code-Vector, jdk-vector1, Vector:-1, an array of objects that can grow. Similar to an object array, it contains an integer index for component access. However, the Vector size can be increased or reduced as needed.-2. Each Vector optimizes storage management by maintaining capacity and capacityIncrement. Cap
Label: style blog HTTP color OS Io ar Div html When setting the CPU parameters during the learning process of the nioshi II, the Reset vector and exception vector settings are encountered. Shows the parameter setting screen. Reset vector -- Reset vectorException vector -- execution VectorFirst, it indicates that both
Vector applications (element traversal, insertion, deletion, switching, etc.), vectorHere is a summary of some common applications of vector containers. For the vector constructor and initialization, refer to http://blog.csdn.net/lsh_2013/article/details/21191289. Element Traversal
Use an iterator to access a vector El
Label: gradient descent method, cut vector, method Vector Zookeeper First, it indicates that the gradient is perpendicular to the cut vector of the curve, that is, the gradient direction is the direction of the normal vector: Set the curve x = x (t), Y = Y (T), and z = z (T) to the surface u (x, y, z) = a curve on C (
mentioned. This is the function interval.
Description :A: Taking two-dimensional space as an example, the linear equation is changed to +c=0 ax+by+c=0.
The usage vector w instead (A, b) is represented by the feature vector x, which is the formula.B: For the straight line we learned. By substituting the negative instance point (0,0), we can see that the calculated result +1 is inconsistent with
STD: Difference Between Reserve and resize of Vector1. Reserve: Allocate space, change capacity but not size2.Resize: Allocate space. Changing the capacity also changes the size.
If you know the vector size, resize it as an array without allocating extra memory.
ReserveIt is a container reserved space, but does not actually create element objects. Before creating an object, you cannot reference the elements in the container. Therefore, when add
There is a copy function in the STL algorithm. We can easily write this code:#include #include #include using namespace STD;int_tmain (intARGC, _tchar* argv[]) {Doubledarray[Ten]={1.0,1.1,1.2,1.3,1.4,1.5,1.6,1.7,1.8,1.9}; vectordouble>Vdouble (Ten); vectordouble>:: Iterator Outputiterator=vdouble.begin (); Copy (darray,darray+Ten, Outputiterator); while(Outputiterator!=vdouble.end ()) {coutreturn 0;}So you want to use copy to set the to vector, so you
C ++ is based on the vector graphics library cairo graphics, vector graphics cairo
// Sudo apt-get install libcairo2-dev // pkg-config -- cflags -- libs cairo //-I/usr/include/cairo-I/usr/include/glib-2.0-I /usr/lib/x86_64-linux-gnu/glib-2.0/include-I/usr/include/pixman-1-I/usr/include/freetype2-I/usr/include/libpng12-lcairo # include
Compilation in Ubuntu:
G ++ 'pkg-config -- cflags cairo 'test_cairo.cpp
Vg.net topology diagram software is a. NET platform based vector Diagram development tool, can be widely used in including: electric power, military, coal, chemical, scientific research, energy and other monitoring software, workflow Designer, power, chemical, coal, industrial control configuration software, simulation, geographic information system, workflow, complex report Industrial SCADA System, ERP process design system, graphic management, graph
650) this.width=650; "src=" Http://twaver.com.cn/Uploads/Product/vgnet/picture_designer_vs2005.png "style=" border : 0px;width:500px;height:400px; "/>650) this.width=650; "src=" Http://twaver.com.cn/Uploads/Product/vgnet/mixing_process_tank_reused.png "style=" border:0px;width:500px;height:400px; "/>Vg.net topology diagram software is a. NET platform based vector Diagram development tool, can be widely used in including: electric power, military, coal
Vg.net topology diagram software is a. NET platform based vector Diagram development tool, can be widely used in including: electric power, military, coal, chemical, scientific research, energy and other monitoring software, workflow Designer, power, chemical, coal, industrial control configuration software, simulation, geographic information system, workflow, complex report Industrial SCADA System, ERP process design system, graphic management, graph
In the Gaussian mixture model, I mentioned the general process of feature processing:
In fact, the Gaussian mixture model completes the task of K-means, then through the Gaussian mixture model clustering, also uses the general distance based method to carry On feature encoding. No, the Gaussian mixture model is usually used in conjunction with Fisher Vector. Now let's make a brief introduction to Fisher Vector
Dynamically assigned vector pointer Vector If it is a dynamically allocated vector pointer, you can only use the array method (the above Code is red) when inserting elements into the vector. the push_back () function has an error. Why? Use the shared_ptr vector point
Today, I have nothing to do with it. I 've been reading about it for a long time on my computer.
When I saw 43rd entries, I found that, as mentioned above, the algorithm replaces the manual loop.
No doubt arises.
I remember the operator [] operation (subscript operation) was the most efficient loop when I read the vector source code ).
The algorithm is fast.
The following is a test code:
// Test class and call Function
Class AAA{Public:Void MakeFul
C ++ Study Notes (15th): How the vector object grows in the memory space, learning notes vector
How does a vector object increase in memory?
We all know that vector objects are dynamically stored. From this point of view, they are a bit like linked lists, which can dynamically increase or decrease elements. We also kn
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