javaopencljocl

How to read txt file in OpenCL


I'm new to OpenCL. Does anybody know how to read a text file through OpenCL? Because I want to be able to read the file and split the content into some arrays. For the example, I have txt file consists: 1010101 1 1010111. I want to get 1010101 as array a and 1010111 as array b. Here, we see a tab/space, it has tab delimiter with "1", so I need to split with delimiter "\t1" as well.

Here my the main code:

for (int i = 0; i < N; i++) { 

            System.out.println("perturb node: "+i);
            cs=calcDistanceCs();//ok
            System.out.println("csTemp: "+Arrays.toString(cs));
            //System.out.println("csTemp: "+cs); 
            for (int j = 0; j < N; j++) {

                if (j!=i) {
                    System.out.println("target node: "+j);
                    nTarget=j;
                    rs=calcDistanceRs();

                    System.out.println("rsTemp: "+Arrays.toString(rs));

                    //System.out.println("rsTemp: "+rs);

                    eff=dtmp/numofRStates;
                    System.out.println("Effectiveness "+eff);

                    //print-out result
                    pw.println(i+"\t"+eff+"\t"+j);
                    // flush the writer
                    pw.flush();
                } 
            }
        }
        Pointer srcA = Pointer.to(cs);
        Pointer srcB = Pointer.to(rs);
        //Pointer dst = Pointer.to(resultArr);

        // The platform, device type and device number
        final int platformIndex = 0;
        final long deviceType = CL_DEVICE_TYPE_ALL;
        final int deviceIndex = 0;

        // Enable exceptions and subsequently omit error checks in this sample
        CL.setExceptionsEnabled(true);

        // Obtain the number of platforms
        int numPlatformsArray[] = new int[1];
        clGetPlatformIDs(0, null, numPlatformsArray);
        int numPlatforms = numPlatformsArray[0];

        //obtain a platform id
        System.out.println("Obtaining platform..."); //running, muncul
        cl_platform_id platforms[] = new cl_platform_id[numPlatforms];
        clGetPlatformIDs(platforms.length, platforms, null);
        cl_platform_id platform = platforms[platformIndex];
        System.out.println("Platform id: "+platform); //uda langsung ke string tanpa harus diconvert

        //Initialize the context properties
        cl_context_properties contextProperties = new cl_context_properties();
        contextProperties.addProperty(CL_CONTEXT_PLATFORM, platform);        

        // Obtain the number of devices for the platform
        int numDevicesArray[] = new int[1];
        clGetDeviceIDs(platform, deviceType, 0, null, numDevicesArray);
        int numDevices = numDevicesArray[0];

        // Obtain a device ID 
        cl_device_id devices[] = new cl_device_id[numDevices];
        clGetDeviceIDs(platform, deviceType, numDevices, devices, null);
        cl_device_id device = devices[deviceIndex];

        // Create a context for the selected device
        cl_context context = clCreateContext(contextProperties, 1, new cl_device_id[]{device},null, null, null);  
        //create an opencl context on a gpu device
        //cl_context context=clCreateContextFromType(contextProperties,CL_DEVICE_TYPE_GPU,null,null,null);
        if (context==null) {
            /*if no context for a gpu device could be created,
            try to create one for a cpu device
            */
            System.out.println("Cannot create GPU context...");
            context=clCreateContextFromType(contextProperties, CL_DEVICE_TYPE_CPU, null, null, null);
            if (context==null) {
                System.out.println("Unable to create a context");
                return;
            }else{
                System.out.println("Successfully created CPU context ^^");
            }
        }else{
            System.out.println("Successfully created GPU context...");
        }

        // Create a command-queue for the selected device
        cl_command_queue commandQueue = clCreateCommandQueue(context, device, 0, null);

        // Allocate the memory objects for the input- and output data
        cl_mem memObjects[] = new cl_mem[2];
        memObjects[0] = clCreateBuffer(context, 
                CL_MEM_READ_ONLY | CL_MEM_COPY_HOST_PTR,
                Sizeof.cl_char * N, srcA, null);
        memObjects[1] = clCreateBuffer(context, 
                CL_MEM_READ_ONLY | CL_MEM_COPY_HOST_PTR,
                Sizeof.cl_char * N, srcB, null);
        /*            memObjects[2] = clCreateBuffer(context,
        CL_MEM_READ_WRITE,
        Sizeof.cl_float * N, null, null);*/

        // Create the program from the source code

        System.out.println("Reading file from kernels...");
        String programSource=readFile("kernel_/CalEff.cl"); //membaca file dari luar folder src--sukses ^^

        //create the program from the source code 
        cl_program program=clCreateProgramWithSource(context,1,new String[]{programSource},null,null);        

        // Build the program
        clBuildProgram(program, 0, null, null, null, null);

        // Create the kernel
        cl_kernel kernel = clCreateKernel(program, "Effectiveness", null); //nama procedure yg dipanggil di kernel/opencl

        // Set the arguments for the kernel -->kernel, arg index,long arg size, pointer
        clSetKernelArg(kernel, 0, Sizeof.cl_mem, Pointer.to(memObjects[0]));//jumlahnya ada 3 cz yg dideklarasi jg ada3
        clSetKernelArg(kernel, 1, Sizeof.cl_mem, Pointer.to(memObjects[1]));
        clSetKernelArg(kernel, 2, Sizeof.cl_mem, Pointer.to(memObjects[2]));

        // Set the work-item dimensions
        long global_work_size[] = new long[]{N};
        long local_work_size[] = new long[]{1};//This means each item is a separate workgroup

        // Execute the kernel
        clEnqueueNDRangeKernel(commandQueue, kernel, 1, null,global_work_size, local_work_size, 0, null, null); //execure each array in parallel

        // Read the output data-->from c parameter /kalo dibutuhkan
        //clEnqueueReadBuffer(commandQueue, memObjects[2], CL_TRUE, 0,N * Sizeof.cl_float, dst, 0, null, null);
        /*BASIC END HERE*/

        // Release kernel, program, and memory objects
        clReleaseMemObject(memObjects[0]);
        clReleaseMemObject(memObjects[1]);
        clReleaseMemObject(memObjects[2]);
        clReleaseKernel(kernel);
        clReleaseProgram(program);
        clReleaseCommandQueue(commandQueue);
        clReleaseContext(context);

But for calcDistanceCs() and calcDistanceRs() they both need to read a txt file. Then from that file i got the array (stateArray[]) like this:

    FileReader fr;
    LineNumberReader lnr; 
    String str;
    int i;
    System.out.println("Calculate distance Current State: ");
    try{
        // create new reader
        fr = new FileReader("AttractorCs.txt");
        lnr = new LineNumberReader(fr);

        csLine=0;
        // read lines till the end of the stream
        while((str=lnr.readLine())!=null){
            i=lnr.getLineNumber();

            csBariske=i;
            csBaris=str;

            if(csBaris!=null){
                List<ModEff> listState= new LinkedList<>();
                String[] stateArray;            
                stateArray=csBaris.split("\t");

                node1=BinaryStringtoBinaryByteArrAwal(stateArray[0]);
                node2=BinaryStringtoBinaryByteArrAkhir(stateArray[2]);

            }
            if (csBariske % 2 == 1) {
                it_attcGanj=String.valueOf(node1)+String.valueOf(node2);  
            }else{
                it_attcGen=String.valueOf(node2)+String.valueOf(node1);

                it_att=it_attcGanj+it_attcGen;
                nodeCsArr = convertNodeArrToByteArr(it_att); 
            }
            csLine++;
        }

        lnr.close();
    }catch(Exception e){

       // if any error occurs
       e.printStackTrace();
    }
    System.gc();
    return nodeCsArr;

Here the example text file that I need to read: 00010000000000000000000000001000000000000000000000110000000001000000000010010111000000000000000000100000000000000001001000000000000000000000000000000001000000000000000000000000100000100000000000001000000000000001010000000000010000000000000000001000000000000001000000001000001100101000000000000010000000000010000000000000000000000000010000000000000110000000000001000000000000000000000100000000001001001110010000000000000000100000000000000000001000000000010000000010000000010000000000000000000010000000000100110000001000000000000000000000000001000000000000000100000000000100000000000000000000010000000000000000000000000100000000000000000000000000000000000000000000000000000000000000000000000000000000010000000000000010000000000000000100000110000000000000000000000000000000010000000000000000000010000000000000000000000100 1 00010000000000000000000000001000000000000000000000010000000001000000000000010011000000000000000000100000000000000001001000000000000000000000000000000001000000000000000000000000100000100000000000001000000000000001010000000000010000000000000000001000000000000001000000001000001100001000000000000010000000000010000000000000000000000000010000000000000110000000000001000000000000000000000100000000001001001110000000000000000000100000000000000000001000000000010000000010000000010000000000000000000000000000000100110000001000000000000000000000000001000000000000000100000000000100000000000000000000010000000000000000000000000100000000000000000000000000000000000000000000000000000000000000000000000000000000010000000000000010000000000000000100000110000000000000000000000000000000010000000000000000000010000000000000000000000100

From example above, I want to split to: 1st array: 00010000000000000000000000001000000000000000000000110000000001000000000010010111000000000000000000100000000000000001001000000000000000000000000000000001000000000000000000000000100000100000000000001000000000000001010000000000010000000000000000001000000000000001000000001000001100101000000000000010000000000010000000000000000000000000010000000000000110000000000001000000000000000000000100000000001001001110010000000000000000100000000000000000001000000000010000000010000000010000000000000000000010000000000100110000001000000000000000000000000001000000000000000100000000000100000000000000000000010000000000000000000000000100000000000000000000000000000000000000000000000000000000000000000000000000000000010000000000000010000000000000000100000110000000000000000000000000000000010000000000000000000010000000000000000000000100 2nd array: 00010000000000000000000000001000000000000000000000110000000001000000000010010111000000000000000000100000000000000001001000000000000000000000000000000001000000000000000000000000100000100000000000001000000000000001010000000000010000000000000000001000000000000001000000001000001100101000000000000010000000000010000000000000000000000000010000000000000110000000000001000000000000000000000100000000001001001110010000000000000000100000000000000000001000000000010000000010000000010000000000000000000010000000000100110000001000000000000000000000000001000000000000000100000000000100000000000000000000010000000000000000000000000100000000000000000000000000000000000000000000000000000000000000000000000000000000010000000000000010000000000000000100000110000000000000000000000000000000010000000000000000000010000000000000000000000100

each arrays consist of 800 bytes(from array 0-799). The separator(delimiter), I make it bold 1.


Solution

  • If I'm understanding your question correctly, it looks like you want to read a fixed width flat file.

    Strong suggesion: consider using a library, like flatpack: http://flatpack.sourceforge.net/

    Here are a few other links that might help:

    1) So apparently you've got a "tab delimited file". OK - you can definitely split it into an array of strings with String.split("\t").

    2) In your example example:

    I have txt file consists: 1010101 1 1010111. I want to get 1010101 as array a and 1010111 as array b.

    If the delimiter is always "\t1", that will work. If the delimiter might be "\t2", or "\t1000", then you might want to:

    3) I'm not sure what you mean by "array".

    In your example, the values "1010101" and "1010101" will be two elements in ONE, SINGLE array.

    But this shouldn't be a problem: you can always use myArray[n].charAt(i).

    Or, alternatively, you can always convert the string into a character array:

    char[] charArray = myArray[n].toCharArray();