Search Results

Search found 2562 results on 103 pages for 'vector'.

Page 11/103 | < Previous Page | 7 8 9 10 11 12 13 14 15 16 17 18  | Next Page >

• Is there a way to specify the dimensions of a nested STL vector C++?

  - by zebraman

  I know vectors can be constructed to a predefined size vector<int> foo(4); But is there a way to specify the dimensions of nested vectors? vector< vector<int> > bar(4); Lets say I wanted a vector of size 4 containing vector's of size 4... like a 4x4 multidimensional array of ints?

  Read the article

• iPhone/Mac - C++ vector or NSMutableArray

  - by satyam

  I'm creating an application for iPhone which needs to handle large data. So, I would like to know which one will be better to use : C++ Vectors or ObjectiveC's NSMutableArray? Which one will be faster to access elements, delete elements, add elements etc. Can some one guide me please?

  Read the article

• C# vector class - Interpolation design decision

  - by Benjamin

  Currently I'm working on a vector class in C# and now I'm coming to the point, where I've to figure out, how i want to implement the functions for interpolation between two vectors. At first I came up with implementing the functions directly into the vector class... public class Vector3D { public static Vector3D LinearInterpolate(Vector3D vector1, Vector3D vector2, double factor) { ... } public Vector3D LinearInterpolate(Vector3D other, double factor { ... } } (I always offer both: a static method with two vectors as parameters and one non-static, with only one vector as parameter) ...but then I got the idea to use extension methods (defined in a seperate class called "Interpolation" for example), since interpolation isn't really a thing only available for vectors. So this could be another solution: public class Vector3D { ... } public static class Interpolation { public static Vector3D LinearInterpolate(this Vector3D vector, Vector3D other, double factor) { ... } } So here an example how you'd use the different possibilities: { var vec1 = new Vector3D(5, 3, 1); var vec2 = new Vector3D(4, 2, 0); Vector3D vec3; vec3 = vec1.LinearInterpolate(vec2, 0.5); //1 vec3 = Vector3D.LinearInterpolate(vec1, vec2, 0.5); //2 //or with extension-methods vec3 = vec1.LinearInterpolate(vec2, 0.5); //3 (same as 1) vec3 = Interpolation.LinearInterpolation(vec1, vec2, 0.5); //4 } So I really don't know which design is better. Also I don't know if there's an ultimate rule for things like this or if it's just about what someone personally prefers. But I really would like to hear your opinions, what's better (and if possible why ).

  Read the article

• Client Side Prediction for a Look Vector

  - by Mike Sawayda

  So I am making a first person networked shooter. I am working on client-side prediction where I am predicting player position and look vectors client-side based on input messages received from the server. Right now I am only worried about the look vectors though. I am receiving the correct look vector from the server about 20 times per second and I am checking that against the look vector that I have client side. I want to interpolate the clients look vector towards the correct one that is server side over a period of time. Therefore no matter how far you are away from the servers look vector you will interpolate to it over the same amount of time. Ex. if you were 10 degrees off it would take the same amount of time as if you were 2 degrees off to be correctly lined up with the server copy. My code looks something like this but the problem is that the amount that you are changing the clients copy gets infinitesimally small so you will actually never reach the servers copy. This is because I am always calculating the difference and only moving by a percentage of that every frame. Does anyone have any suggestions on how to interpolate towards the servers copy correctly? if(rotationDiffY > ClientSideAttributes::minRotation) { if(serverRotY > clientRotY) { playerObjects[i]->collisionObject->rotation.y += (rotationDiffY * deltaTime); } else { playerObjects[i]->collisionObject->rotation.y -= (rotationDiffY deltaTime); } }

  Read the article

• Create and define Vector

  - by zdmytriv

  I'm looking for method to create Vector and push some values without defining variable Vector. For example: I have function: public function bla(data:Vector.<Object>):void { ... } this function expects Vector as parameter. I can pass parameters this way var newVector:Vector.<Object> = new Vector.<Object>(); newVector.push("bla1"); newVector.push("bla2"); bla(newVector); Can I do it in one line in Flex? I'm looking for something like: bla(new Vector.<Object>().push("bla1").push("bla2")); I've also tried this: bla(function():Vector.<Object> { var result:Vector.<Object> = new Vector.<Object>(2, true); result.push("bla1"); result.push("bla2"); return result; }); But it complains: 1067: Implicit coercion of a value of type Function to an unrelated type __AS3__.vec:Vector.<Object>... Thanks

  Read the article

• 2D vector value replacement using classes; genetic algorithm mutation

  - by gcolumbus

  I have a 2D vector as defined by the classes below. Note that I've used classes because I'm trying to program a genetic algorithm such that many, many 2D vectors will be created and they will all be different. class Quad: public std::vector<int> { public: Quad() : std::vector<int>(4,0) {} }; class QuadVec : public std::vector<Quad> { }; An important part of my algorithm, however, is that I need to be able to "mutate" (randomly change) particular values in a certain number of randomly chosen 2D vectors. This has me stumped. I can easily write code to randomly select the value within the 2D vector that will be selected for "mutation" but how do I actually enact that change using classes? I understand how this would be done with one 2D vector that has already been initialized but how do I do this if it hasn't? Please let me know if I haven't provided enough info or am not clear as I tend to do that. Thanks for your time and help!

  Read the article

• How to implement button in a vector

  - by user1880497

  In my table. I want to put some buttons into each row that I can press. But I do not know how to do it public static DefaultTableModel buildTableModel(ResultSet rs) throws SQLException { java.sql.ResultSetMetaData metaData = rs.getMetaData(); // names of columns Vector<String> columnNames = new Vector<String>(); int columnCount = metaData.getColumnCount(); for (int column = 1; column <= columnCount; column++) { columnNames.add(metaData.getColumnName(column)); } // data of the table Vector<Vector<Object>> data = new Vector<Vector<Object>>(); while (rs.next()) { Vector<Object> vector = new Vector<Object>(); for (int columnIndex = 1; columnIndex <= columnCount; columnIndex++) { vector.add(rs.getObject(columnIndex)); } data.add(vector); } return new DefaultTableModel(data, columnNames); }

  Read the article

• push_back private vectors with 2 methods, one isn't working

  - by jmclem

  I have a class with a private vector of doubles. To access or modify these values, at first I used methods such as void classA::pushVector(double i) { this->vector.push_back(i); } double classA::getVector(int i) { return vector[i]; } This worked for a while until I found I would have to overload a lot of operators for what I needed, so I tried to change it to get and set the vector directly instead of the values, i.e. void classA::setVector(vector<double> vector) { this->vector = vector; } vector<double> classA::getVector() { return vector; } Now, say there is a classB, which has a private classA element, which also has get and set methods to read and write. The problem was when I tried to push back a value to the end vector in classA. void classB::setFirstValue(double first) { this->getClassA().getVector().push_back(first); } This does absolutely nothing to the vector. It remains unchanged and I can't figure out why... Any ideas?

  Read the article

• Oracle Database 12c Spatial: Vector Performance Acceleration

  - by Okcan Yasin Saygili-Oracle

  Most business information has a location component, such as customer addresses, sales territories and physical assets. Businesses can take advantage of their geographic information by incorporating location analysis and intelligence into their information systems. This allows organizations to make better decisions, respond to customers more effectively, and reduce operational costs – increasing ROI and creating competitive advantage. Oracle Database, the industry’s most advanced database,  includes native location capabilities, fully integrated in the kernel, for fast, scalable, reliable and secure spatial and massive graph applications. It is a foundation for deploying enterprise-wide spatial information systems and locationenabled business applications. Developers can extend existing Oracle-based tools and applications, since they can easily incorporate location information directly in their applications, workflows, and services. Spatial Features The geospatial data features of Oracle Spatial and Graph option support complex geographic information systems (GIS) applications, enterprise applications and location services applications. Oracle Spatial and Graph option extends the spatial query and analysis features included in every edition of Oracle Database with the Oracle Locator feature, and provides a robust foundation for applications that require advanced spatial analysis and processing in the Oracle Database. It supports all major spatial data types and models, addressing challenging business-critical requirements from various industries, including transportation, utilities, energy, public sector, defense and commercial location intelligence. Network Data Model Graph Features The Network Data Model graph explicitly stores and maintains a persistent data model withnetwork connectivity and provides network analysis capability such as shortest path, nearest neighbors, within cost and reachability. It loads partitioned networks into memory on demand, overcomingthe limitations of in-memory analysis. Partitioning massive networks into manageable sub-networkssimplifies the network analysis. RDF Semantic Graph Features RDF Semantic Graph has native support for World Wide Web Consortium standards. It has open, scalable, and secure features for storing RDF/OWL ontologies anddata; native inference with OWL 2, SKOS and user-defined rules; and querying RDF/OWL data withSPARQL 1.1, Java APIs, and SPARQLgraph patterns in SQL. Video: Oracle Spatial and Graph Overview Oracle spatial is embeded on oracle database product. So ,we can use oracle installer (OUI).The Oracle Universal Installer (OUI) is used to install Oracle Database software. OUI is a graphical user interface utility that enables you to view the Oracle software that is installed on your machine, install new Oracle Database software, and delete Oracle software that you no longer need to use. Online Help is available to guide you through the installation process. One of the installation options is to create a database. If you select database creation, OUI automatically starts Oracle Database Configuration Assistant (DBCA) to guide you through the process of creating and configuring a database. If you do not create a database during installation, you must invoke DBCA after you have installed the software to create a database. You can also use DBCA to create additional databases. For installing Oracle Database 12c you may check the Installing Oracle Database Software and Creating a Database tutorial under the Oracle Database 12c 2-Day DBA Series.You can always check if spatial is available in your database using  "select comp_id, version, status, comp_name from dba_registry where comp_id='SDO';"   One of the most notable improvements with Oracle Spatial and Graph 12c can be seen in performance increases in vector data operations. Enabling the Spatial Vector Acceleration feature (available with the Spatial option) dramatically improves the performance of commonly used vector data operations, such as sdo_distance, sdo_aggr_union, and sdo_inside. With 12c, these operations also run more efficiently in parallel than in prior versions through the use of metadata caching. For organizations that have been facing processing limitations, these enhancements enable developers to make a small set of configuration changes and quickly realize significant performance improvements. Results include improved index performance, enhanced geometry engine performance, optimized secondary filter optimizations for Spatial operators, and improved CPU and memory utilization for many advanced vector functions. Vector performance acceleration is especially beneficial when using Oracle Exadata Database Machine and other large-scale systems. Oracle Spatial and Graph vector performance acceleration builds on general improvements available to all SDO_GEOMETRY operations in these areas: Caching of index metadata, Concurrent update mechanisms, and Optimized spatial predicate selectivity and cost functions. These optimizations enable more efficient use of: CPU, Memory, and Partitioning Resulting in substantial query performance improvements.UsageTo accelerate the performance of spatial operators, it is recommended that you set the SPATIAL_VECTOR_ACCELERATION database system parameter to the value TRUE. (This parameter is authorized for use only by licensed Oracle Spatial users, and its default value is FALSE.) You can set this parameter for the whole system or for a single session. To set the value for the whole system, do either of the following:Enter the following statement from a suitably privileged account:   ALTER SYSTEM SET SPATIAL_VECTOR_ACCELERATION = TRUE;Add the following to the database initialization file (xxxinit.ora):   SPATIAL_VECTOR_ACCELERATION = TRUE;To set the value for the current session, enter the following statement from a suitably privileged account:   ALTER SESSION SET SPATIAL_VECTOR_ACCELERATION = TRUE; Checkout the complete list of new features on Oracle.com @ http://www.oracle.com/technetwork/database/options/spatialandgraph/overview/index.html Spatial and Graph Data Sheet (PDF) Spatial and Graph White Paper (PDF)

  Read the article

• Why don't more games use vector art?

  - by Parris

  It would seem to me that vector art is more efficient in terms of resources/scalability; however, in most cases I have seen artists using bitmap/rasterized art. Is this a limitation put on the artists by the game programmers/designers? As a programmer I think vector art would be more ideal, since it allows for scaling up resolution without having to recreate the art, creating really large graphics or causing graphics to become blurry. The questions: why aren't more people using SVG/AI to create 2D game art? Would it actually be preferred (and who prefers it)? Are bitmap graphics a standard or a limitation (or maybe neither)? Background: I am working on an engine, and I had some kinda cool ideas for vector based graphics; however, I don't want to piss off artists in the future. I guess this is more a question centered around pragmatism and developing games.

  Read the article

• Vector Graphics in DirectX

  - by Doug

  I'm curious as to people's thoughts on the best way to use vector graphics in a directX game instead of rasterized textures(think Super Meat Boy). I want to remain resolution independent and don't want to downscale/upscale rasterized graphics. Also the idea would be for all assets to be vector graphics(again think Super Meat Boy). I've looked at Valve's paper "Improved Alpha-Tested Magnification for Vector Textures and Special Effects" and also looked at using shaders http://http.developer.nvidia.com/GPUGems3/gpugems3_ch25.html. Wondering if anyone has done something similar or an alternate approach. Cheers

  Read the article

• Collision detection - Smooth wall sliding, no bounce effect

  - by Joey

  I'm working on a basic collision detection system that provides point - OBB collision detection. I have around 200 cubes in my environment and I check (for now) each of them in turn and see if it collides. If it does I return the colliding face's normal, save the old player position and do some trigonometry to return a new player position for my wall sliding. edit I'll define my meaning of wall sliding: If a player walks in a vertical slope and has a slight horizontal rotation to the left or the right and keeps walking forward in the wall the player should slide a little to the right/left while continually walking towards the wall till he left the wall. Thus, sliding along the wall. Everything works fine and with multiple objects as well but I still have one problem I can't seem to figure out: smooth wall sliding. In my current implementation sliding along the walls make my player bounce like a mad man (especially noticable with gravity on and moving forward). I have a velocity/direction vector, a normal vector from the collided plane and an old and new player position. First I negate the normal vector and get my new velocity vector by substracting the inverted normal from my direction vector (which is the vector to slide along the wall) and I add this vector to my new Player position and recalculate the direction vector (in case I have multiple collisions). I know I am missing some step but I can't seem to figure it out. Here is my code for the collision detection (run every frame): Vector direction; Vector newPos(camera.GetOriginX(), camera.GetOriginY(), camera.GetOriginZ()); direction = newPos - oldPos; // Direction vector // Check for collision with new position for(int i = 0; i < NUM_OBJECTS; i++) { Vector normal = objects[i].CheckCollision(newPos.x, newPos.y, newPos.z, direction.x, direction.y, direction.z); if(normal != Vector::NullVector()) { // Get inverse normal (direction STRAIGHT INTO wall) Vector invNormal = normal.Negative(); Vector wallDir = direction - invNormal; // We know INTO wall, and DIRECTION to wall. Substract these and you got slide WALL direction newPos = oldPos + wallDir; direction = newPos - oldPos; } } Any help would be greatly appreciated! FIX I eventually got things up and running how they should thanks to Krazy, I'll post the updated code listing in case someone else comes upon this problem! for(int i = 0; i < NUM_OBJECTS; i++) { Vector normal = objects[i].CheckCollision(newPos.x, newPos.y, newPos.z, direction.x, direction.y, direction.z); if(normal != Vector::NullVector()) { Vector invNormal = normal.Negative(); invNormal = invNormal * (direction * normal).Length(); // Change normal to direction's length and normal's axis Vector wallDir = direction - invNormal; newPos = oldPos + wallDir; direction = newPos - oldPos; } }

  Read the article

• Finding the centeroid of a polygon?

  - by user146780

  I have tried: for each vertex, add to total, divide by number of verities to get center. I'v also tried: Find the topmost, bottommost - get midpoint... find leftmost, rightmost, find midpoint. Both of these did not return the perfect center because I'm relying on the center to scale a polygon. I want to scale my polygons so I may put a border around them. What is the best way to find the centroid of a polygon given that the polygon may be concave, convex and have many many sides of various lengths. Thanks

  Read the article

• How to delete duplicate vectors within a multidimensional vector?

  - by David

  I have a vector of vectors: vector< vector<int> > BigVec; It contains an arbitrary number of vectors, each of an arbitrary size. I want to delete not duplicate elements of each vector, but any vectors that are the exact same as another. I don't need to preserve the order of the vectors so I can sort etc.. It should be a really simple problem to solve but I'm new to this, my (not-working) best effort: for (int i = 0; i < BigVec.size(); i++) { for (int j = 1; j < BigVec.size() ; j++ ) { if (BigVec[i][0] == BigVec [j][i]); { BigVec.erase(BigVec.begin() + j); i = 0; // because i get the impression deleting a j = 1; // vector messes up a simple iteration through } } } I think there might be a solution using Unique(), but I can't get that to work either.

  Read the article

• Why would bitmap outperform vector, as3?

  - by VideoDnd

  Why would bitmap outperform vector? My Flash is for a large Kiosk, with rich media requirements and must function accurately as a counter. I want to keep everything vector for scalability. When I did a simple FPS test, I noticed my Bitmap version performed perfectly, and the all vector file was noticeably slower. PLEASE EXPLAIN • vector performance• what graphic standards I can apply• solutions for using vector KIOSK TEST ANIMATION RESULTS • only text and bitmap perform well, not vector • background and clouds OK, but more layers slow it down

  Read the article

• Ray Generation Inconsistency

  - by Myx

  I have written code that generates a ray from the "eye" of the camera to the viewing plane some distance away from the camera's eye: R3Ray ConstructRayThroughPixel(...) { R3Point p; double increments_x = (lr.X() - ul.X())/(double)width; double increments_y = (ul.Y() - lr.Y())/(double)height; p.SetX( ul.X() + ((double)i_pos+0.5)*increments_x ); p.SetY( lr.Y() + ((double)j_pos+0.5)*increments_y ); p.SetZ( lr.Z() ); R3Vector v = p-camera_pos; R3Ray new_ray(camera_pos,v); return new_ray; } ul is the upper left corner of the viewing plane and lr is the lower left corner of the viewing plane. They are defined as follows: R3Point org = scene->camera.eye + scene->camera.towards * radius; R3Vector dx = scene->camera.right * radius * tan(scene->camera.xfov); R3Vector dy = scene->camera.up * radius * tan(scene->camera.yfov); R3Point lr = org + dx - dy; R3Point ul = org - dx + dy; Here, org is the center of the viewing plane with radius being the distance between the viewing plane and the camera eye, dx and dy are the displacements in the x and y directions from the center of the viewing plane. The ConstructRayThroughPixel(...) function works perfectly for a camera whose eye is at (0,0,0). However, when the camera is at some different position, not all needed rays are produced for the image. Any suggestions what could be going wrong? Maybe something wrong with my equations? Thanks for the help.

  Read the article

• How to shrink-to-fit an std::vector in a memory-efficient way?

  - by dehmann

  I would like to 'shrink-to-fit' an std::vector, to reduce its capacity to its exact size, so that additional memory is freed. The standard trick seems to be the one described here: template< typename T, class Allocator > void shrink_capacity(std::vector<T,Allocator>& v) { std::vector<T,Allocator>(v.begin(),v.end()).swap(v); } The whole point of shrink-to-fit is to save memory, but doesn't this method first create a deep copy and then swaps the instances? So at some point -- when the copy is constructed -- the memory usage is doubled? If that is the case, is there a more memory-friendly method of shrink-to-fit? (In my case the vector is really big and I cannot afford to have both the original plus a copy of it in memory at any time.)

  Read the article

• Is there a version of the removeElement function in Go for the vector package like Java has in its V

  - by Brian T Hannan

  I am porting over some Java code into Google's Go language and I converting all code except I am stuck on just one part after an amazingly smooth port. My Go code looks like this and the section I am talking about is commented out: func main() { var puzzleHistory * vector.Vector; puzzleHistory = vector.New(0); var puzzle PegPuzzle; puzzle.InitPegPuzzle(3,2); puzzleHistory.Push(puzzle); var copyPuzzle PegPuzzle; var currentPuzzle PegPuzzle; currentPuzzle = puzzleHistory.At(0).(PegPuzzle); isDone := false; for !isDone { currentPuzzle = puzzleHistory.At(0).(PegPuzzle); currentPuzzle.findAllValidMoves(); for i := 0; i < currentPuzzle.validMoves.Len(); i++ { copyPuzzle.NewPegPuzzle(currentPuzzle.holes, currentPuzzle.movesAlreadyDone); copyPuzzle.doMove(currentPuzzle.validMoves.At(i).(Move)); // There is no function in Go's Vector that will remove an element like Java's Vector //puzzleHistory.removeElement(currentPuzzle); copyPuzzle.findAllValidMoves(); if copyPuzzle.validMoves.Len() != 0 { puzzleHistory.Push(copyPuzzle); } if copyPuzzle.isSolutionPuzzle() { fmt.Printf("Puzzle Solved"); copyPuzzle.show(); isDone = true; } } } } If there is no version available, which I believe there isn't ... does anyone know how I would go about implementing such a thing on my own?

  Read the article

• Finding the centroid of a polygon?

  - by user146780

  I have tried: for each vertex, add to total, divide by number of verities to get center. I'v also tried: Find the topmost, bottommost - get midpoint... find leftmost, rightmost, find midpoint. Both of these did not return the perfect center because I'm relying on the center to scale a polygon. I want to scale my polygons so I may put a border around them. What is the best way to find the centroid of a polygon given that the polygon may be concave, convex and have many many sides of various lengths. Thanks

  Read the article

• Is the old vector get cleared? If yes, how and when?

  - by user180866

  I have the following code: void foo() { vector<double> v(100,1); // line 1 // some code v = vector<double>(200,2); // line 2 // some code } what happened to the vector of size 100 after the second line? Is it gets cleared by itself? If the answer is yes, how and when it is cleared? By the way, is there any other "easy and clean" ways to change the vector as in line 2? I don't want things like v.resize(200); for (int i=0; i<200; i++) v[i] = 2;

  Read the article

• C++ vector<T>::iterator operator +

  - by Tom

  Hi, Im holding an iterator that points to an element of a vector, and I would like to compare it to the next element of the vector. Here is what I have Class Point{ public: float x,y; } //Somewhere in my code I do this vector<Point> points = line.getPoints(); foo (points.begin(),points.end()); where foo is: void foo (Vector<Point>::iterator begin,Vector<Point>::iterator end) { std::Vector<Point>::iterator current = begin; for(;current!=end-1;++current) { std::Vector<Point>::iterator next = current + 1; //Compare between current and next. } } I thought that this would work, but current + 1 is not giving me the next element of the vector. I though operator+ was the way to go, but doesnt seem so. Is there a workaround on this? THanks

  Read the article

• fastest engine to convert PDF into PNG

  - by skyde

  I would like to know which of the opensource PDF engine can convert a pdf into a image the fastest. I don't care about the quality of the result (antialiasing ...) For my project it need to be very very fast. I would probably need to build my own but i dont wan't to start from scratch.

  Read the article

• How to restrict the range of elements of C++ STL vector?

  - by cambr

  vector<int> l; for(int i=0;i<10;i++){ l.push_back(i); } I want the vector to only be able to store numbers from a specified range (or set). How can that be done, in general? In particular, I want to restrict the vector to beonly be able to store single digits. So, if I do a l[9]++, it should give me an error or warn me. (because 10 is not a single digit number). Similarly, l[0]-- should warn me. Is there a way to do this using C++ STL vector?

  Read the article

• Attribute vector emptying itself

  - by ravloony

  Hello, I have two classes, derived from a common class. The common class has a pure virtual function called execute(), which is implemented in both derived classes. In the inherited class I have an attribute which is a vector. In both execute() methods I overwrite this vector with a result. I access both classes from a vector of pointers to their objects. The problem is when I try to access the result vector form outside the objects. In one case I can get the elements (which are simply pointers), in the other I cannot, the vector is empty. Code: class E; class A{ protected: vector<E*> _result; public: virtual void execute()=0; vector<E*> get_result(); }; vector<E*> A::get_result() { return _result; } class B : public A { public: virtual void execute(); }; B::execute() { //... _result = tempVec; return; } class C : public A { public: virtual void execute(); }; C::execute() { //different stuff to B _result = tempvec; return; } main() { B* b = new B(); C* c = new C(); b->execute(); c->execute(); b->get_result();//returns full vector c->get_result(); //returns empty vector!! } I have no idea what is going on here... I have tried filling _result by hand from a temp vector in the offending class, doing the same with vector::assign(), nothing works. And the other object works perfectly. I must be missing something.... Any help would be greatly appreciated.

  Read the article

• which is better in general, map or vector in c++?

  - by tsubasa

  As I know that accessing an element in vector takes constant time while in map takes logarithmic time. However, storing a map takes less memory than storing a vector. Therefore, I want to ask which one is better in general? I'm considering using one of those two in my program, which has about 1000 elements. I plan to use 3 dimensional vector, which would take 1000x1000x1000 elements.

  Read the article

< Previous Page | 7 8 9 10 11 12 13 14 15 16 17 18  | Next Page >