Golang data.Slice類代碼示例

func normalize(f *data.Slice) {
	a := f.Vectors()
	maxnorm := 0.
	for i := range a[0] {
		for j := range a[0][i] {
			for k := range a[0][i][j] {

				x, y, z := a[0][i][j][k], a[1][i][j][k], a[2][i][j][k]
				norm := math.Sqrt(float64(x*x + y*y + z*z))
				if norm > maxnorm {
					maxnorm = norm
				}

			}
		}
	}
	factor := float32(1 / maxnorm)

	for i := range a[0] {
		for j := range a[0][i] {
			for k := range a[0][i][j] {
				a[0][i][j][k] *= factor
				a[1][i][j][k] *= factor
				a[2][i][j][k] *= factor

			}
		}
	}
}

func readOVF1DataBinary8(in io.Reader, t *data.Slice) {
	size := t.Size()
	data := t.Tensors()

	// OOMMF requires this number to be first to check the format
	var controlnumber float64
	// OVF 1.0 is network byte order (MSB)
	binary.Read(in, binary.BigEndian, &controlnumber)

	if controlnumber != OVF_CONTROL_NUMBER_8 {
		panic("invalid OVF1 control number: " + fmt.Sprint(controlnumber))
	}

	var tmp float64
	for iz := 0; iz < size[Z]; iz++ {
		for iy := 0; iy < size[Y]; iy++ {
			for ix := 0; ix < size[X]; ix++ {
				for c := 0; c < 3; c++ {
					err := binary.Read(in, binary.BigEndian, &tmp)
					if err != nil {
						panic(err)
					}
					data[c][iz][iy][ix] = float32(tmp)
				}
			}
		}
	}
}

func (b *magnetization) SetArray(src *data.Slice) {
	if src.Size() != b.Mesh().Size() {
		src = data.Resample(src, b.Mesh().Size())
	}
	data.Copy(b.Buffer(), src)
	M.normalize()
}

func assureGPU(s *data.Slice) *data.Slice {
	if s.GPUAccess() {
		return s
	} else {
		return cuda.GPUCopy(s)
	}
}

func dumpGnuplot(f *data.Slice, m data.Meta, out io.Writer) {
	buf := bufio.NewWriter(out)
	defer buf.Flush()

	data := f.Tensors()
	cellsize := m.CellSize
	// If no cell size is set, use generic cell index.
	if cellsize == [3]float64{0, 0, 0} {
		cellsize = [3]float64{1, 1, 1}
	}
	ncomp := f.NComp()

	for iz := range data[0] {
		z := float64(iz) * cellsize[Z]
		for iy := range data[0][iz] {
			y := float64(iy) * cellsize[Y]
			for ix := range data[0][iz][iy] {
				x := float64(ix) * cellsize[X]
				fmt.Fprint(buf, x, DELIM, y, DELIM, z, DELIM)
				for c := 0; c < ncomp-1; c++ {
					fmt.Fprint(buf, data[c][iz][iy][ix], DELIM)
				}
				fmt.Fprint(buf, data[ncomp-1][iz][iy][ix])
				fmt.Fprint(buf, "\n")
			}
			fmt.Fprint(buf, "\n")
		}
	}
}

// dst += LUT[region], for vectors. Used to add terms to excitation.
func RegionAddV(dst *data.Slice, lut LUTPtrs, regions *Bytes) {
	util.Argument(dst.NComp() == 3)
	N := dst.Len()
	cfg := make1DConf(N)
	k_regionaddv_async(dst.DevPtr(X), dst.DevPtr(Y), dst.DevPtr(Z),
		lut[X], lut[Y], lut[Z], regions.Ptr, N, cfg)
}

// Write the slice to out in binary format. Add time stamp.
func Write(out io.Writer, s *data.Slice, info data.Meta) error {
	w := newWriter(out)

	// Writes the header.
	w.writeString(MAGIC)
	w.writeUInt64(uint64(s.NComp()))
	size := s.Size()
	w.writeUInt64(uint64(size[2])) // backwards compatible coordinates!
	w.writeUInt64(uint64(size[1]))
	w.writeUInt64(uint64(size[0]))
	cell := info.CellSize
	w.writeFloat64(cell[2])
	w.writeFloat64(cell[1])
	w.writeFloat64(cell[0])
	w.writeString(info.MeshUnit)
	w.writeFloat64(info.Time)
	w.writeString("s") // time unit
	w.writeString(info.Name)
	w.writeString(info.Unit)
	w.writeUInt64(4) // precission

	// return header write error before writing data
	if w.err != nil {
		return w.err
	}

	w.writeData(s)
	w.writeHash()
	return w.err
}

func crop(f *data.Slice) {
	N := f.Size()
	// default ranges
	x1, x2 := 0, N[X]
	y1, y2 := 0, N[Y]
	z1, z2 := 0, N[Z]
	havework := false

	if *flag_cropz != "" {
		z1, z2 = parseRange(*flag_cropz, N[Z])
		havework = true
	}
	if *flag_cropy != "" {
		y1, y2 = parseRange(*flag_cropy, N[Y])
		havework = true
	}
	if *flag_cropx != "" {
		x1, x2 = parseRange(*flag_cropx, N[X])
		havework = true
	}

	if havework {
		*f = *data.Crop(f, x1, x2, y1, y2, z1, z2)
	}
}

// Calculate the demag field of m * vol * Bsat, store result in B.
// 	m:    magnetization normalized to unit length
// 	vol:  unitless mask used to scale m's length, may be nil
// 	Bsat: saturation magnetization in Tesla
// 	B:    resulting demag field, in Tesla
func (c *DemagConvolution) Exec(B, m, vol *data.Slice, Bsat LUTPtr, regions *Bytes) {
	util.Argument(B.Size() == c.inputSize && m.Size() == c.inputSize)
	if c.is2D() {
		c.exec2D(B, m, vol, Bsat, regions)
	} else {
		c.exec3D(B, m, vol, Bsat, regions)
	}
}

func writeVTKHeader(out io.Writer, q *data.Slice) (err error) {
	gridsize := q.Size()
	_, err = fmt.Fprintln(out, "<?xml version=\"1.0\"?>")
	_, err = fmt.Fprintln(out, "<VTKFile type=\"StructuredGrid\" version=\"0.1\" byte_order=\"LittleEndian\">")
	_, err = fmt.Fprintf(out, "\t<StructuredGrid WholeExtent=\"0 %d 0 %d 0 %d\">\n", gridsize[0]-1, gridsize[1]-1, gridsize[2]-1)
	_, err = fmt.Fprintf(out, "\t\t<Piece Extent=\"0 %d 0 %d 0 %d\">\n", gridsize[0]-1, gridsize[1]-1, gridsize[2]-1)
	return
}

// Calculate the demag field of m * vol * Bsat, store result in B.
// 	m:    magnetization normalized to unit length
// 	vol:  unitless mask used to scale m's length, may be nil
// 	Bsat: saturation magnetization in Tesla
// 	B:    resulting demag field, in Tesla
func (c *DemagConvolution) Exec(B, m, vol *data.Slice, Msat MSlice) {
	util.Argument(B.Size() == c.inputSize && m.Size() == c.inputSize)
	if c.is2D() {
		c.exec2D(B, m, vol, Msat)
	} else {
		c.exec3D(B, m, vol, Msat)
	}
}

// Set Bth to thermal noise (Brown).
// see temperature.cu
func SetTemperature(Bth, noise *data.Slice, temp_red LUTPtr, k2mu0_VgammaDt float64, regions *Bytes) {
	util.Argument(Bth.NComp() == 1 && noise.NComp() == 1)

	N := Bth.Len()
	cfg := make1DConf(N)

	k_settemperature_async(Bth.DevPtr(0), noise.DevPtr(0), float32(k2mu0_VgammaDt), unsafe.Pointer(temp_red),
		regions.Ptr, N, cfg)
}

func writeOVF2Header(out io.Writer, q *data.Slice, meta data.Meta) {
	gridsize := q.Size()
	cellsize := meta.CellSize

	fmt.Fprintln(out, "# OOMMF OVF 2.0")
	hdr(out, "Segment count", "1")
	hdr(out, "Begin", "Segment")
	hdr(out, "Begin", "Header")

	hdr(out, "Title", meta.Name)
	hdr(out, "meshtype", "rectangular")
	hdr(out, "meshunit", "m")

	hdr(out, "xmin", 0)
	hdr(out, "ymin", 0)
	hdr(out, "zmin", 0)

	hdr(out, "xmax", cellsize[X]*float64(gridsize[X]))
	hdr(out, "ymax", cellsize[Y]*float64(gridsize[Y]))
	hdr(out, "zmax", cellsize[Z]*float64(gridsize[Z]))

	name := meta.Name
	var labels []interface{}
	if q.NComp() == 1 {
		labels = []interface{}{name}
	} else {
		for i := 0; i < q.NComp(); i++ {
			labels = append(labels, name+"_"+string('x'+i))
		}
	}
	hdr(out, "valuedim", q.NComp())
	hdr(out, "valuelabels", labels...) // TODO
	unit := meta.Unit
	if unit == "" {
		unit = "1"
	}
	if q.NComp() == 1 {
		hdr(out, "valueunits", unit)
	} else {
		hdr(out, "valueunits", unit, unit, unit)
	}

	// We don't really have stages
	//fmt.Fprintln(out, "# Desc: Stage simulation time: ", meta.TimeStep, " s") // TODO
	hdr(out, "Desc", "Total simulation time: ", meta.Time, " s")

	hdr(out, "xbase", cellsize[X]/2)
	hdr(out, "ybase", cellsize[Y]/2)
	hdr(out, "zbase", cellsize[Z]/2)
	hdr(out, "xnodes", gridsize[X])
	hdr(out, "ynodes", gridsize[Y])
	hdr(out, "znodes", gridsize[Z])
	hdr(out, "xstepsize", cellsize[X])
	hdr(out, "ystepsize", cellsize[Y])
	hdr(out, "zstepsize", cellsize[Z])
	hdr(out, "End", "Header")
}

// Finds the average exchange strength around each cell, for debugging.
func ExchangeDecode(dst *data.Slice, Aex_red SymmLUT, regions *Bytes, mesh *data.Mesh) {
	c := mesh.CellSize()
	wx := float32(2 * 1e-18 / (c[X] * c[X]))
	wy := float32(2 * 1e-18 / (c[Y] * c[Y]))
	wz := float32(2 * 1e-18 / (c[Z] * c[Z]))
	N := mesh.Size()
	pbc := mesh.PBC_code()
	cfg := make3DConf(N)
	k_exchangedecode_async(dst.DevPtr(0), unsafe.Pointer(Aex_red), regions.Ptr, wx, wy, wz, N[X], N[Y], N[Z], pbc, cfg)
}

func checkNaN(s *data.Slice, name string) {
	h := s.Host()
	for _, h := range h {
		for _, v := range h {
			if math.IsNaN(float64(v)) || math.IsInf(float64(v), 0) {
				util.Fatal("NaN or Inf in", name)
			}
		}
	}
}