doc: section basic examples

doc/starpu.texi

@@ -1599,7 +1599,7 @@ LDFLAGS         +=      $$(pkg-config --libs libstarpu)
 * Required Headers::            
 * Defining a Codelet::          
 * Submitting a Task::           
-* Execution::                   
+* Execution of Hello World::    
 @end menu
 
 In this section, we show how to implement a simple program that submits a task to StarPU.
@@ -1747,8 +1747,8 @@ synchronous: the @code{starpu_task_submit} function will not return until the
 task was executed. Note that the @code{starpu_shutdown} method does not
 guarantee that asynchronous tasks have been executed before it returns.
 
-@node Execution
-@subsection Execution
+@node Execution of Hello World
+@subsection Execution of Hello World
 
 @example
 % make helloWorld
@@ -1765,6 +1765,14 @@ The previous example has shown how to submit tasks. In this section,
 we show how StarPU tasks can manipulate data. The full source code for
 this example is given in @xref{Full source code for the 'Scaling a Vector' example}.
 
+@menu
+* Source code of Vector Scaling::  
+* Execution of Vector Scaling::  
+@end menu
+
+@node Source code of Vector Scaling
+@subsection Source code of Vector Scaling
+
 Programmers can describe the data layout of their application so that StarPU is
 responsible for enforcing data coherency and availability across the machine.
 Instead of handling complex (and non-portable) mechanisms to perform data
@@ -1784,10 +1792,10 @@ The following lines show how to declare an array of @code{NX} elements of type
 
 @cartouche
 @example
-float tab[NX];
+float vector[NX];
 
 starpu_data_handle tab_handle;
-starpu_vector_data_register(&tab_handle, 0, tab, NX, sizeof(float));
+starpu_vector_data_register(&tab_handle, 0, vector, NX, sizeof(float));
 @end example
 @end cartouche
 
@@ -1866,6 +1874,16 @@ interface}, the location of the vector (resp. its length) is accessible in the
 read-write fashion, any modification will automatically affect future accesses
 to this vector made by other tasks.
 
+@node Execution of Vector Scaling
+@subsection Execution of Vector Scaling
+
+@example
+% make vector
+cc $(pkg-config --cflags libstarpu)  $(pkg-config --libs libstarpu)  vector.c   -o vector
+% ./vector
+0.000000 3.000000 6.000000 9.000000 12.000000
+@end example
+
 @node Vector Scaling on an Hybrid CPU/GPU Machine
 @section Vector Scaling on an Hybrid CPU/GPU Machine
 
@@ -1873,12 +1891,12 @@ Contrary to the previous examples, the task submitted in this example may not
 only be executed by the CPUs, but also by a CUDA device.
 
 @menu
-* Source code::                 Source of the StarPU application
-* Compilation and execution::   Executing the StarPU application
+* Source code of Hybrid Vector Scaling::  
+* Compilation and execution of Hybrid Vector Scaling::  
 @end menu
 
-@node Source code
-@subsection Source code
+@node Source code of Hybrid Vector Scaling
+@subsection Source code of Hybrid Vector Scaling
 
 The CUDA implementation can be written as follows. It needs to be
 compiled with a CUDA compiler such as nvcc, the NVIDIA CUDA compiler
@@ -2005,8 +2023,8 @@ int main(int argc, char **argv)
 @end example
 @end cartouche
 
-@node Compilation and execution
-@subsection Compilation and execution
+@node Compilation and execution of Hybrid Vector Scaling
+@subsection Compilation and execution of Hybrid Vector Scaling
 
 The Makefile given at the beginning of the section must be extended to
 give the rules to compile the CUDA source code.
@@ -2095,16 +2113,18 @@ starpu_codelet cl = @{
     .nbuffers = 1
 @};
 
-#define NX 10
+#define NX 5
 
 int main(int argc, char **argv)
 @{
-    float tab[NX];
+    float vector[NX];
     starpu_data_handle tab_handle;
     float factor = 3.0;
+    int i;
 
     starpu_init(NULL);
-    starpu_vector_data_register(&tab_handle, 0, (uintptr_t)tab, NX, sizeof(float));
+    for(i=0 ; i<NX; i++) vector[i] = i;
+    starpu_vector_data_register(&tab_handle, 0, (uintptr_t)vector, NX, sizeof(float));
 
     struct starpu_task *task = starpu_task_create();
     task->cl = &cl;
@@ -2116,6 +2136,11 @@ int main(int argc, char **argv)
 
     starpu_task_submit(task);
 
+    for(i=0 ; i<NX ; i++) @{
+        fprintf(stderr, "%f ", vector[i]);
+    @}
+    fprintf(stderr, "\n");
+
     starpu_shutdown();
     return 0;
 @}