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  • Mat matrix multiplication, openCV?

    - by facebook-1593205594
    I initialized two Mat images as: Mat ft=Mat::zeros(src.rows,src.cols,CV_32FC1),h=Mat::zeros(src.rows,src.cols,CV_32FC1); and then i have some calculations: ft has fourier transform stored for an image, and h has matrix for Laplacian filtering in fourier domain.......they both have same dimensions, and then i did multiplication of them using both h*ft and gemm(h,ft,1,NULL,0,temp); function call but while executing it shows some problems..... it reads like this: opencv error assertion failed (some long code and at last says something about gemm in ....matmul.cpp)......termination called after throwing exception of 'cv::exception'

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  • How to stringfy a swig matrix object in python

    - by leo
    Hi, I am using swig wrapper of openbabel(written in C++, and supply a python wrapper through swig) Below i just use it to read a molecule structure file and get the unitcell property of it. import pybel for molecule in pybel.readfile('pdb','./test.pdb'): unitcell = molecule.unitcell print unitcell |.. |.. The unitcell has function CellMatrix(), unitcell.GetCellMatrix() <22 the OpenBabel::matrix3x3 is something like : 1 2 3 4 5 6 7 8 9 i am wondering how to print out the contents of the matrix3*3 . I have tried str and repr with it. Any general way to stringfy the contents of a matrix wrapped by swing in python ? thanks

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  • System.AccessViolationException when using TPT inheritance in Entity Framework CTP5

    - by Ben
    Hi, I'm using TPT inheritance in EF CTP5 with SQL CE 4. I have an abstract base class "Widget" with common properties like "Title". I can successfully save concrete Widget implementations e.g. "TwitterWidget". However, I have a problem retrieving all widgets (or rather ALL widget implementations). My repository exposes the following: public IQueryable<Widget> GetAll(); This effectively returns the IDbSet from the DbContext. The following queries work fine: repo.GetAll().ToList(); repo.GetAll().Where(w => w.Title == "Test").ToList(); repo.GetAll().SingleOrDefault(w => w.Title == "Test"); repo.GetAll().Where(w => w.Title == "Test").OrderBy(x => x.Title).ToList(); However, if I write the following query: repo.GetAll().OrderBy(w => w.Title); I get the following error: Test 'PlanetCloud.Portfolio.Tests.Data.PersistenceTestFixture.Can_get_widgets' failed: System.AccessViolationException : Attempted to read or write protected memory. This is often an indication that other memory is corrupt. at System.Data.SqlServerCe.NativeMethodsHelper.GetValues(IntPtr pSeCursor, Int32 seGetColumn, IntPtr prgBinding, Int32 cDbBinding, IntPtr pData, IntPtr pError) at System.Data.SqlServerCe.NativeMethods.GetValues(IntPtr pSeCursor, Int32 seGetColumn, IntPtr prgBinding, Int32 cDbBinding, IntPtr pData, IntPtr pError) at System.Data.SqlServerCe.SqlCeDataReader.FetchValue(Int32 index) at System.Data.SqlServerCe.SqlCeDataReader.IsDBNull(Int32 ordinal) at lambda_method(Closure , Shaper ) at System.Data.Common.Internal.Materialization.Shaper.HandleEntityAppendOnly[TEntity](Func`2 constructEntityDelegate, EntityKey entityKey, EntitySet entitySet) at lambda_method(Closure , Shaper ) at System.Data.Common.Internal.Materialization.Coordinator`1.ReadNextElement(Shaper shaper) at System.Data.Common.Internal.Materialization.Shaper`1.SimpleEnumerator.MoveNext() at System.Collections.Generic.List`1..ctor(IEnumerable`1 collection) at System.Linq.Enumerable.ToList[TSource](IEnumerable`1 source) However, I can execute the following query without problems: var widgets = repo.GetAll().OfType<Widget>().OrderBy(w => w.Title).ToList(); So if I specify the type as the base class prior to my orderby clause it works. The question is why?

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  • How to find vector for the quaternion from X Y Z rotations

    - by can poyrazoglu
    I am creating a very simple project on OpenGL and I'm stuck with rotations. I am trying to rotate an object indepentdently in all 3 axes: X, Y, and Z. I've had sleepless nights due to the "gimbal lock" problem after rotating about one axis. I've then learned that quaternions would solve my problem. I've researched about quaternions and implementd it, but I havent't been able to convert my rotations to quaternions. For example, if I want to rotate around Z axis 90 degrees, I just create the {0,0,1} vector for my quaternion and rotate it around that axis 90 degrees using the code here: http://iphonedevelopment.blogspot.com/2009/06/opengl-es-from-ground-up-part-7_04.html (the most complicated matrix towards the bottom) That's ok for one vector, but, say, I first want to rotate 90 degrees around Z, then 90 degrees around X (just as an example). What vector do I need to pass in? How do I calculate that vector. I am not good with matrices and trigonometry (I know the basics and the general rules, but I'm just not a whiz) but I need to get this done. There are LOTS of tutorials about quaternions, but I seem to understand none (or they don't answer my question). I just need to learn to construct the vector for rotations around more than one axis combined. UPDATE: I've found this nice page about quaternions and decided to implement them this way: http://www.cprogramming.com/tutorial/3d/quaternions.html Here is my code for quaternion multiplication: void cube::quatmul(float* q1, float* q2, float* resultRef){ float w = q1[0]*q2[0] - q1[1]*q2[1] - q1[2]*q2[2] - q1[3]*q2[3]; float x = q1[0]*q2[1] + q1[1]*q2[0] + q1[2]*q2[3] - q1[3]*q2[2]; float y = q1[0]*q2[2] - q1[1]*q2[3] + q1[2]*q2[0] + q1[3]*q2[1]; float z = q1[0]*q2[3] + q1[1]*q2[2] - q1[2]*q2[1] + q1[3]*q2[0]; resultRef[0] = w; resultRef[1] = x; resultRef[2] = y; resultRef[3] = z; } Here is my code for applying a quaternion to my modelview matrix (I have a tmodelview variable that is my target modelview matrix): void cube::applyquat(){ float& x = quaternion[1]; float& y = quaternion[2]; float& z = quaternion[3]; float& w = quaternion[0]; float magnitude = sqrtf(w * w + x * x + y * y + z * z); if(magnitude == 0){ x = 1; w = y = z = 0; }else if(magnitude != 1){ x /= magnitude; y /= magnitude; z /= magnitude; w /= magnitude; } tmodelview[0] = 1 - (2 * y * y) - (2 * z * z); tmodelview[1] = 2 * x * y + 2 * w * z; tmodelview[2] = 2 * x * z - 2 * w * y; tmodelview[3] = 0; tmodelview[4] = 2 * x * y - 2 * w * z; tmodelview[5] = 1 - (2 * x * x) - (2 * z * z); tmodelview[6] = 2 * y * z - 2 * w * x; tmodelview[7] = 0; tmodelview[8] = 2 * x * z + 2 * w * y; tmodelview[9] = 2 * y * z + 2 * w * x; tmodelview[10] = 1 - (2 * x * x) - (2 * y * y); tmodelview[11] = 0; glMatrixMode(GL_MODELVIEW); glPushMatrix(); glLoadMatrixf(tmodelview); glMultMatrixf(modelview); glGetFloatv(GL_MODELVIEW_MATRIX, tmodelview); glPopMatrix(); } And my code for rotation (that I call externally), where quaternion is a class variable of the cube: void cube::rotatex(int angle){ float quat[4]; float ang = angle * PI / 180.0; quat[0] = cosf(ang / 2); quat[1] = sinf(ang/2); quat[2] = 0; quat[3] = 0; quatmul(quat, quaternion, quaternion); applyquat(); } void cube::rotatey(int angle){ float quat[4]; float ang = angle * PI / 180.0; quat[0] = cosf(ang / 2); quat[1] = 0; quat[2] = sinf(ang/2); quat[3] = 0; quatmul(quat, quaternion, quaternion); applyquat(); } void cube::rotatez(int angle){ float quat[4]; float ang = angle * PI / 180.0; quat[0] = cosf(ang / 2); quat[1] = 0; quat[2] = 0; quat[3] = sinf(ang/2); quatmul(quat, quaternion, quaternion); applyquat(); } I call, say rotatex, for 10-11 times for rotating only 1 degree, but my cube gets rotated almost 90 degrees after 10-11 times of 1 degree, which doesn't make sense. Also, after calling rotation functions in different axes, My cube gets skewed, gets 2 dimensional, and disappears (a column in modelview matrix becomes all zeros) irreversibly, which obviously shouldn't be happening with a correct implementation of the quaternions.

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  • System.Windows.Forms.DataVisualization Namespace Fine in One Class but Not in Another

    - by jxpx777
    Hi. I'm getting this error The type or namespace name 'DataVisualization' does not exist in the namespace 'System.Windows.Forms' (are you missing an assembly reference?) Here is my using section of the class: using System; using System.Collections; using System.Collections.Generic; using System.Windows.Forms.DataVisualization.Charting; using System.Windows.Forms.DataVisualization.Charting.Borders3D; using System.Windows.Forms.DataVisualization.Charting.ChartTypes; using System.Windows.Forms.DataVisualization.Charting.Data; using System.Windows.Forms.DataVisualization.Charting.Formulas; using System.Windows.Forms.DataVisualization.Charting.Utilities; namespace myNamespace { public class myClass { // Usual class stuff } } The thing is that I am using the same DataVisualization includes in another class. The only thing that I can think that is different is that the classes that are giving this missing namespace error are Solution Items rather than specific to a project. The projects reference them by link. Anyone have thoughts on what the problem is? I've installed the chart component, .Net 3.5 SP1, and the Chart Add-in for Visual Studio 2008. UPDATE: I moved the items from Solution Items to be regular members of my project and I'm still seeing the same behavior. UPDATE 2: Removing the items from the Solution Items and placing them under my project worked. Another project was still referencing the files which is why I didn't think it worked previously. I'm still curious, though, why I couldn't use the namespace when the classes were Solution Items but moving them underneath a project (with no modifications, mind you) instantly made them recognizable. :\

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  • ASP.Net MVC 2 Error Method not found: 'System .string

    - by Saravanan I M
    I converted my website from asp.net mvc 1.0 to 2.0. After converting that i am getting the following error in actionlink Method not found: 'System.String System.Web.Mvc.Html.LinkExtensions.RouteLink(System.Web.Mvc.HtmlHelper, System.String, System.Web.Routing.RouteValueDictionary, System.Collections.Generic.IDictionary`2<System.String,System.Object>)'. Line 102: <%var Signin = Html.Resource("globalResources, Signin"); %> Line 103: <% if (string.IsNullOrEmpty(Signin)) Signin = "Signin"; %> Line 104: <%= Html.ActionLink<AccountController>(cntrl => cntrl.LogOn(), Signin.ToString(), new { @class = "defaultmaster" })%> Line 105: | Line 106: <%var register = Html.Resource("globalResources, Register"); %> Source File: e:\Muchsocial\Sourcecode\Muchsocial\Views\Shared\Muchsocial.Master Line: 104

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  • Matrix Comparison algorithm

    - by SysAdmin
    If you have 2 Matrices of dimensions N*M. what is the best way to get the difference Rect? Example: 2 3 2 3 2 3 2 3 2 3 2 3 2 3 2 3 2 3 2 3 2 3 2 3 2 3 2 3 2 3 2 3 2 3 4 5 4 3 2 3 <---> 2 3 2 3 2 3 2 3 2 3 4 5 2 3 2 3 2 3 2 3 2 3 2 3 2 3 2 3 2 3 2 3 2 3 2 3 2 3 2 3 | | \ / Rect([2,2] , [3,4]) 4 5 4 4 5 2-> A (2 x 3 Matrix) The best I could think of is to scan from Top-Left hit the point where there is difference. Then scan from Bottom Right and hit the point where there is a difference. But In worst case, this is O(N*M). is there a better efficient algorithm?

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  • How to register System.DirectoryServices for use in SQL CLR User Functions?

    - by Saul Dolgin
    I am porting an old 32-bit COM component that was written in VB6 for the purpose of reading and writing to an Active Directory server. The new solution will be in C# and will use SQL CLR user functions. The assembly that I am trying to deploy to SQL Server contains a reference to System.DirectoryServices. The project does compile without any errors but I am unable to deploy the assembly to the SQL Server because of the following error: Error: Assembly 'system.directoryservices, version=2.0.0.0, culture=neutral, publickeytoken=b03f5f7f11d50a3a.' was not found in the SQL catalog. What are the correct steps for registering System.DirectoryServices on SQL Server?

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  • How can I store Perl's system function output to a variable?

    - by karthi-27
    I have a problem with the system function. I want to store the system functions output to a variable. For example, system("ls"); Here I want all the file names in the current directory to store in a variable. I know that I can do this by redirecting the output into a file and read from that and store that to a variable. But I want a efficient way than that. Is there any way .

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  • Reportviewer - Print report - matrix report expanding horizontally to multiple pages, avoid repeating row header

    - by abc0077
    I am generating a matrix report dynamically using report viewer version 9.0 in visual studio 2010. If i export save and print then it works normally. If there more columns report expands horizontally across mutiple pages. If i give Print option available in the toolbar of the report viewer. The columns are moved to second page which is correct but the row headers (product 1, product 2) should not be repeated in the second page.In the second page report should have all details except the product information. I am also interested to know whether it is the functionality of this version report viewer.

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  • Finding matching submatrics inside a matrix

    - by DaveO
    I have a 100x200 2D array expressed as a numpy array consisting of black (0) and white (255) cells. It is a bitmap file. I then have 2D shapes (it's easiest to think of them as letters) that are also 2D black and white cells. I know I can naively iterate through the matrix but this is going to be a 'hot' portion of my code so speed is an concern. Is there a fast way to perform this in numpy/scipy? I looked briefly at Scipy's correlate function. I am not interested in 'fuzzy matches', only exact matches. I also looked at some academic papers but they are above my head.

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  • Last Observation Carried Forward In a data frame?

    - by Tal Galili
    Hi all, I wish to implement a "Last Observation Carried Forward" for a data set I am working on which has missing values at the end of it. Here is a simple code to do it (question after it): LOCF <- function(x) { # Last Observation Carried Forward (for a left to right series) LOCF <- max(which(!is.na(x))) # the location of the Last Observation to Carry Forward x[LOCF:length(x)] <- x[LOCF] return(x) } # example: LOCF(c(1,2,3,4,NA,NA)) LOCF(c(1,NA,3,4,NA,NA)) Now this works great for simple vectors. But if I where to try and use it on a data frame: a <- data.frame(rep("a",4), 1:4,1:4, c(1,NA,NA,NA)) a t(apply(a, 1, LOCF)) # will make a mess It will turn my data frame into a character matrix. Can you think of a way to do LOCF on a data.frame, without turning it into a matrix? (I could use loops and such to correct the mess, but would love for a more elegant solution) Cheers, Tal

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  • How to access a matrix in a matlab struct's field from a mex function?

    - by B. Ruschill
    I'm trying to figure out how to access a matrix that is stored in a field in a matlab structure from a mex function. That's awfully long winded... Let me explain: I have a matlab struct that was defined like the following: matrixStruct = struct('matrix', {4, 4, 4; 5, 5, 5; 6, 6 ,6}) I have a mex function in which I would like to be able to receive a pointer to the first element in the matrix (matrix[0][0], in c terms), but I've been unable to figure out how to do that. I have tried the following: /* Pointer to the first element in the matrix (supposedly)... */ double *ptr = mxGetPr(mxGetField(prhs[0], 0, "matrix"); /* Incrementing the pointer to access all values in the matrix */ for(i = 0; i < 3; i++){ printf("%f\n", *(ptr + (i * 3))); printf("%f\n", *(ptr + 1 + (i * 3))); printf("%f\n", *(ptr + 2 + (i * 3))); } What this ends up printing is the following: 4.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 I have also tried variations of the following, thinking that perhaps it was something wonky with nested function calls, but to no avail: /* Pointer to the first location of the mxArray */ mxArray *fieldValuePtr = mxGetField(prhs[0], 0, "matrix"); /* Get the double pointer to the first location in the matrix */ double *ptr = mxGetPr(fieldValuePtr); /* Same for loop code here as written above */ Does anyone have an idea as to how I can achieve what I'm trying to, or what I am potentially doing wrong? Thanks! Edit: As per yuk's comment, I tried doing similar operations on a struct that has a field called array which is a one-dimensional array of doubles. The struct containing the array is defined as follows: arrayStruct = struct('array', {4.44, 5.55, 6.66}) I tried the following on the arrayStruct from within the mex function: mptr = mxGetPr(mxGetField(prhs[0], 0, "array")); printf("%f\n", *(mptr)); printf("%f\n", *(mptr + 1)); printf("%f\n", *(mptr + 2)); ...but the output followed what was printed earlier: 4.440000 0.000000 0.000000

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  • What free expert system can You recommend (with higher functionality then CLIPS)?

    - by Martin
    Hi, I'm trying to find best free expert system, with the highest functionality. I know about CLIPS, but is there another system, for example being able to accept percent of confidence for each rule (fuzzy logic). I need it to know will I be able to do fast a short project using expert system, with highest functionality. But anyways, it's interesting is there an open source program that aims to gather different AI methods (whitch there are plenty of), and use them together. So I would be extremely thankeful for any info about more robust CLIPS, or similar programs. Thanks!

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  • How can I run Perl system commands in the background?

    - by sid_com
    #!/usr/bin/env perl use warnings; use strict; use 5.012; use IPC::System::Simple qw(system); system( 'xterm', '-geometry', '80x25-5-5', '-bg', 'green', '&' ); say "Hello"; say "World"; I tried this to run the xterm-command in the background, but it doesn't work: No absolute path found for shell: & What would be the right way to make it work?

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  • Multiplying Block Matrices in Numpy

    - by Ada Xu
    Hi Everyone I am python newbie I have to implement lasso L1 regression for a class assignment. This involves solving a quadratic equation involving block matrices. minimize x^t * H * x + f^t * x where x 0 Where H is a 2 X 2 block matrix with each element being a k dimensional matrix and x and f being a 2 X 1 vectors each element being a k dimension vector. I was thinking of using nd arrays. such that np.shape(H) = (2, 2, k, k) np.shape(x) = (2, k) But I figured out that np.dot(X, H) doesn't work here. Is there an easy way to solve this problem? Thanks in advance.

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  • JAVA. Writing a matrix in a file using column information.

    - by Dmitry
    Hello, everybody! I have a file in which a matrix is stored. This file has a RandomAccessFile type. This matrix is stored by columns. I mean that in an i-th row of this matrix an i-th column (of a real matrix) is stored. There is an example: i-th row: 1 2 3 4 (in the file). That means that the real matrix has an i-th column: (1 2 3 4)(transpose). I need to save this matrix in natural way (by rows) in a new file, which I will then open with FileReader and display with TestArea. DO you know, how to do that? If so, please help =)

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  • Reading Matrices in MATLAB and assigning coordinates to the entries

    - by Michael Schofield
    Hi, I'm a bit new to MATLAB. Basically, I have a 25x25 Matrix, complete with various random entries ranging from 0 to 3. I need to write a program that reads this matrix, and assigns x-y coordinates to the entries, so that when I ask for an input of a particular x-y coordinate which has, say an entry of 3, then it will result in an error. I'm a bit overwhelmed - but I understand the general concept of what I'm supposed to be finding. I'm wondering if I should use a plot instead to help me.

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  • Generate matrix with value flags

    - by pagid
    I do have a solution for the following problem but it's quite ugly and it can most likely be done in a much shorter way. Would be great to get your help. My input looks like this: C1 C2 A B B D D C A D and my output should look like this: A B C D 1 1 0 0 0 1 0 1 0 0 1 1 1 0 0 1 My current solution is: index <- unique(unlist(input[,1:2])) output <- matrix(0,nrows=dim(input),ncols=length(index)) for(i in 1:dim(input)) { output[i, input[i,]$C1] <- 1 output[i, input[i,]$C2] <- 1 } Of course 4-5 lines is actually fine - but even as an R beginner this doesn't feel right to use a for loop. Besides that my actual data has much more than two columns, therefore this doesn't look nice in the end. How would I do that in a smarter way? Cheers

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  • Help me to explain the F# Matrix transpose function

    - by Kev
    There is a Matrix transpose function: let rec transpose = function | (_::_)::_ as M -> List.map List.head M :: transpose (List.map List.tail M) | _ -> [] [[1; 2; 3]; [4; 5; 6]; [7; 8; 9]] |> transpose |> printfn "%A" It works fine. What does ( _ :: _ ) :: _ mean? I don't understand the whole code! Who can explain it? Thank You!

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  • How to store matrix information in MySQL?

    - by dedalo
    Hi, I'm working on an application that analizes music similarity. In order to do that I proccess audio data and store the results in txt files. For each audio file I create 2 files, 1 containing and 16 values (each value can be like this:2.7000023942731723) and the other file contains 16 rows, each row containing 16 values like the one previously shown. I'd like to store the contents of these 2 file in a table of my MySQL database. My table looks like: Name varchar(100) Author varchar (100) in order to add the content of those 2 file I think I need to use the BLOB data type: file1 blob file2 blob My question is how should I store this info in the data base? I'm working with Java where I have a double array containing the 16 values (for the file1) and a matrix containing the file2 info. Should I process the values as strings and add them to the columns in my database? Thanks

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  • passing a float as a pointer to a matrix

    - by numerical25
    Honestly, I couldnt think of a better title for this issue because I am having 2 problems and I don't know the cause. The first problem I have is this //global declaration float g_posX = 0.0f; ............. //if keydown happens g_posX += 0.03f; &m_mtxView._41 = g_posX; I get this error cannot convert from 'float' to 'float *' So I assume that the matrix only accepts pointers. So i change the varible to this.... //global declaration float *g_posX = 0.0f; ............. //if keydown happens g_posX += 0.03f; &m_mtxView._41 = &g_posX; and I get this error cannot convert from 'float' to 'float *' which is pretty much saying that I can not declare g_posX as a pointer. honestly, I don't know what to do.

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  • How to calculate the state of a graph?

    - by zcb
    Given a graph G=(V,E), each node i is associated with 'Ci' number of objects. At each step, for every node i, the Ci objects will be taken away by the neighbors of i equally. After K steps, output the number of objects of the top five nodes which has the most objects. Some Constrains: |V|<10^5, |E|<2*10^5, K<10^7, Ci<1000 My current idea is: represent the transformation in each step with a matrix. This problem is converted to the calculation of the power of matrix. But this solution is much too slow considering |V| can be 10^5. Is there any faster way to do it?

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  • I want to make a wrapped acces type for certain internals of one of classes and I have some performa

    - by Alex
    I am writing an abstract matrix class (and some concrete subclasses) for use on very differing hardwares/architectures, etc. and I want to write a row and column type that provides a transparent reference to the rows and columns of the matrix. However, I want to tune for performance, so I'd like this class to be essentially a compiler construct. In other words, I'm willing to sacrifice some dev time to making the overhead of these classes as small as possible. I assume all (small) methods would want to be virtual? Keep the structure small? Any other suggestions?

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  • How to split up input from System.in

    - by zzaw
    Alright so I'm working on something where I take input from System.in; the first line is an int (n) representing the size of a matrix. The next n lines are the matrix itself like so: 10 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 1 0 1 0 0 0 0 0 0 0 0 1 0 0 1 1 0 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 1 1 0 0 0 1 1 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 The problem is there may be multiple matrix's in a single input, so the next line would have another int and the corresponding matrix underneath until it hits a line with a single 0. I then have to pass each matrix along with the size at the top as a BufferedReader to a method which adds the numbers to a 2D array. I'm just a little unsure on how to split the input up and send it to the method. Would making a new BufferedReader using skip() and specifying a size each time work? The biggest problem I seem to be running into is reading the size but then the size being excluded as it has already been read. Cheers

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