[clfft] 31/107: 3d fft example

[Ghislain Vaillant]

This is an automated email from the git hooks/post-receive script.

ghisvail-guest pushed a commit to branch master
in repository clfft.

commit e172b3e211cf97dfda0569b8069000bdcd960f19
Author: Pradeep <pradeep at arrayfire.com>
Date:   Mon Mar 9 12:22:34 2015 -0400

    3d fft example
---
 src/examples/fft3d.c | 154 +++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 154 insertions(+)

diff --git a/src/examples/fft3d.c b/src/examples/fft3d.c
new file mode 100644
index 0000000..d5c4eb5
--- /dev/null
+++ b/src/examples/fft3d.c
@@ -0,0 +1,154 @@
+/* ************************************************************************
+ * Copyright 2013 Advanced Micro Devices, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ************************************************************************/
+
+#include <stdio.h>
+#include <stdlib.h>
+
+/* No need to explicitely include the OpenCL headers */
+#include <clFFT.h>
+
+int main( void )
+{
+    cl_int err;
+    cl_platform_id platform = 0;
+    cl_device_id device = 0;
+    cl_context_properties props[3] = { CL_CONTEXT_PLATFORM, 0, 0 };
+    cl_context ctx = 0;
+    cl_command_queue queue = 0;
+    cl_mem bufX;
+    float *X;
+    cl_event event = NULL;
+    int ret = 0;
+
+    const size_t N0 = 4, N1 = 4, N2 = 4;
+    char platform_name[128];
+    char device_name[128];
+
+    /* FFT library realted declarations */
+    clfftPlanHandle planHandle;
+    clfftDim dim = CLFFT_3D;
+    size_t clLengths[3] = {N0, N1, N2};
+
+    /* Setup OpenCL environment. */
+    err = clGetPlatformIDs( 1, &platform, NULL );
+
+    size_t ret_param_size = 0;
+    err = clGetPlatformInfo(platform, CL_PLATFORM_NAME,
+            sizeof(platform_name), platform_name,
+            &ret_param_size);
+    printf("Platform found: %s\n", platform_name);
+
+    err = clGetDeviceIDs( platform, CL_DEVICE_TYPE_DEFAULT, 1, &device, NULL );
+
+    err = clGetDeviceInfo(device, CL_DEVICE_NAME,
+            sizeof(device_name), device_name,
+            &ret_param_size);
+    printf("Device found on the above platform: %s\n", device_name);
+
+    props[1] = (cl_context_properties)platform;
+    ctx = clCreateContext( props, 1, &device, NULL, NULL, &err );
+    queue = clCreateCommandQueue( ctx, device, 0, &err );
+
+    /* Setup clFFT. */
+    clfftSetupData fftSetup;
+    err = clfftInitSetupData(&fftSetup);
+    err = clfftSetup(&fftSetup);
+
+    /* Allocate host & initialize data. */
+    /* Only allocation shown for simplicity. */
+    size_t buffer_size  = N0 * N1 * N2 * 2 * sizeof(*X);
+    X = (float *)malloc(buffer_size);
+
+    /* print input array just using the
+     * indices to fill the array with data */
+    printf("\nPerforming fft on an two dimensional array of size N0 x N1 x N2 : %ld x %ld x %ld\n", N0, N1, N2);
+    int i, j, k;
+    i = j = k = 0;
+    for (i=0; i<N0; ++i) {
+        for (j=0; j<N1; ++j) {
+            for (k=0; k<N2; ++k) {
+                float x = 0.0f;
+                float y = 0.0f;
+                if (i==0 && j==0 && k==0) {
+                    x = y = 0.5f;
+                }
+                unsigned idx = 2*(k+j*N1+i*N0*N1);
+                X[idx] = x;
+                X[idx+1] = y;
+                printf("(%f, %f) ", X[idx], X[idx+1]);
+            }
+            printf("\n");
+        }
+        printf("\n");
+    }
+
+    /* Prepare OpenCL memory objects and place data inside them. */
+    bufX = clCreateBuffer( ctx, CL_MEM_READ_WRITE, buffer_size, NULL, &err );
+
+    err = clEnqueueWriteBuffer( queue, bufX, CL_TRUE, 0, buffer_size, X, 0, NULL, NULL );
+
+    /* Create a default plan for a complex FFT. */
+    err = clfftCreateDefaultPlan(&planHandle, ctx, dim, clLengths);
+
+    /* Set plan parameters. */
+    err = clfftSetPlanPrecision(planHandle, CLFFT_SINGLE);
+    err = clfftSetLayout(planHandle, CLFFT_COMPLEX_INTERLEAVED, CLFFT_COMPLEX_INTERLEAVED);
+    err = clfftSetResultLocation(planHandle, CLFFT_INPLACE);
+
+    /* Bake the plan. */
+    err = clfftBakePlan(planHandle, 1, &queue, NULL, NULL);
+
+    /* Execute the plan. */
+    err = clfftEnqueueTransform(planHandle, CLFFT_FORWARD, 1, &queue, 0, NULL, NULL, &bufX, NULL, NULL);
+
+    /* Wait for calculations to be finished. */
+    err = clFinish(queue);
+
+    /* Fetch results of calculations. */
+    err = clEnqueueReadBuffer( queue, bufX, CL_TRUE, 0, buffer_size, X, 0, NULL, NULL );
+
+    /* print output array */
+    printf("\n\nfft result: \n");
+    i = j = k = 0;
+    for (i=0; i<N0; ++i) {
+        for (j=0; j<N1; ++j) {
+            for (k=0; k<N2; ++k) {
+                unsigned idx = 2*(k+j*N1+i*N0*N1);
+                printf("(%f, %f) ", X[idx], X[idx+1]);
+            }
+            printf("\n");
+        }
+        printf("\n");
+    }
+    printf("\n");
+
+    /* Release OpenCL memory objects. */
+    clReleaseMemObject( bufX );
+
+    free(X);
+
+    /* Release the plan. */
+    err = clfftDestroyPlan( &planHandle );
+
+    /* Release clFFT library. */
+    clfftTeardown( );
+
+    /* Release OpenCL working objects. */
+    clReleaseCommandQueue( queue );
+    clReleaseContext( ctx );
+
+    return ret;
+}

-- 
Alioth's /usr/local/bin/git-commit-notice on /srv/git.debian.org/git/debian-science/packages/clfft.git