Documentation ¶
Overview ¶
Package rtree contains the interfaces and types to decode, read, concatenate and iterate over ROOT Trees.
Example (CreateEventNtupleFullSplit) ¶
package main import ( "bytes" "fmt" "log" "reflect" "go-hep.org/x/hep/groot" "go-hep.org/x/hep/groot/rcmd" "go-hep.org/x/hep/groot/rdict" "go-hep.org/x/hep/groot/rtree" ) func main() { type P4 struct { Px float64 `groot:"px"` Py float64 `groot:"py"` Pz float64 `groot:"pz"` E float64 `groot:"ene"` } type Particle struct { ID int32 `groot:"id"` P4 P4 `groot:"p4"` } type Event struct { I32 int32 `groot:"i32"` F64 float64 `groot:"f64"` Str string `groot:"str"` Arr [5]float64 `groot:"arr"` Sli []float64 `groot:"sli"` P4 P4 `groot:"p4"` Ps []Particle `groot:"mc"` } // register streamers for _, typ := range []reflect.Type{ reflect.TypeOf(P4{}), reflect.TypeOf(Particle{}), reflect.TypeOf(Event{}), } { rdict.StreamerInfos.Add(rdict.StreamerOf( rdict.StreamerInfos, typ, )) } const ( fname = "../testdata/groot-event-ntuple-fullsplit.root" nevts = 5 ) func() { f, err := groot.Create(fname) if err != nil { log.Fatalf("could not create ROOT file: %+v", err) } defer f.Close() var ( evt Event wvars = rtree.WriteVarsFromStruct(&evt) ) tree, err := rtree.NewWriter(f, "mytree", wvars) if err != nil { log.Fatalf("could not create tree writer: %+v", err) } defer tree.Close() fmt.Printf("-- created tree %q:\n", tree.Name()) for i, b := range tree.Branches() { fmt.Printf("branch[%d]: name=%q, title=%q\n", i, b.Name(), b.Title()) } for i := 0; i < nevts; i++ { evt.I32 = int32(i) evt.F64 = float64(i) evt.Str = fmt.Sprintf("evt-%0d", i) evt.Arr = [5]float64{float64(i), float64(i + 1), float64(i + 2), float64(i + 3), float64(i + 4)} evt.Sli = []float64{float64(i), float64(i + 1), float64(i + 2), float64(i + 3), float64(i + 4)}[:i] evt.P4 = P4{Px: float64(i), Py: float64(i + 1), Pz: float64(i + 2), E: float64(i + 3)} evt.Ps = []Particle{ {ID: int32(i), P4: evt.P4}, {ID: int32(i + 1), P4: evt.P4}, {ID: int32(i + 2), P4: evt.P4}, {ID: int32(i + 3), P4: evt.P4}, {ID: int32(i + 4), P4: evt.P4}, }[:i] _, err = tree.Write() if err != nil { log.Fatalf("could not write event %d: %+v", i, err) } } fmt.Printf("-- filled tree with %d entries\n", tree.Entries()) err = tree.Close() if err != nil { log.Fatalf("could not write tree: %+v", err) } err = f.Close() if err != nil { log.Fatalf("could not close tree: %+v", err) } }() { fmt.Printf("-- read back ROOT file\n") out := new(bytes.Buffer) err := rcmd.List(out, fname, rcmd.ListTrees(true)) if err != nil { log.Fatalf("could not list ROOT file content: %+v", err) } fmt.Printf("%s\n", out.String()) } { var ( deep = true filter = func(name string) bool { return true } ) out := new(bytes.Buffer) err := rcmd.Dump(out, fname, deep, filter) if err != nil { log.Fatalf("could not dump ROOT file: %+v", err) } fmt.Printf("%s\n", out.String()) } }
Output: -- created tree "mytree": branch[0]: name="i32", title="i32/I" branch[1]: name="f64", title="f64/D" branch[2]: name="str", title="str/C" branch[3]: name="arr", title="arr[5]/D" branch[4]: name="sli", title="sli" branch[5]: name="p4", title="p4" branch[6]: name="mc", title="mc" -- filled tree with 5 entries -- read back ROOT file === [../testdata/groot-event-ntuple-fullsplit.root] === version: 62202 TTree mytree (entries=5) i32 "i32/I" TBranch f64 "f64/D" TBranch str "str/C" TBranch arr "arr[5]/D" TBranch sli "sli" TBranchElement p4 "p4" TBranchElement mc "mc" TBranchElement key[000]: mytree;1 "" (TTree) [000][i32]: 0 [000][f64]: 0 [000][str]: evt-0 [000][arr]: [0 1 2 3 4] [000][sli]: [] [000][p4]: {0 1 2 3} [000][mc]: [] [001][i32]: 1 [001][f64]: 1 [001][str]: evt-1 [001][arr]: [1 2 3 4 5] [001][sli]: [1] [001][p4]: {1 2 3 4} [001][mc]: [{1 {1 2 3 4}}] [002][i32]: 2 [002][f64]: 2 [002][str]: evt-2 [002][arr]: [2 3 4 5 6] [002][sli]: [2 3] [002][p4]: {2 3 4 5} [002][mc]: [{2 {2 3 4 5}} {3 {2 3 4 5}}] [003][i32]: 3 [003][f64]: 3 [003][str]: evt-3 [003][arr]: [3 4 5 6 7] [003][sli]: [3 4 5] [003][p4]: {3 4 5 6} [003][mc]: [{3 {3 4 5 6}} {4 {3 4 5 6}} {5 {3 4 5 6}}] [004][i32]: 4 [004][f64]: 4 [004][str]: evt-4 [004][arr]: [4 5 6 7 8] [004][sli]: [4 5 6 7] [004][p4]: {4 5 6 7} [004][mc]: [{4 {4 5 6 7}} {5 {4 5 6 7}} {6 {4 5 6 7}} {7 {4 5 6 7}}]
Example (CreateEventNtupleNoSplit) ¶
package main import ( "bytes" "fmt" "log" "reflect" "go-hep.org/x/hep/groot" "go-hep.org/x/hep/groot/rcmd" "go-hep.org/x/hep/groot/rdict" "go-hep.org/x/hep/groot/rtree" ) func main() { type P4 struct { Px float64 `groot:"px"` Py float64 `groot:"py"` Pz float64 `groot:"pz"` E float64 `groot:"ene"` } type Particle struct { ID int32 `groot:"id"` P4 P4 `groot:"p4"` } type Event struct { I32 int32 `groot:"i32"` F64 float64 `groot:"f64"` Str string `groot:"str"` Arr [5]float64 `groot:"arr"` Sli []float64 `groot:"sli"` P4 P4 `groot:"p4"` Ps []Particle `groot:"mc"` } // register streamers for _, typ := range []reflect.Type{ reflect.TypeOf(P4{}), reflect.TypeOf(Particle{}), reflect.TypeOf(Event{}), } { rdict.StreamerInfos.Add(rdict.StreamerOf( rdict.StreamerInfos, typ, )) } const ( fname = "../testdata/groot-event-ntuple-nosplit.root" nevts = 5 ) func() { f, err := groot.Create(fname) if err != nil { log.Fatalf("could not create ROOT file: %+v", err) } defer f.Close() var ( evt Event wvars = []rtree.WriteVar{ {Name: "evt", Value: &evt}, } ) tree, err := rtree.NewWriter(f, "mytree", wvars) if err != nil { log.Fatalf("could not create tree writer: %+v", err) } defer tree.Close() fmt.Printf("-- created tree %q:\n", tree.Name()) for i, b := range tree.Branches() { fmt.Printf("branch[%d]: name=%q, title=%q\n", i, b.Name(), b.Title()) } for i := 0; i < nevts; i++ { evt.I32 = int32(i) evt.F64 = float64(i) evt.Str = fmt.Sprintf("evt-%0d", i) evt.Arr = [5]float64{float64(i), float64(i + 1), float64(i + 2), float64(i + 3), float64(i + 4)} evt.Sli = []float64{float64(i), float64(i + 1), float64(i + 2), float64(i + 3), float64(i + 4)}[:i] evt.P4 = P4{Px: float64(i), Py: float64(i + 1), Pz: float64(i + 2), E: float64(i + 3)} evt.Ps = []Particle{ {ID: int32(i), P4: evt.P4}, {ID: int32(i + 1), P4: evt.P4}, {ID: int32(i + 2), P4: evt.P4}, {ID: int32(i + 3), P4: evt.P4}, {ID: int32(i + 4), P4: evt.P4}, }[:i] _, err = tree.Write() if err != nil { log.Fatalf("could not write event %d: %+v", i, err) } } fmt.Printf("-- filled tree with %d entries\n", tree.Entries()) err = tree.Close() if err != nil { log.Fatalf("could not write tree: %+v", err) } err = f.Close() if err != nil { log.Fatalf("could not close tree: %+v", err) } }() { fmt.Printf("-- read back ROOT file\n") out := new(bytes.Buffer) err := rcmd.List(out, fname, rcmd.ListTrees(true)) if err != nil { log.Fatalf("could not list ROOT file content: %+v", err) } fmt.Printf("%s\n", out.String()) } { var ( deep = true filter = func(name string) bool { return true } ) out := new(bytes.Buffer) err := rcmd.Dump(out, fname, deep, filter) if err != nil { log.Fatalf("could not dump ROOT file: %+v", err) } fmt.Printf("%s\n", out.String()) } }
Output: -- created tree "mytree": branch[0]: name="evt", title="evt" -- filled tree with 5 entries -- read back ROOT file === [../testdata/groot-event-ntuple-nosplit.root] === version: 62202 TTree mytree (entries=5) evt "evt" TBranchElement key[000]: mytree;1 "" (TTree) [000][evt]: {0 0 evt-0 [0 1 2 3 4] [] {0 1 2 3} []} [001][evt]: {1 1 evt-1 [1 2 3 4 5] [1] {1 2 3 4} [{1 {1 2 3 4}}]} [002][evt]: {2 2 evt-2 [2 3 4 5 6] [2 3] {2 3 4 5} [{2 {2 3 4 5}} {3 {2 3 4 5}}]} [003][evt]: {3 3 evt-3 [3 4 5 6 7] [3 4 5] {3 4 5 6} [{3 {3 4 5 6}} {4 {3 4 5 6}} {5 {3 4 5 6}}]} [004][evt]: {4 4 evt-4 [4 5 6 7 8] [4 5 6 7] {4 5 6 7} [{4 {4 5 6 7}} {5 {4 5 6 7}} {6 {4 5 6 7}} {7 {4 5 6 7}}]}
Example (CreateFlatNtuple) ¶
package main import ( "fmt" "log" "go-hep.org/x/hep/groot" "go-hep.org/x/hep/groot/rtree" ) func main() { type Data struct { I32 int32 F64 float64 Str string ArrF64 [5]float64 N int32 SliF64 []float64 } const ( fname = "../testdata/groot-flat-ntuple.root" nevts = 5 ) func() { f, err := groot.Create(fname) if err != nil { log.Fatalf("%+v", err) } defer f.Close() var evt Data wvars := []rtree.WriteVar{ {Name: "I32", Value: &evt.I32}, {Name: "F64", Value: &evt.F64}, {Name: "Str", Value: &evt.Str}, {Name: "ArrF64", Value: &evt.ArrF64}, {Name: "N", Value: &evt.N}, {Name: "SliF64", Value: &evt.SliF64, Count: "N"}, } tree, err := rtree.NewWriter(f, "mytree", wvars) if err != nil { log.Fatalf("could not create tree writer: %+v", err) } defer tree.Close() fmt.Printf("-- created tree %q:\n", tree.Name()) for i, b := range tree.Branches() { fmt.Printf("branch[%d]: name=%q, title=%q\n", i, b.Name(), b.Title()) } for i := 0; i < nevts; i++ { evt.I32 = int32(i) evt.F64 = float64(i) evt.Str = fmt.Sprintf("evt-%0d", i) evt.ArrF64 = [5]float64{float64(i), float64(i + 1), float64(i + 2), float64(i + 3), float64(i + 4)} evt.N = int32(i) evt.SliF64 = []float64{float64(i), float64(i + 1), float64(i + 2), float64(i + 3), float64(i + 4)}[:i] _, err = tree.Write() if err != nil { log.Fatalf("could not write event %d: %+v", i, err) } } fmt.Printf("-- filled tree with %d entries\n", tree.Entries()) err = tree.Close() if err != nil { log.Fatalf("could not write tree: %+v", err) } err = f.Close() if err != nil { log.Fatalf("could not close tree: %+v", err) } }() func() { fmt.Printf("-- read back ROOT file\n") f, err := groot.Open(fname) if err != nil { log.Fatalf("could not open ROOT file: %+v", err) } defer f.Close() obj, err := f.Get("mytree") if err != nil { log.Fatalf("%+v", err) } tree := obj.(rtree.Tree) var data Data r, err := rtree.NewReader(tree, rtree.ReadVarsFromStruct(&data)) if err != nil { log.Fatal(err) } defer r.Close() err = r.Read(func(ctx rtree.RCtx) error { fmt.Printf("entry[%d]: %+v\n", ctx.Entry, data) return nil }) if err != nil { log.Fatal(err) } }() }
Output: -- created tree "mytree": branch[0]: name="I32", title="I32/I" branch[1]: name="F64", title="F64/D" branch[2]: name="Str", title="Str/C" branch[3]: name="ArrF64", title="ArrF64[5]/D" branch[4]: name="N", title="N/I" branch[5]: name="SliF64", title="SliF64[N]/D" -- filled tree with 5 entries -- read back ROOT file entry[0]: {I32:0 F64:0 Str:evt-0 ArrF64:[0 1 2 3 4] N:0 SliF64:[]} entry[1]: {I32:1 F64:1 Str:evt-1 ArrF64:[1 2 3 4 5] N:1 SliF64:[1]} entry[2]: {I32:2 F64:2 Str:evt-2 ArrF64:[2 3 4 5 6] N:2 SliF64:[2 3]} entry[3]: {I32:3 F64:3 Str:evt-3 ArrF64:[3 4 5 6 7] N:3 SliF64:[3 4 5]} entry[4]: {I32:4 F64:4 Str:evt-4 ArrF64:[4 5 6 7 8] N:4 SliF64:[4 5 6 7]}
Example (CreateFlatNtupleFromStruct) ¶
package main import ( "fmt" "log" "go-hep.org/x/hep/groot" "go-hep.org/x/hep/groot/rtree" ) func main() { type Data struct { I32 int32 F64 float64 Str string ArrF64 [5]float64 N int32 SliF64 []float64 `groot:"SliF64[N]"` } const ( fname = "../testdata/groot-flat-ntuple-with-struct.root" nevts = 5 ) func() { f, err := groot.Create(fname) if err != nil { log.Fatalf("%+v", err) } defer f.Close() var evt Data tree, err := rtree.NewWriter(f, "mytree", rtree.WriteVarsFromStruct(&evt)) if err != nil { log.Fatalf("could not create tree writer: %+v", err) } defer tree.Close() fmt.Printf("-- created tree %q:\n", tree.Name()) for i, b := range tree.Branches() { fmt.Printf("branch[%d]: name=%q, title=%q\n", i, b.Name(), b.Title()) } for i := 0; i < nevts; i++ { evt.I32 = int32(i) evt.F64 = float64(i) evt.Str = fmt.Sprintf("evt-%0d", i) evt.ArrF64 = [5]float64{float64(i), float64(i + 1), float64(i + 2), float64(i + 3), float64(i + 4)} evt.N = int32(i) evt.SliF64 = []float64{float64(i), float64(i + 1), float64(i + 2), float64(i + 3), float64(i + 4)}[:i] _, err = tree.Write() if err != nil { log.Fatalf("could not write event %d: %+v", i, err) } } fmt.Printf("-- filled tree with %d entries\n", tree.Entries()) err = tree.Close() if err != nil { log.Fatalf("could not write tree: %+v", err) } err = f.Close() if err != nil { log.Fatalf("could not close tree: %+v", err) } }() func() { fmt.Printf("-- read back ROOT file\n") f, err := groot.Open(fname) if err != nil { log.Fatalf("could not open ROOT file: %+v", err) } defer f.Close() obj, err := f.Get("mytree") if err != nil { log.Fatalf("%+v", err) } tree := obj.(rtree.Tree) var data Data r, err := rtree.NewReader(tree, rtree.ReadVarsFromStruct(&data)) if err != nil { log.Fatal(err) } defer r.Close() err = r.Read(func(ctx rtree.RCtx) error { fmt.Printf("entry[%d]: %+v\n", ctx.Entry, data) return nil }) if err != nil { log.Fatal(err) } }() }
Output: -- created tree "mytree": branch[0]: name="I32", title="I32/I" branch[1]: name="F64", title="F64/D" branch[2]: name="Str", title="Str/C" branch[3]: name="ArrF64", title="ArrF64[5]/D" branch[4]: name="N", title="N/I" branch[5]: name="SliF64", title="SliF64[N]/D" -- filled tree with 5 entries -- read back ROOT file entry[0]: {I32:0 F64:0 Str:evt-0 ArrF64:[0 1 2 3 4] N:0 SliF64:[]} entry[1]: {I32:1 F64:1 Str:evt-1 ArrF64:[1 2 3 4 5] N:1 SliF64:[1]} entry[2]: {I32:2 F64:2 Str:evt-2 ArrF64:[2 3 4 5 6] N:2 SliF64:[2 3]} entry[3]: {I32:3 F64:3 Str:evt-3 ArrF64:[3 4 5 6 7] N:3 SliF64:[3 4 5]} entry[4]: {I32:4 F64:4 Str:evt-4 ArrF64:[4 5 6 7 8] N:4 SliF64:[4 5 6 7]}
Example (CreateFlatNtupleWithLZMA) ¶
package main import ( "compress/flate" "fmt" "log" "go-hep.org/x/hep/groot" "go-hep.org/x/hep/groot/rtree" ) func main() { type Data struct { I32 int32 F64 float64 Str string ArrF64 [5]float64 N int32 SliF64 []float64 } const ( fname = "../testdata/groot-flat-ntuple-with-lzma.root" nevts = 5 ) func() { f, err := groot.Create(fname) if err != nil { log.Fatalf("%+v", err) } defer f.Close() var evt Data wvars := []rtree.WriteVar{ {Name: "I32", Value: &evt.I32}, {Name: "F64", Value: &evt.F64}, {Name: "Str", Value: &evt.Str}, {Name: "ArrF64", Value: &evt.ArrF64}, {Name: "N", Value: &evt.N}, {Name: "SliF64", Value: &evt.SliF64, Count: "N"}, } tree, err := rtree.NewWriter(f, "mytree", wvars, rtree.WithLZMA(flate.BestCompression), rtree.WithBasketSize(32*1024)) if err != nil { log.Fatalf("could not create tree writer: %+v", err) } defer tree.Close() fmt.Printf("-- created tree %q:\n", tree.Name()) for i, b := range tree.Branches() { fmt.Printf("branch[%d]: name=%q, title=%q\n", i, b.Name(), b.Title()) } for i := 0; i < nevts; i++ { evt.I32 = int32(i) evt.F64 = float64(i) evt.Str = fmt.Sprintf("evt-%0d", i) evt.ArrF64 = [5]float64{float64(i), float64(i + 1), float64(i + 2), float64(i + 3), float64(i + 4)} evt.N = int32(i) evt.SliF64 = []float64{float64(i), float64(i + 1), float64(i + 2), float64(i + 3), float64(i + 4)}[:i] _, err = tree.Write() if err != nil { log.Fatalf("could not write event %d: %+v", i, err) } } fmt.Printf("-- filled tree with %d entries\n", tree.Entries()) err = tree.Close() if err != nil { log.Fatalf("could not write tree: %+v", err) } err = f.Close() if err != nil { log.Fatalf("could not close tree: %+v", err) } }() func() { fmt.Printf("-- read back ROOT file\n") f, err := groot.Open(fname) if err != nil { log.Fatalf("could not open ROOT file: %+v", err) } defer f.Close() obj, err := f.Get("mytree") if err != nil { log.Fatalf("%+v", err) } tree := obj.(rtree.Tree) var data Data r, err := rtree.NewReader(tree, rtree.ReadVarsFromStruct(&data)) if err != nil { log.Fatal(err) } defer r.Close() err = r.Read(func(ctx rtree.RCtx) error { fmt.Printf("entry[%d]: %+v\n", ctx.Entry, data) return nil }) if err != nil { log.Fatal(err) } }() }
Output: -- created tree "mytree": branch[0]: name="I32", title="I32/I" branch[1]: name="F64", title="F64/D" branch[2]: name="Str", title="Str/C" branch[3]: name="ArrF64", title="ArrF64[5]/D" branch[4]: name="N", title="N/I" branch[5]: name="SliF64", title="SliF64[N]/D" -- filled tree with 5 entries -- read back ROOT file entry[0]: {I32:0 F64:0 Str:evt-0 ArrF64:[0 1 2 3 4] N:0 SliF64:[]} entry[1]: {I32:1 F64:1 Str:evt-1 ArrF64:[1 2 3 4 5] N:1 SliF64:[1]} entry[2]: {I32:2 F64:2 Str:evt-2 ArrF64:[2 3 4 5 6] N:2 SliF64:[2 3]} entry[3]: {I32:3 F64:3 Str:evt-3 ArrF64:[3 4 5 6 7] N:3 SliF64:[3 4 5]} entry[4]: {I32:4 F64:4 Str:evt-4 ArrF64:[4 5 6 7 8] N:4 SliF64:[4 5 6 7]}
Index ¶
- func Copy(dst Writer, src *Reader) (int64, error)
- func FileOf(tree Tree) *riofs.File
- type Basket
- type Branch
- type Leaf
- type LeafB
- func (leaf *LeafB) Branch() Branch
- func (leaf *LeafB) Class() string
- func (leaf *LeafB) HasRange() bool
- func (leaf *LeafB) IsUnsigned() bool
- func (leaf *LeafB) Kind() reflect.Kind
- func (leaf *LeafB) LeafCount() Leaf
- func (leaf *LeafB) Len() int
- func (leaf *LeafB) LenType() int
- func (leaf *LeafB) MarshalROOT(w *rbytes.WBuffer) (int, error)
- func (leaf *LeafB) Maximum() int8
- func (leaf *LeafB) Minimum() int8
- func (leaf *LeafB) Name() string
- func (leaf *LeafB) Offset() int
- func (*LeafB) RVersion() int16
- func (leaf *LeafB) Shape() []int
- func (leaf *LeafB) Title() string
- func (leaf *LeafB) Type() reflect.Type
- func (leaf *LeafB) TypeName() string
- func (leaf *LeafB) UnmarshalROOT(r *rbytes.RBuffer) error
- type LeafC
- func (leaf *LeafC) Branch() Branch
- func (leaf *LeafC) Class() string
- func (leaf *LeafC) HasRange() bool
- func (leaf *LeafC) IsUnsigned() bool
- func (leaf *LeafC) Kind() reflect.Kind
- func (leaf *LeafC) LeafCount() Leaf
- func (leaf *LeafC) Len() int
- func (leaf *LeafC) LenType() int
- func (leaf *LeafC) MarshalROOT(w *rbytes.WBuffer) (int, error)
- func (leaf *LeafC) Maximum() int32
- func (leaf *LeafC) Minimum() int32
- func (leaf *LeafC) Name() string
- func (leaf *LeafC) Offset() int
- func (*LeafC) RVersion() int16
- func (leaf *LeafC) Shape() []int
- func (leaf *LeafC) Title() string
- func (leaf *LeafC) Type() reflect.Type
- func (leaf *LeafC) TypeName() string
- func (leaf *LeafC) UnmarshalROOT(r *rbytes.RBuffer) error
- type LeafD
- func (leaf *LeafD) Branch() Branch
- func (leaf *LeafD) Class() string
- func (leaf *LeafD) HasRange() bool
- func (leaf *LeafD) IsUnsigned() bool
- func (leaf *LeafD) Kind() reflect.Kind
- func (leaf *LeafD) LeafCount() Leaf
- func (leaf *LeafD) Len() int
- func (leaf *LeafD) LenType() int
- func (leaf *LeafD) MarshalROOT(w *rbytes.WBuffer) (int, error)
- func (leaf *LeafD) Maximum() float64
- func (leaf *LeafD) Minimum() float64
- func (leaf *LeafD) Name() string
- func (leaf *LeafD) Offset() int
- func (*LeafD) RVersion() int16
- func (leaf *LeafD) Shape() []int
- func (leaf *LeafD) Title() string
- func (leaf *LeafD) Type() reflect.Type
- func (leaf *LeafD) TypeName() string
- func (leaf *LeafD) UnmarshalROOT(r *rbytes.RBuffer) error
- type LeafD32
- func (leaf *LeafD32) Branch() Branch
- func (leaf *LeafD32) Class() string
- func (leaf *LeafD32) HasRange() bool
- func (leaf *LeafD32) IsUnsigned() bool
- func (leaf *LeafD32) Kind() reflect.Kind
- func (leaf *LeafD32) LeafCount() Leaf
- func (leaf *LeafD32) Len() int
- func (leaf *LeafD32) LenType() int
- func (leaf *LeafD32) MarshalROOT(w *rbytes.WBuffer) (int, error)
- func (leaf *LeafD32) Maximum() root.Double32
- func (leaf *LeafD32) Minimum() root.Double32
- func (leaf *LeafD32) Name() string
- func (leaf *LeafD32) Offset() int
- func (*LeafD32) RVersion() int16
- func (leaf *LeafD32) Shape() []int
- func (leaf *LeafD32) Title() string
- func (leaf *LeafD32) Type() reflect.Type
- func (leaf *LeafD32) TypeName() string
- func (leaf *LeafD32) UnmarshalROOT(r *rbytes.RBuffer) error
- type LeafF
- func (leaf *LeafF) Branch() Branch
- func (leaf *LeafF) Class() string
- func (leaf *LeafF) HasRange() bool
- func (leaf *LeafF) IsUnsigned() bool
- func (leaf *LeafF) Kind() reflect.Kind
- func (leaf *LeafF) LeafCount() Leaf
- func (leaf *LeafF) Len() int
- func (leaf *LeafF) LenType() int
- func (leaf *LeafF) MarshalROOT(w *rbytes.WBuffer) (int, error)
- func (leaf *LeafF) Maximum() float32
- func (leaf *LeafF) Minimum() float32
- func (leaf *LeafF) Name() string
- func (leaf *LeafF) Offset() int
- func (*LeafF) RVersion() int16
- func (leaf *LeafF) Shape() []int
- func (leaf *LeafF) Title() string
- func (leaf *LeafF) Type() reflect.Type
- func (leaf *LeafF) TypeName() string
- func (leaf *LeafF) UnmarshalROOT(r *rbytes.RBuffer) error
- type LeafF16
- func (leaf *LeafF16) Branch() Branch
- func (leaf *LeafF16) Class() string
- func (leaf *LeafF16) HasRange() bool
- func (leaf *LeafF16) IsUnsigned() bool
- func (leaf *LeafF16) Kind() reflect.Kind
- func (leaf *LeafF16) LeafCount() Leaf
- func (leaf *LeafF16) Len() int
- func (leaf *LeafF16) LenType() int
- func (leaf *LeafF16) MarshalROOT(w *rbytes.WBuffer) (int, error)
- func (leaf *LeafF16) Maximum() root.Float16
- func (leaf *LeafF16) Minimum() root.Float16
- func (leaf *LeafF16) Name() string
- func (leaf *LeafF16) Offset() int
- func (*LeafF16) RVersion() int16
- func (leaf *LeafF16) Shape() []int
- func (leaf *LeafF16) Title() string
- func (leaf *LeafF16) Type() reflect.Type
- func (leaf *LeafF16) TypeName() string
- func (leaf *LeafF16) UnmarshalROOT(r *rbytes.RBuffer) error
- type LeafI
- func (leaf *LeafI) Branch() Branch
- func (leaf *LeafI) Class() string
- func (leaf *LeafI) HasRange() bool
- func (leaf *LeafI) IsUnsigned() bool
- func (leaf *LeafI) Kind() reflect.Kind
- func (leaf *LeafI) LeafCount() Leaf
- func (leaf *LeafI) Len() int
- func (leaf *LeafI) LenType() int
- func (leaf *LeafI) MarshalROOT(w *rbytes.WBuffer) (int, error)
- func (leaf *LeafI) Maximum() int32
- func (leaf *LeafI) Minimum() int32
- func (leaf *LeafI) Name() string
- func (leaf *LeafI) Offset() int
- func (*LeafI) RVersion() int16
- func (leaf *LeafI) Shape() []int
- func (leaf *LeafI) Title() string
- func (leaf *LeafI) Type() reflect.Type
- func (leaf *LeafI) TypeName() string
- func (leaf *LeafI) UnmarshalROOT(r *rbytes.RBuffer) error
- type LeafL
- func (leaf *LeafL) Branch() Branch
- func (leaf *LeafL) Class() string
- func (leaf *LeafL) HasRange() bool
- func (leaf *LeafL) IsUnsigned() bool
- func (leaf *LeafL) Kind() reflect.Kind
- func (leaf *LeafL) LeafCount() Leaf
- func (leaf *LeafL) Len() int
- func (leaf *LeafL) LenType() int
- func (leaf *LeafL) MarshalROOT(w *rbytes.WBuffer) (int, error)
- func (leaf *LeafL) Maximum() int64
- func (leaf *LeafL) Minimum() int64
- func (leaf *LeafL) Name() string
- func (leaf *LeafL) Offset() int
- func (*LeafL) RVersion() int16
- func (leaf *LeafL) Shape() []int
- func (leaf *LeafL) Title() string
- func (leaf *LeafL) Type() reflect.Type
- func (leaf *LeafL) TypeName() string
- func (leaf *LeafL) UnmarshalROOT(r *rbytes.RBuffer) error
- type LeafO
- func (leaf *LeafO) Branch() Branch
- func (leaf *LeafO) Class() string
- func (leaf *LeafO) HasRange() bool
- func (leaf *LeafO) IsUnsigned() bool
- func (leaf *LeafO) Kind() reflect.Kind
- func (leaf *LeafO) LeafCount() Leaf
- func (leaf *LeafO) Len() int
- func (leaf *LeafO) LenType() int
- func (leaf *LeafO) MarshalROOT(w *rbytes.WBuffer) (int, error)
- func (leaf *LeafO) Maximum() bool
- func (leaf *LeafO) Minimum() bool
- func (leaf *LeafO) Name() string
- func (leaf *LeafO) Offset() int
- func (*LeafO) RVersion() int16
- func (leaf *LeafO) Shape() []int
- func (leaf *LeafO) Title() string
- func (leaf *LeafO) Type() reflect.Type
- func (leaf *LeafO) TypeName() string
- func (leaf *LeafO) UnmarshalROOT(r *rbytes.RBuffer) error
- type LeafS
- func (leaf *LeafS) Branch() Branch
- func (leaf *LeafS) Class() string
- func (leaf *LeafS) HasRange() bool
- func (leaf *LeafS) IsUnsigned() bool
- func (leaf *LeafS) Kind() reflect.Kind
- func (leaf *LeafS) LeafCount() Leaf
- func (leaf *LeafS) Len() int
- func (leaf *LeafS) LenType() int
- func (leaf *LeafS) MarshalROOT(w *rbytes.WBuffer) (int, error)
- func (leaf *LeafS) Maximum() int16
- func (leaf *LeafS) Minimum() int16
- func (leaf *LeafS) Name() string
- func (leaf *LeafS) Offset() int
- func (*LeafS) RVersion() int16
- func (leaf *LeafS) Shape() []int
- func (leaf *LeafS) Title() string
- func (leaf *LeafS) Type() reflect.Type
- func (leaf *LeafS) TypeName() string
- func (leaf *LeafS) UnmarshalROOT(r *rbytes.RBuffer) error
- type RCtx
- type ReadOption
- type ReadVar
- type Reader
- type Tree
- type WriteOption
- type WriteVar
- type Writer
Examples ¶
- Package (CreateEventNtupleFullSplit)
- Package (CreateEventNtupleNoSplit)
- Package (CreateFlatNtuple)
- Package (CreateFlatNtupleFromStruct)
- Package (CreateFlatNtupleWithLZMA)
- Chain
- ChainOf
- Join
- Join (WithReadVarSelection)
- Reader
- Reader (WithChain)
- Reader (WithFormulaFromUser)
- Reader (WithFormulaFunc)
- Reader (WithRange)
- Reader (WithReadVarsFromStruct)
- Reader (WithReset)
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
Types ¶
type Basket ¶
type Basket struct {
// contains filtered or unexported fields
}
func (*Basket) MarshalROOT ¶ added in v0.20.0
type Branch ¶
type Branch interface { root.Named Branches() []Branch Leaves() []Leaf Branch(name string) Branch Leaf(name string) Leaf GoType() reflect.Type // contains filtered or unexported methods }
Branch describes a branch of a ROOT Tree.
type Leaf ¶
type Leaf interface { root.Named Branch() Branch HasRange() bool IsUnsigned() bool LeafCount() Leaf // returns the leaf count if is variable length Len() int // Len returns the number of fixed length elements LenType() int // LenType returns the number of bytes for this data type Shape() []int Offset() int Kind() reflect.Kind Type() reflect.Type TypeName() string // contains filtered or unexported methods }
Leaf describes branches data types
type LeafB ¶
type LeafB struct {
// contains filtered or unexported fields
}
LeafB implements ROOT TLeafB
func (*LeafB) IsUnsigned ¶
func (leaf *LeafB) IsUnsigned() bool
type LeafC ¶
type LeafC struct {
// contains filtered or unexported fields
}
LeafC implements ROOT TLeafC
func (*LeafC) IsUnsigned ¶
func (leaf *LeafC) IsUnsigned() bool
type LeafD ¶
type LeafD struct {
// contains filtered or unexported fields
}
LeafD implements ROOT TLeafD
func (*LeafD) IsUnsigned ¶
func (leaf *LeafD) IsUnsigned() bool
type LeafD32 ¶ added in v0.23.0
type LeafD32 struct {
// contains filtered or unexported fields
}
LeafD32 implements ROOT TLeafD32
func (*LeafD32) IsUnsigned ¶ added in v0.23.0
func (leaf *LeafD32) IsUnsigned() bool
func (*LeafD32) MarshalROOT ¶ added in v0.23.0
func (*LeafD32) Name ¶ added in v0.23.0
func (leaf *LeafD32) Name() string
Name returns the name of the instance
func (*LeafD32) Title ¶ added in v0.23.0
func (leaf *LeafD32) Title() string
Title returns the title of the instance
type LeafF ¶
type LeafF struct {
// contains filtered or unexported fields
}
LeafF implements ROOT TLeafF
func (*LeafF) IsUnsigned ¶
func (leaf *LeafF) IsUnsigned() bool
type LeafF16 ¶ added in v0.23.0
type LeafF16 struct {
// contains filtered or unexported fields
}
LeafF16 implements ROOT TLeafF16
func (*LeafF16) IsUnsigned ¶ added in v0.23.0
func (leaf *LeafF16) IsUnsigned() bool
func (*LeafF16) MarshalROOT ¶ added in v0.23.0
func (*LeafF16) Name ¶ added in v0.23.0
func (leaf *LeafF16) Name() string
Name returns the name of the instance
func (*LeafF16) Title ¶ added in v0.23.0
func (leaf *LeafF16) Title() string
Title returns the title of the instance
type LeafI ¶
type LeafI struct {
// contains filtered or unexported fields
}
LeafI implements ROOT TLeafI
func (*LeafI) IsUnsigned ¶
func (leaf *LeafI) IsUnsigned() bool
type LeafL ¶
type LeafL struct {
// contains filtered or unexported fields
}
LeafL implements ROOT TLeafL
func (*LeafL) IsUnsigned ¶
func (leaf *LeafL) IsUnsigned() bool
type LeafO ¶
type LeafO struct {
// contains filtered or unexported fields
}
LeafO implements ROOT TLeafO
func (*LeafO) IsUnsigned ¶
func (leaf *LeafO) IsUnsigned() bool
type LeafS ¶
type LeafS struct {
// contains filtered or unexported fields
}
LeafS implements ROOT TLeafS
func (*LeafS) IsUnsigned ¶
func (leaf *LeafS) IsUnsigned() bool
type RCtx ¶ added in v0.25.0
type RCtx struct {
Entry int64 // Current tree entry.
}
RCtx provides an entry-wise local context to the tree Reader.
type ReadOption ¶ added in v0.25.0
ReadOption configures how a ROOT tree should be traversed.
func WithPrefetchBaskets ¶ added in v0.27.0
func WithPrefetchBaskets(n int) ReadOption
WithPrefetchBaskets specifies the number of baskets to read-ahead, per branch. The default is 2. The number of prefetch baskets is cap'ed by the number of baskets, per branch.
func WithRange ¶ added in v0.25.0
func WithRange(beg, end int64) ReadOption
WithRange specifies the half-open interval [beg, end) of entries a Tree reader will read through.
type ReadVar ¶ added in v0.25.0
type ReadVar struct { Name string // name of the branch to read Leaf string // name of the leaf to read Value interface{} // pointer to the value to fill // contains filtered or unexported fields }
ReadVar describes a variable to be read out of a tree.
func NewReadVars ¶ added in v0.25.0
NewReadVars returns the complete set of ReadVars to read all the data contained in the provided Tree.
func ReadVarsFromStruct ¶ added in v0.26.0
func ReadVarsFromStruct(ptr interface{}) []ReadVar
ReadVarsFromStruct returns a list of ReadVars bound to the exported fields of the provided pointer to a struct value.
ReadVarsFromStruct panicks if the provided value is not a pointer to a struct value.
type Reader ¶ added in v0.25.0
type Reader struct {
// contains filtered or unexported fields
}
Reader reads data from a Tree.
Example ¶
package main import ( "fmt" "log" "go-hep.org/x/hep/groot" "go-hep.org/x/hep/groot/rtree" ) func main() { f, err := groot.Open("../testdata/simple.root") if err != nil { log.Fatalf("could not open ROOT file: %+v", err) } defer f.Close() o, err := f.Get("tree") if err != nil { log.Fatalf("could not retrieve ROOT tree: %+v", err) } t := o.(rtree.Tree) var ( v1 int32 v2 float32 v3 string rvars = []rtree.ReadVar{ {Name: "one", Value: &v1}, {Name: "two", Value: &v2}, {Name: "three", Value: &v3}, } ) r, err := rtree.NewReader(t, rvars) if err != nil { log.Fatalf("could not create tree reader: %+v", err) } defer r.Close() err = r.Read(func(ctx rtree.RCtx) error { fmt.Printf("evt[%d]: %v, %v, %v\n", ctx.Entry, v1, v2, v3) return nil }) if err != nil { log.Fatalf("could not process tree: %+v", err) } }
Output: evt[0]: 1, 1.1, uno evt[1]: 2, 2.2, dos evt[2]: 3, 3.3, tres evt[3]: 4, 4.4, quatro
Example (WithChain) ¶
package main import ( "fmt" "log" "go-hep.org/x/hep/groot" "go-hep.org/x/hep/groot/rtree" ) func main() { f, err := groot.Open("../testdata/simple.root") if err != nil { log.Fatalf("could not open ROOT file: %+v", err) } defer f.Close() o, err := f.Get("tree") if err != nil { log.Fatalf("could not retrieve ROOT tree: %+v", err) } t := o.(rtree.Tree) t = rtree.Chain(t, t, t, t) var ( v1 int32 v2 float32 v3 string rvars = []rtree.ReadVar{ {Name: "one", Value: &v1}, {Name: "two", Value: &v2}, {Name: "three", Value: &v3}, } ) r, err := rtree.NewReader(t, rvars, rtree.WithRange(0, -1), rtree.WithPrefetchBaskets(2), ) if err != nil { log.Fatalf("could not create tree reader: %+v", err) } defer r.Close() err = r.Read(func(ctx rtree.RCtx) error { fmt.Printf("evt[%d]: %v, %v, %v\n", ctx.Entry, v1, v2, v3) return nil }) if err != nil { log.Fatalf("could not process tree: %+v", err) } }
Output: evt[0]: 1, 1.1, uno evt[1]: 2, 2.2, dos evt[2]: 3, 3.3, tres evt[3]: 4, 4.4, quatro evt[4]: 1, 1.1, uno evt[5]: 2, 2.2, dos evt[6]: 3, 3.3, tres evt[7]: 4, 4.4, quatro evt[8]: 1, 1.1, uno evt[9]: 2, 2.2, dos evt[10]: 3, 3.3, tres evt[11]: 4, 4.4, quatro evt[12]: 1, 1.1, uno evt[13]: 2, 2.2, dos evt[14]: 3, 3.3, tres evt[15]: 4, 4.4, quatro
Example (WithFormulaFromUser) ¶
package main import ( "fmt" "log" "go-hep.org/x/hep/groot" "go-hep.org/x/hep/groot/rtree" ) type UsrF64 struct { rvars []string v1 *int32 v2 *float32 v3 *string fct func(int32, float32, string) float64 } func (usr *UsrF64) RVars() []string { return usr.rvars } func (usr *UsrF64) Bind(args []interface{}) error { if got, want := len(args), 3; got != want { return fmt.Errorf( "rfunc: invalid number of bind arguments (got=%d, want=%d)", got, want, ) } usr.v1 = args[0].(*int32) usr.v2 = args[1].(*float32) usr.v3 = args[2].(*string) return nil } func (usr *UsrF64) Func() interface{} { return func() float64 { return usr.fct(*usr.v1, *usr.v2, *usr.v3) } } type UsrStr struct { rvars []string v1 *int32 v2 *float32 v3 *string fct func(int32, float32, string) string } func (usr *UsrStr) RVars() []string { return usr.rvars } func (usr *UsrStr) Bind(args []interface{}) error { if got, want := len(args), 3; got != want { return fmt.Errorf( "rfunc: invalid number of bind arguments (got=%d, want=%d)", got, want, ) } usr.v1 = args[0].(*int32) usr.v2 = args[1].(*float32) usr.v3 = args[2].(*string) return nil } func (usr *UsrStr) Func() interface{} { return func() string { return usr.fct(*usr.v1, *usr.v2, *usr.v3) } } func main() { f, err := groot.Open("../testdata/simple.root") if err != nil { log.Fatalf("could not open ROOT file: %+v", err) } defer f.Close() o, err := f.Get("tree") if err != nil { log.Fatalf("could not retrieve ROOT tree: %+v", err) } t := o.(rtree.Tree) var ( data struct { V1 int32 `groot:"one"` V2 float32 `groot:"two"` V3 string `groot:"three"` } rvars = rtree.ReadVarsFromStruct(&data) ) r, err := rtree.NewReader(t, rvars) if err != nil { log.Fatalf("could not create tree reader: %+v", err) } defer r.Close() f64, err := r.Formula(&UsrF64{ rvars: []string{"one", "two", "three"}, fct: func(v1 int32, v2 float32, v3 string) float64 { return float64(v2*10) + float64(1000*v1) + float64(100*len(v3)) }, }) if err != nil { log.Fatalf("could not create formula: %+v", err) } fstr, err := r.Formula(&UsrStr{ rvars: []string{"one", "two", "three"}, fct: func(v1 int32, v2 float32, v3 string) string { return fmt.Sprintf( "%q: %v, %q: %v, %q: %v", "one", v1, "two", v2, "three", v3, ) }, }) if err != nil { log.Fatalf("could not create formula: %+v", err) } f1 := f64.Func().(func() float64) f2 := fstr.Func().(func() string) err = r.Read(func(ctx rtree.RCtx) error { v64 := f1() str := f2() fmt.Printf("evt[%d]: %v, %v, %v -> %g | %s\n", ctx.Entry, data.V1, data.V2, data.V3, v64, str) return nil }) if err != nil { log.Fatalf("could not process tree: %+v", err) } }
Output: evt[0]: 1, 1.1, uno -> 1311 | "one": 1, "two": 1.1, "three": uno evt[1]: 2, 2.2, dos -> 2322 | "one": 2, "two": 2.2, "three": dos evt[2]: 3, 3.3, tres -> 3433 | "one": 3, "two": 3.3, "three": tres evt[3]: 4, 4.4, quatro -> 4644 | "one": 4, "two": 4.4, "three": quatro
Example (WithFormulaFunc) ¶
package main import ( "fmt" "log" "go-hep.org/x/hep/groot" "go-hep.org/x/hep/groot/rtree" ) func main() { f, err := groot.Open("../testdata/simple.root") if err != nil { log.Fatalf("could not open ROOT file: %+v", err) } defer f.Close() o, err := f.Get("tree") if err != nil { log.Fatalf("could not retrieve ROOT tree: %+v", err) } t := o.(rtree.Tree) var ( data struct { V1 int32 `groot:"one"` V2 float32 `groot:"two"` V3 string `groot:"three"` } rvars = rtree.ReadVarsFromStruct(&data) ) r, err := rtree.NewReader(t, rvars) if err != nil { log.Fatalf("could not create tree reader: %+v", err) } defer r.Close() f64, err := r.FormulaFunc( []string{"one", "two", "three"}, func(v1 int32, v2 float32, v3 string) float64 { return float64(v2*10) + float64(1000*v1) + float64(100*len(v3)) }, ) if err != nil { log.Fatalf("could not create formula: %+v", err) } fstr, err := r.FormulaFunc( []string{"one", "two", "three"}, func(v1 int32, v2 float32, v3 string) string { return fmt.Sprintf( "%q: %v, %q: %v, %q: %v", "one", v1, "two", v2, "three", v3, ) }, ) if err != nil { log.Fatalf("could not create formula: %+v", err) } f1 := f64.Func().(func() float64) f2 := fstr.Func().(func() string) err = r.Read(func(ctx rtree.RCtx) error { v64 := f1() str := f2() fmt.Printf("evt[%d]: %v, %v, %v -> %g | %s\n", ctx.Entry, data.V1, data.V2, data.V3, v64, str) return nil }) if err != nil { log.Fatalf("could not process tree: %+v", err) } }
Output: evt[0]: 1, 1.1, uno -> 1311 | "one": 1, "two": 1.1, "three": uno evt[1]: 2, 2.2, dos -> 2322 | "one": 2, "two": 2.2, "three": dos evt[2]: 3, 3.3, tres -> 3433 | "one": 3, "two": 3.3, "three": tres evt[3]: 4, 4.4, quatro -> 4644 | "one": 4, "two": 4.4, "three": quatro
Example (WithRange) ¶
package main import ( "fmt" "log" "go-hep.org/x/hep/groot" "go-hep.org/x/hep/groot/rtree" ) func main() { f, err := groot.Open("../testdata/simple.root") if err != nil { log.Fatalf("could not open ROOT file: %+v", err) } defer f.Close() o, err := f.Get("tree") if err != nil { log.Fatalf("could not retrieve ROOT tree: %+v", err) } t := o.(rtree.Tree) var ( v1 int32 v2 float32 v3 string rvars = []rtree.ReadVar{ {Name: "one", Value: &v1}, {Name: "two", Value: &v2}, {Name: "three", Value: &v3}, } ) r, err := rtree.NewReader(t, rvars, rtree.WithRange(1, 3)) if err != nil { log.Fatalf("could not create tree reader: %+v", err) } defer r.Close() err = r.Read(func(ctx rtree.RCtx) error { fmt.Printf("evt[%d]: %v, %v, %v\n", ctx.Entry, v1, v2, v3) return nil }) if err != nil { log.Fatalf("could not process tree: %+v", err) } }
Output: evt[1]: 2, 2.2, dos evt[2]: 3, 3.3, tres
Example (WithReadVarsFromStruct) ¶
package main import ( "fmt" "log" "go-hep.org/x/hep/groot" "go-hep.org/x/hep/groot/rtree" ) func main() { f, err := groot.Open("../testdata/simple.root") if err != nil { log.Fatalf("could not open ROOT file: %+v", err) } defer f.Close() o, err := f.Get("tree") if err != nil { log.Fatalf("could not retrieve ROOT tree: %+v", err) } t := o.(rtree.Tree) var ( data struct { V1 int32 `groot:"one"` V2 float32 `groot:"two"` V3 string `groot:"three"` } rvars = rtree.ReadVarsFromStruct(&data) ) r, err := rtree.NewReader(t, rvars) if err != nil { log.Fatalf("could not create tree reader: %+v", err) } defer r.Close() err = r.Read(func(ctx rtree.RCtx) error { fmt.Printf("evt[%d]: %v, %v, %v\n", ctx.Entry, data.V1, data.V2, data.V3) return nil }) if err != nil { log.Fatalf("could not process tree: %+v", err) } }
Output: evt[0]: 1, 1.1, uno evt[1]: 2, 2.2, dos evt[2]: 3, 3.3, tres evt[3]: 4, 4.4, quatro
Example (WithReset) ¶
package main import ( "fmt" "log" "go-hep.org/x/hep/groot" "go-hep.org/x/hep/groot/rtree" ) func main() { f, err := groot.Open("../testdata/simple.root") if err != nil { log.Fatalf("could not open ROOT file: %+v", err) } defer f.Close() o, err := f.Get("tree") if err != nil { log.Fatalf("could not retrieve ROOT tree: %+v", err) } t := o.(rtree.Tree) var ( v1 int32 v2 float32 v3 string rvars = []rtree.ReadVar{ {Name: "one", Value: &v1}, {Name: "two", Value: &v2}, {Name: "three", Value: &v3}, } ) r, err := rtree.NewReader(t, rvars) if err != nil { log.Fatalf("could not create tree reader: %+v", err) } defer r.Close() err = r.Reset() if err != nil { log.Fatalf("could not reset tree reader: %+v", err) } err = r.Reset(rtree.WithRange(1, 3)) if err != nil { log.Fatalf("could not reset tree reader: %+v", err) } err = r.Read(func(ctx rtree.RCtx) error { fmt.Printf("evt[%d]: %v, %v, %v\n", ctx.Entry, v1, v2, v3) return nil }) if err != nil { log.Fatalf("could not process tree: %+v", err) } }
Output: evt[1]: 2, 2.2, dos evt[2]: 3, 3.3, tres
func NewReader ¶ added in v0.25.0
func NewReader(t Tree, rvars []ReadVar, opts ...ReadOption) (*Reader, error)
NewReader creates a new Tree Reader from the provided ROOT Tree and the set of read-variables into which data will be read.
func (*Reader) Formula ¶ added in v0.26.0
Formula creates a new formula based on the provided user provided formula. Formula binds the provided function with the requested list of leaves.
func (*Reader) FormulaFunc ¶ added in v0.27.0
FormulaFunc creates a new formula based on the provided function and the list of branches as inputs.
func (*Reader) Read ¶ added in v0.25.0
Read will read data from the underlying tree over the whole specified range. Read calls the provided user function f for each entry successfully read.
func (*Reader) Reset ¶ added in v0.28.0
func (r *Reader) Reset(opts ...ReadOption) error
Reset resets the current Reader with the provided options.
type Tree ¶
type Tree interface { root.Named Entries() int64 Branch(name string) Branch Branches() []Branch Leaf(name string) Leaf Leaves() []Leaf }
func Chain ¶
Chain returns a Tree that is the concatenation of all the input Trees.
Example ¶
ExampleChain shows how to create a chain made of 2 trees.
package main import ( "fmt" "log" "go-hep.org/x/hep/groot" "go-hep.org/x/hep/groot/rtree" ) func main() { const name = "tree" f1, err := groot.Open("../testdata/chain.1.root") if err != nil { log.Fatal(err) } defer f1.Close() o1, err := f1.Get(name) if err != nil { log.Fatal(err) } t1 := o1.(rtree.Tree) f2, err := groot.Open("../testdata/chain.2.root") if err != nil { log.Fatal(err) } defer f2.Close() o2, err := f2.Get(name) if err != nil { log.Fatal(err) } t2 := o2.(rtree.Tree) chain := rtree.Chain(t1, t2) type Data struct { Event struct { Beg string `groot:"Beg"` F64 float64 `groot:"F64"` ArrF64 [10]float64 `groot:"ArrayF64"` N int32 `groot:"N"` SliF64 []float64 `groot:"SliceF64"` StdStr string `groot:"StdStr"` StlVecF64 []float64 `groot:"StlVecF64"` StlVecStr []string `groot:"StlVecStr"` End string `groot:"End"` } `groot:"evt"` } var data Data r, err := rtree.NewReader(chain, rtree.ReadVarsFromStruct(&data)) if err != nil { log.Fatal(err) } defer r.Close() err = r.Read(func(ctx rtree.RCtx) error { fmt.Printf( "entry[%02d]: beg=%q f64=%v\n", ctx.Entry, data.Event.Beg, data.Event.F64, ) return nil }) if err != nil { log.Fatalf("error during scan: %v", err) } }
Output: entry[00]: beg="beg-000" f64=0 entry[01]: beg="beg-001" f64=1 entry[02]: beg="beg-002" f64=2 entry[03]: beg="beg-003" f64=3 entry[04]: beg="beg-004" f64=4 entry[05]: beg="beg-005" f64=5 entry[06]: beg="beg-006" f64=6 entry[07]: beg="beg-007" f64=7 entry[08]: beg="beg-008" f64=8 entry[09]: beg="beg-009" f64=9 entry[10]: beg="beg-010" f64=10 entry[11]: beg="beg-011" f64=11 entry[12]: beg="beg-012" f64=12 entry[13]: beg="beg-013" f64=13 entry[14]: beg="beg-014" f64=14 entry[15]: beg="beg-015" f64=15 entry[16]: beg="beg-016" f64=16 entry[17]: beg="beg-017" f64=17 entry[18]: beg="beg-018" f64=18 entry[19]: beg="beg-019" f64=19
func ChainOf ¶
ChainOf returns a Tree, a close function and an error if any. The tree is the logical concatenation of all the name trees located in the input named files. The close function allows to close all the open named files.
Example ¶
ExampleChainOf shows how to create a chain made of trees from 2 files.
package main import ( "fmt" "log" "go-hep.org/x/hep/groot/rtree" ) func main() { const name = "tree" chain, closer, err := rtree.ChainOf(name, "../testdata/chain.1.root", "../testdata/chain.2.root") if err != nil { log.Fatal(err) } defer func() { err = closer() if err != nil { log.Fatalf("could not close ROOT chain: %+v", err) } }() type Data struct { Event struct { Beg string `groot:"Beg"` F64 float64 `groot:"F64"` ArrF64 [10]float64 `groot:"ArrayF64"` N int32 `groot:"N"` SliF64 []float64 `groot:"SliceF64"` StdStr string `groot:"StdStr"` StlVecF64 []float64 `groot:"StlVecF64"` StlVecStr []string `groot:"StlVecStr"` End string `groot:"End"` } `groot:"evt"` } var data Data r, err := rtree.NewReader(chain, rtree.ReadVarsFromStruct(&data)) if err != nil { log.Fatal(err) } defer r.Close() err = r.Read(func(ctx rtree.RCtx) error { fmt.Printf( "entry[%02d]: beg=%q f64=%v\n", ctx.Entry, data.Event.Beg, data.Event.F64, ) return nil }) if err != nil { log.Fatalf("error during scan: %v", err) } }
Output: entry[00]: beg="beg-000" f64=0 entry[01]: beg="beg-001" f64=1 entry[02]: beg="beg-002" f64=2 entry[03]: beg="beg-003" f64=3 entry[04]: beg="beg-004" f64=4 entry[05]: beg="beg-005" f64=5 entry[06]: beg="beg-006" f64=6 entry[07]: beg="beg-007" f64=7 entry[08]: beg="beg-008" f64=8 entry[09]: beg="beg-009" f64=9 entry[10]: beg="beg-010" f64=10 entry[11]: beg="beg-011" f64=11 entry[12]: beg="beg-012" f64=12 entry[13]: beg="beg-013" f64=13 entry[14]: beg="beg-014" f64=14 entry[15]: beg="beg-015" f64=15 entry[16]: beg="beg-016" f64=16 entry[17]: beg="beg-017" f64=17 entry[18]: beg="beg-018" f64=18 entry[19]: beg="beg-019" f64=19
func Join ¶ added in v0.28.0
Join returns a new Tree that represents the logical join of the input trees. The returned tree will contain all the columns of all the input trees. Join errors out if the input slice of trees is empty. Join errors out if the input trees do not have the same amount of entries. Join errors out if two trees have each a column with the same name.
Example ¶
package main import ( "fmt" "log" "go-hep.org/x/hep/groot" "go-hep.org/x/hep/groot/rtree" ) func main() { get := func(fname, tname string) (rtree.Tree, func() error) { f, err := groot.Open(fname) if err != nil { log.Fatal(err) } t, err := f.Get(tname) if err != nil { _ = f.Close() log.Fatal(err) } return t.(rtree.Tree), f.Close } chk := func(f func() error) { err := f() if err != nil { log.Fatal(err) } } t1, f1 := get("../testdata/join1.root", "j1") defer chk(f1) t2, f2 := get("../testdata/join2.root", "j2") defer chk(f2) t3, f3 := get("../testdata/join3.root", "j3") defer chk(f3) join, err := rtree.Join(t1, t2, t3) if err != nil { log.Fatalf("could not join trees: %+v", err) } fmt.Printf("t1: %s (nevts=%d)\n", t1.Name(), t1.Entries()) fmt.Printf("t2: %s (nevts=%d)\n", t2.Name(), t2.Entries()) fmt.Printf("t3: %s (nevts=%d)\n", t3.Name(), t3.Entries()) fmt.Printf("join: %s\n", join.Name()) fmt.Printf("entries: %d\n", join.Entries()) rvars := rtree.NewReadVars(join) r, err := rtree.NewReader(join, rvars) if err != nil { log.Fatalf("could not create reader for joined trees: %+v", err) } defer r.Close() rf1, err := r.FormulaFunc( []string{"b10", "b30", "b20"}, func(b1, b3, b2 float64) float64 { return b1 + b2 + b3 }, ) if err != nil { log.Fatalf("could not bind formula: %+v", err) } fct1 := rf1.Func().(func() float64) err = r.Read(func(rctx rtree.RCtx) error { for _, rv := range rvars { fmt.Printf("join[%03d][%s]: %v\n", rctx.Entry, rv.Name, rv.Deref()) } fmt.Printf("join[%03d][fun]: %v\n", rctx.Entry, fct1()) return nil }) if err != nil { log.Fatalf("could not process events: %+v", err) } }
Output: t1: j1 (nevts=10) t2: j2 (nevts=10) t3: j3 (nevts=10) join: join_j1_j2_j3 entries: 10 join[000][b10]: 101 join[000][b11]: 101 join[000][b12]: j1-101 join[000][b20]: 201 join[000][b21]: 201 join[000][b22]: j2-201 join[000][b30]: 301 join[000][b31]: 301 join[000][b32]: j3-301 join[000][fun]: 603 join[001][b10]: 102 join[001][b11]: 102 join[001][b12]: j1-102 join[001][b20]: 202 join[001][b21]: 202 join[001][b22]: j2-202 join[001][b30]: 302 join[001][b31]: 302 join[001][b32]: j3-302 join[001][fun]: 606 join[002][b10]: 103 join[002][b11]: 103 join[002][b12]: j1-103 join[002][b20]: 203 join[002][b21]: 203 join[002][b22]: j2-203 join[002][b30]: 303 join[002][b31]: 303 join[002][b32]: j3-303 join[002][fun]: 609 join[003][b10]: 104 join[003][b11]: 104 join[003][b12]: j1-104 join[003][b20]: 204 join[003][b21]: 204 join[003][b22]: j2-204 join[003][b30]: 304 join[003][b31]: 304 join[003][b32]: j3-304 join[003][fun]: 612 join[004][b10]: 105 join[004][b11]: 105 join[004][b12]: j1-105 join[004][b20]: 205 join[004][b21]: 205 join[004][b22]: j2-205 join[004][b30]: 305 join[004][b31]: 305 join[004][b32]: j3-305 join[004][fun]: 615 join[005][b10]: 106 join[005][b11]: 106 join[005][b12]: j1-106 join[005][b20]: 206 join[005][b21]: 206 join[005][b22]: j2-206 join[005][b30]: 306 join[005][b31]: 306 join[005][b32]: j3-306 join[005][fun]: 618 join[006][b10]: 107 join[006][b11]: 107 join[006][b12]: j1-107 join[006][b20]: 207 join[006][b21]: 207 join[006][b22]: j2-207 join[006][b30]: 307 join[006][b31]: 307 join[006][b32]: j3-307 join[006][fun]: 621 join[007][b10]: 108 join[007][b11]: 108 join[007][b12]: j1-108 join[007][b20]: 208 join[007][b21]: 208 join[007][b22]: j2-208 join[007][b30]: 308 join[007][b31]: 308 join[007][b32]: j3-308 join[007][fun]: 624 join[008][b10]: 109 join[008][b11]: 109 join[008][b12]: j1-109 join[008][b20]: 209 join[008][b21]: 209 join[008][b22]: j2-209 join[008][b30]: 309 join[008][b31]: 309 join[008][b32]: j3-309 join[008][fun]: 627 join[009][b10]: 110 join[009][b11]: 110 join[009][b12]: j1-110 join[009][b20]: 210 join[009][b21]: 210 join[009][b22]: j2-210 join[009][b30]: 310 join[009][b31]: 310 join[009][b32]: j3-310 join[009][fun]: 630
Example (WithReadVarSelection) ¶
package main import ( "fmt" "log" "strings" "go-hep.org/x/hep/groot" "go-hep.org/x/hep/groot/rtree" ) func main() { get := func(fname, tname string) (rtree.Tree, func() error) { f, err := groot.Open(fname) if err != nil { log.Fatal(err) } t, err := f.Get(tname) if err != nil { _ = f.Close() log.Fatal(err) } return t.(rtree.Tree), f.Close } chk := func(f func() error) { err := f() if err != nil { log.Fatal(err) } } t1, f1 := get("../testdata/join1.root", "j1") defer chk(f1) t2, f2 := get("../testdata/join2.root", "j2") defer chk(f2) t3, f3 := get("../testdata/join3.root", "j3") defer chk(f3) join, err := rtree.Join(t1, t2, t3) if err != nil { log.Fatalf("could not join trees: %+v", err) } fmt.Printf("t1: %s (nevts=%d)\n", t1.Name(), t1.Entries()) fmt.Printf("t2: %s (nevts=%d)\n", t2.Name(), t2.Entries()) fmt.Printf("t3: %s (nevts=%d)\n", t3.Name(), t3.Entries()) fmt.Printf("join: %s\n", join.Name()) fmt.Printf("entries: %d\n", join.Entries()) rvars := []rtree.ReadVar{ {Name: "b10", Value: new(float64)}, {Name: "b20", Value: new(float64)}, } r, err := rtree.NewReader(join, rvars, rtree.WithRange(3, 8)) if err != nil { log.Fatalf("could not create reader for joined trees: %+v", err) } defer r.Close() rf1, err := r.FormulaFunc( []string{"b12", "b32", "b22"}, func(b1, b3, b2 string) string { return strings.Join([]string{b1, b3, b2}, ", ") }, ) if err != nil { log.Fatalf("could not bind formula: %+v", err) } fct1 := rf1.Func().(func() string) err = r.Read(func(rctx rtree.RCtx) error { for _, rv := range rvars { fmt.Printf("join[%03d][%s]: %v\n", rctx.Entry, rv.Name, rv.Deref()) } fmt.Printf("join[%03d][fun]: %v\n", rctx.Entry, fct1()) return nil }) if err != nil { log.Fatalf("could not process events: %+v", err) } }
Output: t1: j1 (nevts=10) t2: j2 (nevts=10) t3: j3 (nevts=10) join: join_j1_j2_j3 entries: 10 join[003][b10]: 104 join[003][b20]: 204 join[003][fun]: j1-104, j3-304, j2-204 join[004][b10]: 105 join[004][b20]: 205 join[004][fun]: j1-105, j3-305, j2-205 join[005][b10]: 106 join[005][b20]: 206 join[005][fun]: j1-106, j3-306, j2-206 join[006][b10]: 107 join[006][b20]: 207 join[006][fun]: j1-107, j3-307, j2-207 join[007][b10]: 108 join[007][b20]: 208 join[007][fun]: j1-108, j3-308, j2-208
type WriteOption ¶ added in v0.21.0
type WriteOption func(opt *wopt) error
WriteOption configures how a ROOT tree (and its branches) should be created.
func WithBasketSize ¶ added in v0.21.0
func WithBasketSize(size int) WriteOption
WithBasketSize configures a ROOT tree to use 'size' (in bytes) as a basket buffer size. if size is <= 0, the default buffer size is used (DefaultBasketSize).
func WithLZ4 ¶ added in v0.21.0
func WithLZ4(level int) WriteOption
WithLZ4 configures a ROOT tree to use LZ4 as a compression mechanism.
func WithLZMA ¶ added in v0.21.0
func WithLZMA(level int) WriteOption
WithLZMA configures a ROOT tree to use LZMA as a compression mechanism.
func WithSplitLevel ¶ added in v0.28.0
func WithSplitLevel(lvl int) WriteOption
WithSplitLevel sets the maximum branch depth split level
func WithTitle ¶ added in v0.22.0
func WithTitle(title string) WriteOption
WithTitle sets the title of the tree writer.
func WithZlib ¶ added in v0.21.0
func WithZlib(level int) WriteOption
WithZlib configures a ROOT tree to use zlib as a compression mechanism.
func WithoutCompression ¶ added in v0.21.0
func WithoutCompression() WriteOption
WithoutCompression configures a ROOT tree to not use any compression mechanism.
type WriteVar ¶ added in v0.20.0
type WriteVar struct { Name string // name of the variable Value interface{} // pointer to the value to write Count string // name of the branch holding the count-leaf value for slices }
WriteVar describes a variable to be written out to a tree.
func WriteVarsFromStruct ¶ added in v0.21.0
func WriteVarsFromStruct(ptr interface{}, opts ...WriteOption) []WriteVar
WriteVarsFromStruct creates a slice of WriteVars from the ptr value. WriteVarsFromStruct panics if ptr is not a pointer to a struct value. WriteVarsFromStruct ignores fields that are not exported.
func WriteVarsFromTree ¶ added in v0.22.0
WriteVarsFromTree creates a slice of WriteVars from the tree value.
type Writer ¶ added in v0.20.0
type Writer interface { Tree // Write writes the event data to ROOT storage and returns the number // of bytes (before compression, if any) written. Write() (int, error) // Flush commits the current contents of the tree to stable storage. Flush() error // Close writes metadata and closes the tree. Close() error }
Writer is the interface that wraps the Write method for Trees.