diff --git a/src/CoordVisualize.jl b/src/CoordVisualize.jl
index e848564..5726392 100644
--- a/src/CoordVisualize.jl
+++ b/src/CoordVisualize.jl
@@ -3,7 +3,9 @@ module CoordVisualize
 using Dates
 
 export CoordLog
-export interactive_edit_log
+export iedit_log
+export isplit_log!, iedit_note!, ijoin_logs!
+export export_log
 export ColorMapFuncs
 
 include("typedef.jl")
diff --git a/src/edit.jl b/src/edit.jl
index 3458d34..7a432dd 100644
--- a/src/edit.jl
+++ b/src/edit.jl
@@ -3,7 +3,12 @@
 
 Split `log` at `at`, i.e. to `1:at` and `(at + 1):end` then assign `notes_1` and `notes_2` to notes for each other.
 """
-function split_log(log::CoordLog, at::Unsigned, notes_1::AbstractString, notes_2::AbstractString)::Tuple{CoordLog, CoordLog}
+function split_log(
+    log::CoordLog,
+    at::Unsigned,
+    notes_1::AbstractString,
+    notes_2::AbstractString,
+)::Tuple{CoordLog, CoordLog}
     @assert at < size(log.coords)[1] "Split index must be less than original log length($(size(log.coords)[1]))"
     (
         CoordLog(log.coords[1:at, :], log.logdate, notes_1),
@@ -11,11 +16,15 @@ function split_log(log::CoordLog, at::Unsigned, notes_1::AbstractString, notes_2
     )
 end
 
-function split_log(log::CoordLog, at::Integer, notes_1::AbstractString, notes_2::AbstractString)::Tuple{CoordLog, CoordLog}
+function split_log(
+    log::CoordLog,
+    at::Integer,
+    notes_1::AbstractString,
+    notes_2::AbstractString,
+)::Tuple{CoordLog, CoordLog}
     split_log(log, UInt(at), notes_1, notes_2)
 end
 
-
 """
     assign_note!(log::CoordLog, new_note::AbstractString)
 
@@ -24,3 +33,21 @@ Replace `note` in `log` with `new_note`.
 function assign_note!(log::CoordLog, new_note::AbstractString)
     log.note = new_note
 end
+
+"""
+    join_log(
+        log1::CoordLog{T},
+        log2::CoordLog{T},
+        note::AbstractString,
+    )::CoordLog{T} where {T}
+
+Join two logs.
+"""
+function join_log(
+    log1::CoordLog{T},
+    log2::CoordLog{T},
+    note::AbstractString,
+)::CoordLog{T} where {T}
+    newdate = min(log1.logdate, log2.logdate)
+    CoordLog(vcat(log1.coords, log2.coords), newdate, note)
+end
diff --git a/src/interactive_edit.jl b/src/interactive_edit.jl
index 1277c44..298a8f8 100644
--- a/src/interactive_edit.jl
+++ b/src/interactive_edit.jl
@@ -2,7 +2,7 @@ using Statistics
 using Dates
 using Printf
 
-function interactive_edit_log(filenames...; writetofile = true)
+function iedit_log(filenames...; writetofile = true)
     printstyled(stdout, "[CoordLog Editor] \n", color = :blue, bold = true)
     logs = CoordLog[]
     printstyled(stdout, "loading log files\n", color = :blue)
@@ -10,7 +10,7 @@ function interactive_edit_log(filenames...; writetofile = true)
         append!(logs, parse_log(file))
     end
     printstyled(stdout, "all files loaded\n", color = :blue)
-    edited_logs = CoordLog[]
+    edited_logs = CoordLog{Float64}[]
     for (i, log) in enumerate(logs)
         printstyled(stdout, "LogEdit: editing log $(i) / $(length(logs))\n", color = :blue)
         printstyled(stdout, "summary\n", color = :cyan)
@@ -60,14 +60,16 @@ function interactive_edit_log(filenames...; writetofile = true)
                 note_1 = readline(stdin)
                 new_log, log = split_log(log, at, note_1, "")
                 push!(edited_logs, new_log)
-                print("""
-                      summary of the remaining log:
-                        mean            : $(mean(eachrow(log.coords)) .|> round |> Tuple)
-                        start           : $(log.coords[1, :] .|> round |> Tuple)
-                        end             : $(log.coords[end, :] .|> round |> Tuple)
-                        datetime        : $(Dates.format(log.logdate, DateFormat("yyyy-mm-dd HH:MM:SS")))
-                        number of coords: $(size(log.coords)[1])
-                      """)
+                print(
+                    """
+                    summary of the remaining log:
+                      mean            : $(mean(eachrow(log.coords)) .|> round |> Tuple)
+                      start           : $(log.coords[1, :] .|> round |> Tuple)
+                      end             : $(log.coords[end, :] .|> round |> Tuple)
+                      datetime        : $(Dates.format(log.logdate, DateFormat("yyyy-mm-dd HH:MM:SS")))
+                      number of coords: $(size(log.coords)[1])
+                    """,
+                )
                 @goto ask
             end
         elseif ans == "n" || ans == "N" || ans == ""
@@ -98,7 +100,10 @@ function interactive_edit_log(filenames...; writetofile = true)
             ans = readline()
             if ans == "y" || ans == "Y"
             elseif ans == "n" || ans == "N" || ans == ""
-                printstyled("Skip exporting to a file. Please export the returned log manually.\n", color = :magenta)
+                printstyled(
+                    "Skip exporting to a file. Please export the returned log manually.\n",
+                    color = :magenta,
+                )
                 @goto finish
             end
         end
@@ -112,3 +117,55 @@ function interactive_edit_log(filenames...; writetofile = true)
     printstyled("Edit completed.\n", color = :blue, bold = true)
     return edited_logs
 end
+
+function isplit_log!(
+    logs::AbstractVector{CoordLog{T}},
+    logid::Integer,
+    pointid::Integer,
+) where {T}
+    1 ≤ logid ≤ length(logs) ||
+        throw(ArgumentError("logid out of index: ¬ 1 ≤ $(logid) ≤ $(length(logid))"))
+    if !(1 < pointid < n_coords(logs[logid]))
+        throw(
+            ArgumentError(
+                "pointid($(pointid)) out of index: min=2, max=$(n_coords(logs[logid]) - 1)",
+            ),
+        )
+    end
+
+    log = popat!(logs, logid)
+    printstyled("note for the first log: ", color = :green, italic = true)
+    note_1 = readline()
+    printstyled("note for the second log: ", color = :green, italic = true)
+    note_2 = readline()
+    new_logs = split_log(log, pointid, note_1, note_2)
+    insert!(logs, logid, new_logs[1])
+    insert!(logs, logid + 1, new_logs[2])
+end
+
+function iedit_note!(logs::AbstractVector{CoordLog{T}}, logid::Integer) where {T}
+    1 ≤ logid ≤ length(logs) ||
+        throw(ArgumentError("logid out of index: ¬ 1 ≤ $(logid) ≤ $(length(logid))"))
+    printstyled("new note for the log: ", color = :green, italic = true)
+    note = readline()
+    logs[logid].note = note
+end
+
+function ijoin_logs!(logs::AbstractVector{CoordLog{T}}, logid1::Integer, logid2::Integer) where {T}
+    1 ≤ logid1 ≤ length(logs) ||
+        throw(ArgumentError("logid1 out of index: ¬ 1 ≤ $(logid1) ≤ $(length(logid1))"))
+    1 ≤ logid2 ≤ length(logs) ||
+        throw(ArgumentError("logid2 out of index: ¬ 1 ≤ $(logid2) ≤ $(length(logid2))"))
+    logid1 == logid2 && throw(ArgumentError("logid1 and logid2 cannot be the same"))
+    if logid1 > logid2
+        logid1, logid2 = logid2, logid1
+    end
+    
+    log_1 = popat!(logs, logid1)
+    log_2 = popat!(logs, logid2 - 1)
+    
+    printstyled("note for the new log: ", color = :green, italic = true)
+    note = readline()
+    log = join_log(log_1, log_2, note)
+    insert!(logs, logid1, log)
+end
diff --git a/src/print.jl b/src/print.jl
index f10c038..035f76c 100644
--- a/src/print.jl
+++ b/src/print.jl
@@ -11,13 +11,20 @@ function export_log(log::CoordLog)
     )"""
 end
 
-function export_log(logs::Vector{CoordLog})
+function export_log(logs::Vector{CoordLog{T}}) where {T}
     logs .|>
         export_log |>
         (vs -> join(vs, ",\n")) |>
         (s -> "[\n" * s * "\n]")
 end
 
+function export_log(logs::Vector{CoordLog{T}}, filename::AbstractString) where {T}
+    open(filename, "w") do f
+        println(f, "using Dates")
+        println(f, export_log(logs))
+    end
+end
+
 """
     export_log(io::IO, log)
 """
diff --git a/src/recipes.jl b/src/recipes.jl
index b18f1ea..813c30c 100644
--- a/src/recipes.jl
+++ b/src/recipes.jl
@@ -142,6 +142,7 @@ function Makie.plot!(tr2d::Trace2Ds)
     linesegs = Observable(Point2f[])
     points = Observable(Point2f[])
     altitudes = Observable(Float64[])
+    point_ids = Observable(Tuple{Int64, Int64}[])
     notes = Observable(String[])
     if tr2d.markercolormap[] isa Symbol
         tr2d.markercolormap[] = getproperty(ColorSchemes, tr2d.markercolormap[])
@@ -174,6 +175,7 @@ function Makie.plot!(tr2d::Trace2Ds)
         empty!(linesegs[])
         empty!(points[])
         empty!(altitudes[])
+        empty!(point_ids[])
         empty!(markercolors[])
         if linecolors[] isa AbstractVector
             empty!(linecolors[])
@@ -187,11 +189,12 @@ function Makie.plot!(tr2d::Trace2Ds)
         mcolors, mticks[] = mcolormapfunc(mcolormap, logs, tr2d.nmcolorticks[])
         for (i, log) in enumerate(logs)
             first = true
-            for point in eachrow(log.coords)
+            for (j, point) in enumerate(eachrow(log.coords))
                 push!(linesegs[], Point2f(point[1], point[3]))
                 push!(linesegs[], Point2f(point[1], point[3]))
                 push!(points[], Point2f(point[1], point[3]))
                 push!(altitudes[], point[2])
+                push!(point_ids[], (i, j))
                 push!(linecolors[], lcolors[colors_count])
                 push!(linecolors[], lcolors[colors_count])
                 push!(markercolors[], mcolors[colors_count])
@@ -256,6 +259,16 @@ function Makie.plot!(tr2d::Trace2Ds)
         markersize = tr2d.markersize,
         strokewidth = tr2d.strokewidth,
         visible = tr2d.showmarker,
+        inspector_label = (self, i, pos) -> begin
+            logid, pointid = point_ids[][i]
+            """
+            log: $(logid), point: $(pointid)
+            x: $(lpad(round(pos[1], digits = 1), 7))
+            y: $(lpad(round(altitudes[][i], digits = 1), 7))
+            z: $(lpad(round(pos[2], digits = 1), 7))
+            $(tr2d.log[][logid].note)
+            """
+        end,
     )
     # @info "dump" dump(tr2d, maxdepth = 1)
     # @info "attributes" dump(tr2d.attributes, maxdepth = 3)
diff --git a/src/typedef.jl b/src/typedef.jl
index 20ce80c..8ee6182 100644
--- a/src/typedef.jl
+++ b/src/typedef.jl
@@ -21,3 +21,7 @@ end
 Base.:(==)(x::CoordLog, y::CoordLog) = begin
     x.note == y.note && x.logdate == y.logdate && x.coords == y.coords
 end
+
+function Base.getindex(log::CoordLog{T}, i) where {T}
+    log.coords[i, :]
+end