Golang Slice.Tensors方法代碼示例

// Writes data in OMF Binary 4 format
func writeOVF1Binary4(out io.Writer, array *data.Slice) (err error) {
	data := array.Tensors()
	gridsize := array.Size()

	var bytes []byte

	// OOMMF requires this number to be first to check the format
	var controlnumber float32 = OVF_CONTROL_NUMBER_4
	// Conversion form float32 [4]byte in big-endian
	// Inlined for performance, terabytes of data will pass here...
	bytes = (*[4]byte)(unsafe.Pointer(&controlnumber))[:]
	bytes[0], bytes[1], bytes[2], bytes[3] = bytes[3], bytes[2], bytes[1], bytes[0] // swap endianess
	_, err = out.Write(bytes)

	ncomp := array.NComp()
	for iz := 0; iz < gridsize[Z]; iz++ {
		for iy := 0; iy < gridsize[Y]; iy++ {
			for ix := 0; ix < gridsize[X]; ix++ {
				for c := 0; c < ncomp; c++ {
					// dirty conversion from float32 to [4]byte
					bytes = (*[4]byte)(unsafe.Pointer(&data[c][iz][iy][ix]))[:]
					bytes[0], bytes[1], bytes[2], bytes[3] = bytes[3], bytes[2], bytes[1], bytes[0]
					out.Write(bytes)
				}
			}
		}
	}
	return
}

func writeOVF2DataBinary4(out io.Writer, array *data.Slice) {

	//w.count(w.out.Write((*(*[1<<31 - 1]byte)(unsafe.Pointer(&list[0])))[0 : 4*len(list)])) // (shortcut)

	data := array.Tensors()
	size := array.Size()

	var bytes []byte

	// OOMMF requires this number to be first to check the format
	var controlnumber float32 = OVF_CONTROL_NUMBER_4
	bytes = (*[4]byte)(unsafe.Pointer(&controlnumber))[:]
	out.Write(bytes)

	ncomp := array.NComp()
	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 < ncomp; c++ {
					bytes = (*[4]byte)(unsafe.Pointer(&data[c][iz][iy][ix]))[:]
					out.Write(bytes)
				}
			}
		}
	}
}

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")
		}
	}
}

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)
				}
			}
		}
	}
}

// Writes the data.
func (w *writer) writeData(array *data.Slice) {
	data := array.Tensors()
	size := array.Size()

	ncomp := array.NComp()
	for c := 0; c < ncomp; c++ {
		for iz := 0; iz < size[2]; iz++ {
			for iy := 0; iy < size[1]; iy++ {
				for ix := 0; ix < size[0]; ix++ {
					w.writeFloat32(data[c][iz][iy][ix])
				}
			}
		}
	}
}

// comma-separated values
func dumpCSV(f *data.Slice, info data.Meta, out io.Writer) {
	f2 := ", " + *flag_format
	a := f.Tensors()
	for _, a := range a {
		for _, a := range a {
			for _, a := range a {
				fmt.Fprintf(out, *flag_format, a[0])
				for i := 1; i < len(a); i++ {
					fmt.Fprintf(out, f2, a[i])
				}
				fmt.Fprintln(out)
			}
			fmt.Fprintln(out)
		}
	}
}

// read data block in text format, for OVF1 and OVF2
func readOVFDataText(in io.Reader, t *data.Slice) {
	size := t.Size()
	data := t.Tensors()
	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 < t.NComp(); c++ {
					_, err := fmt.Fscan(in, &data[c][iz][iy][ix])
					if err != nil {
						panic(err)
					}
				}
			}
		}
	}
}

// write data block in text format, for OVF1 and OVF2
func writeOVFText(out io.Writer, tens *data.Slice) (err error) {
	data := tens.Tensors()
	gridsize := tens.Size()
	ncomp := tens.NComp()

	// Here we loop over X,Y,Z, not Z,Y,X, because
	// internal in C-order == external in Fortran-order
	for iz := 0; iz < gridsize[Z]; iz++ {
		for iy := 0; iy < gridsize[Y]; iy++ {
			for ix := 0; ix < gridsize[X]; ix++ {
				for c := 0; c < ncomp; c++ {
					_, err = fmt.Fprint(out, data[c][iz][iy][ix], " ")
				}
				_, err = fmt.Fprint(out, "\n")
			}
		}
	}
	return
}

func readOVF2DataBinary8(in io.Reader, array *data.Slice) {
	size := array.Size()
	data := array.Tensors()

	// OOMMF requires this number to be first to check the format
	controlnumber := readFloat64(in)
	if controlnumber != OVF_CONTROL_NUMBER_8 {
		panic("invalid OVF2 control number: " + fmt.Sprint(controlnumber))
	}

	ncomp := array.NComp()
	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 < ncomp; c++ {
					data[c][iz][iy][ix] = float32(readFloat64(in))
				}
			}
		}
	}
}

func dumpJSON(f *data.Slice, info data.Meta, out io.Writer) {
	w := json.NewEncoder(out)
	w.Encode(f.Tensors())
}

// does not output to out, just prints to stdout
func show(f *data.Slice, info data.Meta, out io.Writer) {
	fmt.Println(info)
	util.Fprintf(os.Stdout, *flag_format, f.Tensors())
}

func writeVTKCellData(out io.Writer, q *data.Slice, meta data.Meta, dataformat string) (err error) {
	N := q.NComp()
	data := q.Tensors()
	switch N {
	case 1:
		fmt.Fprintf(out, "\t\t\t<PointData Scalars=\"%s\">\n", meta.Name)
		fmt.Fprintf(out, "\t\t\t\t<DataArray type=\"Float32\" Name=\"%s\" NumberOfComponents=\"%d\" format=\"%s\">\n\t\t\t\t\t", meta.Name, N, dataformat)
	case 3:
		fmt.Fprintf(out, "\t\t\t<PointData Vectors=\"%s\">\n", meta.Name)
		fmt.Fprintf(out, "\t\t\t\t<DataArray type=\"Float32\" Name=\"%s\" NumberOfComponents=\"%d\" format=\"%s\">\n\t\t\t\t\t", meta.Name, N, dataformat)
	case 6, 9:
		fmt.Fprintf(out, "\t\t\t<PointData Tensors=\"%s\">\n", meta.Name)
		fmt.Fprintf(out, "\t\t\t\t<DataArray type=\"Float32\" Name=\"%s\" NumberOfComponents=\"%d\" format=\"%s\">\n\t\t\t\t\t", meta.Name, 9, dataformat) // must be 9!
	default:
		log.Fatalf("vtk: cannot handle %v components", N)
	}
	gridsize := q.Size()
	switch dataformat {
	case "ascii":
		for k := 0; k < gridsize[2]; k++ {
			for j := 0; j < gridsize[1]; j++ {
				for i := 0; i < gridsize[0]; i++ {
					// if symmetric tensor manage it appart to write the full 9 components
					if N == 6 {
						fmt.Fprint(out, data[0][k][j][i], " ")
						fmt.Fprint(out, data[1][k][j][i], " ")
						fmt.Fprint(out, data[2][k][j][i], " ")
						fmt.Fprint(out, data[1][k][j][i], " ")
						fmt.Fprint(out, data[3][k][j][i], " ")
						fmt.Fprint(out, data[4][k][j][i], " ")
						fmt.Fprint(out, data[2][k][j][i], " ")
						fmt.Fprint(out, data[4][k][j][i], " ")
						fmt.Fprint(out, data[5][k][j][i], " ")
					} else {
						for c := 0; c < N; c++ {
							fmt.Fprint(out, data[c][k][j][i], " ")
						}
					}
				}
			}
		}
	case "binary":
		// Inlined for performance, terabytes of data will pass here...
		buffer := new(bytes.Buffer)
		for k := 0; k < gridsize[2]; k++ {
			for j := 0; j < gridsize[1]; j++ {
				for i := 0; i < gridsize[0]; i++ {
					// if symmetric tensor manage it appart to write the full 9 components
					if N == 6 {
						binary.Write(buffer, binary.LittleEndian, data[0][k][j][i])
						binary.Write(buffer, binary.LittleEndian, data[1][k][j][i])
						binary.Write(buffer, binary.LittleEndian, data[2][k][j][i])
						binary.Write(buffer, binary.LittleEndian, data[1][k][j][i])
						binary.Write(buffer, binary.LittleEndian, data[3][k][j][i])
						binary.Write(buffer, binary.LittleEndian, data[4][k][j][i])
						binary.Write(buffer, binary.LittleEndian, data[2][k][j][i])
						binary.Write(buffer, binary.LittleEndian, data[4][k][j][i])
						binary.Write(buffer, binary.LittleEndian, data[5][k][j][i])
					} else {
						for c := 0; c < N; c++ {
							binary.Write(buffer, binary.LittleEndian, data[c][k][j][i])
						}
					}
				}
			}
		}
		b64len := uint32(len(buffer.Bytes()))
		bufLen := new(bytes.Buffer)
		binary.Write(bufLen, binary.LittleEndian, b64len)
		base64out := base64.NewEncoder(base64.StdEncoding, out)
		base64out.Write(bufLen.Bytes())
		base64out.Write(buffer.Bytes())
		base64out.Close()
	default:
		panic(fmt.Errorf("vtk: illegal data format " + dataformat + ". Options are: ascii, binary"))
	}

	fmt.Fprintln(out, "\n\t\t\t\t</DataArray>")
	fmt.Fprintln(out, "\t\t\t</PointData>")
	return
}