030-SimpleFileBinding.cpp File Reference

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#include <fiber/bundle/Bundle.hpp>
#include <fiber/finit/FinitAPI.h>
#include <fiber/field/ArrayRef.hpp>
#include <eagle/PhysicalSpace.hpp>
#include <fiber/bundle/Ownership.hpp>

Functions
int	main ()
	File Binding, a way to do Structured Memory Mapping for out-of-core data.

Detailed Description

[← Previous Example] [Next Example → 031-RangedPointCloud.cpp ].

In FiberLib Tutorial

#include <fiber/bundle/Bundle.hpp>
#include <fiber/finit/FinitAPI.h>
 
#include <fiber/field/ArrayRef.hpp>
#include <eagle/PhysicalSpace.hpp>
 
//
// Note that via Ownership functions we can retrieve the Bundle object that
// is associated with some sub-object. In general thus functionality should
// be avoided because a sub-object can be referenced via multiple containers,
// but the "primary" container is available for special cases. This example
// also serves as purpose to check the getPrimaryBundle() function.
//
#include <fiber/bundle/Ownership.hpp>
//
 
 
using namespace Fiber;
using namespace Eagle::PhysicalSpace;
 
/**@brief File Binding, a way to do Structured Memory Mapping for out-of-core data
 
   Demonstrating how to bind a Bundle to a file, then
   adding data to it later on. In contrast, when saving
   a Bundle to a file then data are added first and saved
   in the end. The workflow with the binding feature is
   just other way round - bind first, then add data.
 
   The actual dataset is a set of points with a scalar field on them.
 
 */
int     main()
{
        // Initialize I/O layers (only required for standalone binaries)
        Finit();
 
        //
        // Create a bundle object with a grid at T=1.0, named "DemoGrid", in
        // a three-dimensional cartesian representation, using the default
        // coordinate system.
        //
BundlePtr BP = new Bundle();
 
        unlink("outfile.f5");
 
        Assert(!BP->isBound());
 
        //
        // Save the bundle to a file, even future data
        // that are added to the bundle later. This feature
        // is called "binding" a file to the Bundle.
        //
        BP->bindTo("outfile.f5");
 
        Verbose(0) << "Bundle Binder: " << BP->getBinder();
        Assert(BP->isBound());
 
Representation&myCartesianRepresentation = BP[1.0]["DemoGrid"].makeCartesianRepresentation(3);
 
        Assert(BP->isBound());
 
        Assert(getPrimaryBundle(BP[1.0]));
        Assert(getPrimaryBundle(BP[1.0])->isBound());
 
        Assert(getPrimaryBundle(BP[1.0]["DemoGrid"]));
        Assert(getPrimaryBundle(BP[1.0]["DemoGrid"])->isBound());
 
        Assert(getPrimaryBundle(*BP[1.0]["DemoGrid"].findVertices() ));
        Assert(getPrimaryBundle(*BP[1.0]["DemoGrid"].findVertices())->isBound());
 
        Assert(getPrimaryBundle(myCartesianRepresentation));
        Assert(getPrimaryBundle(myCartesianRepresentation)->isBound());
 
        //
        // Define the size of the grid to be used hereforth
        //
const MultiIndex<3> GridDims = MIndex(11,13,17);
 
        //
        // Create a coordinate field and fill it with values
        //
RefPtr<Field>&Positions = myCartesianRepresentation[ FIBER_POSITIONS ];
 
        Assert(Positions);
        Assert(getPrimaryBundle(*Positions));
        Assert(getPrimaryBundle(*Positions)->isBound());
 
        Verbose(0) << "Positions field is bound to " << getPrimaryBundle(*Positions)->boundUrl();
 
        {
        //
        // Creates a MemArray with a file-write creator, defining
        // the type of the creator at this state.
        //
        ArrayRef<point, 3> Coordinates(GridDims);
 
                for(auto I : GridDims)
                {
                point&P = Coordinates[ I ];
                        P.x() = I[0]*0.83;
                        P.y() = I[1]*0.04*I[1];
                        P.z() = I[2]*0.01*I[2]*I[1];
                }
 
                puts("##################### CREATE CREATOR ######################");fflush(stdout);
 
                if (MemBase::Creator_t
                    CoordinateCreator = Positions->createCreator(Coordinates) )
                {
                        CoordinateCreator->touch();
                }
        }
 
 
#if     1 // optionally enable/disable adding a scalar field
 
        //
        // Define a scalar field called "values" and set numbers
        // to it using some formula based on the indices, just to
        // get something non-trivial here.
        //
RefPtr<Field>&Values = myCartesianRepresentation["values"];
        {
        ArrayRef<double, 3> GridValues(GridDims);
 
                for(MultiIndex<3> I : GridDims)
                {
                double& value = GridValues[ I ];
                        value = (I[0]*0.3)*(I[0]*0.3) +
                                (I[1]*0.2)*(I[0]*0.2) -
                                (I[2]*0.1)*(I[2]*0.1);
                }
 
                if (MemBase::Creator_t
                    ValueCreator = Values->createCreator(GridValues) )
                {
                        ValueCreator->touch();
                }
        }
#endif
 
        return 0;
}

Function Documentation

main()

int main

(

)

File Binding, a way to do Structured Memory Mapping for out-of-core data.

Demonstrating how to bind a Bundle to a file, then adding data to it later on. In contrast, when saving a Bundle to a file then data are added first and saved in the end. The workflow with the binding feature is just other way round - bind first, then add data.

The actual dataset is a set of points with a scalar field on them.