From 15dd582aad98f761b90530e7cbbdc463ed310e9e Mon Sep 17 00:00:00 2001
From: F Freyer <frederic481994@hotmail.de>
Date: Sat, 22 Aug 2020 15:21:57 +0200
Subject: [PATCH 1/2] add LogBinner(LogBinner)

---
 src/log/binning.jl | 15 +++++++++++++--
 test/logbinning.jl | 20 ++++++++++++++++++++
 2 files changed, 33 insertions(+), 2 deletions(-)

diff --git a/src/log/binning.jl b/src/log/binning.jl
index 1310635..0194f8b 100644
--- a/src/log/binning.jl
+++ b/src/log/binning.jl
@@ -204,8 +204,6 @@ function LogBinner(x::T;
     return B
 end
 
-
-
 function _sum_type_heuristic(::Type{T}, elndims::Integer) where T
     # heuristic to set sum type (#2)
     S = if eltype(T)<:Real
@@ -216,6 +214,19 @@ function _sum_type_heuristic(::Type{T}, elndims::Integer) where T
     return S
 end
 
+function LogBinner(B::LogBinner{S, M}, capacity::Int64 = _nlvls2capacity(32)) where {S, M}
+    N = _capacity2nlvls(capacity)
+    el = zero(B.x_sum[1])
+    
+    LogBinner{S, N}(
+        tuple([i > M ? Compressor{S}(copy(el), false) : deepcopy(B.compressors[i]) for i in 1:N]...),
+        [i > M ? copy(el) : copy(B.x_sum[i]) for i in 1:N],
+        [i > M ? copy(el) : copy(B.x2_sum[i]) for i in 1:N],
+        [i > M ? 0 : copy(B.count[i]) for i in 1:N]
+    )
+end
+
+
 
 # TODO typing?
 """
diff --git a/test/logbinning.jl b/test/logbinning.jl
index cb600d1..71d8fc5 100644
--- a/test/logbinning.jl
+++ b/test/logbinning.jl
@@ -13,6 +13,10 @@
         @test B == B2
         @test !(B != B2)
 
+        B3 = LogBinner(B, 10_000)
+        @test B3 == B
+        @test capacity(B3) == 16383
+
         buffer = rand(1000)
         append!(B, buffer)
         @test length(B) == 1000
@@ -20,6 +24,12 @@
         @test !(B == B2)
         @test B != B2
 
+        @test B3 != B
+        @test isempty(B3)
+        B3 = LogBinner(B, 10_000)
+        @test B3 == B
+        @test !isempty(B3)
+
         append!(B2, buffer)
         @test B == B2
         @test !(B != B2)
@@ -43,6 +53,10 @@
         @test B == B2
         @test !(B != B2)
 
+        B3 = LogBinner(B, 10_000)
+        @test B3 == B
+        @test capacity(B3) == 16383
+
         buffer = [rand(T, 2, 3) for _ in 1:1000]
         append!(B, buffer)
         @test length(B) == 1000
@@ -50,6 +64,12 @@
         @test !(B == B2)
         @test B != B2
 
+        @test B3 != B
+        @test isempty(B3)
+        B3 = LogBinner(B, 10_000)
+        @test B3 == B
+        @test !isempty(B3)
+
         append!(B2, buffer)
         @test B == B2
         @test !(B != B2)

From d9f7d275773c434fb3a665187e2e76e58e110332 Mon Sep 17 00:00:00 2001
From: F Freyer <frederic481994@hotmail.de>
Date: Sat, 22 Aug 2020 15:38:58 +0200
Subject: [PATCH 2/2] add docstring, Overflow check

---
 src/log/binning.jl | 12 +++++++++++-
 test/logbinning.jl | 10 ++++++----
 2 files changed, 17 insertions(+), 5 deletions(-)

diff --git a/src/log/binning.jl b/src/log/binning.jl
index 0194f8b..4d759bf 100644
--- a/src/log/binning.jl
+++ b/src/log/binning.jl
@@ -214,8 +214,18 @@ function _sum_type_heuristic(::Type{T}, elndims::Integer) where T
     return S
 end
 
-function LogBinner(B::LogBinner{S, M}, capacity::Int64 = _nlvls2capacity(32)) where {S, M}
+"""
+    LogBinner(B::LogBinner[; capacity::Int])
+
+Creates a new `LogBinner` from an existing LogBinner, copying the data inside.
+The new LogBinner may be larger or smaller than the given one.
+"""
+function LogBinner(B::LogBinner{S, M}; capacity::Int64 = _nlvls2capacity(32)) where {S, M}
     N = _capacity2nlvls(capacity)
+    B.count[min(M, N)] > 0 && throw(OverflowError(
+        "The new LogBinner is too small to reconstruct the given LogBinner. " *
+        "New capacity = $capacity   Old capacity = $(B.count[min(M, N)])"
+    ))
     el = zero(B.x_sum[1])
     
     LogBinner{S, N}(
diff --git a/test/logbinning.jl b/test/logbinning.jl
index 71d8fc5..0ba8f45 100644
--- a/test/logbinning.jl
+++ b/test/logbinning.jl
@@ -13,7 +13,7 @@
         @test B == B2
         @test !(B != B2)
 
-        B3 = LogBinner(B, 10_000)
+        B3 = LogBinner(B, capacity=10_000)
         @test B3 == B
         @test capacity(B3) == 16383
 
@@ -26,7 +26,8 @@
 
         @test B3 != B
         @test isempty(B3)
-        B3 = LogBinner(B, 10_000)
+        @test_throws OverflowError LogBinner(B, capacity=10)
+        B3 = LogBinner(B, capacity=10_000)
         @test B3 == B
         @test !isempty(B3)
 
@@ -53,7 +54,7 @@
         @test B == B2
         @test !(B != B2)
 
-        B3 = LogBinner(B, 10_000)
+        B3 = LogBinner(B, capacity=10_000)
         @test B3 == B
         @test capacity(B3) == 16383
 
@@ -66,7 +67,8 @@
 
         @test B3 != B
         @test isempty(B3)
-        B3 = LogBinner(B, 10_000)
+        @test_throws OverflowError LogBinner(B, capacity=10)
+        B3 = LogBinner(B, capacity=10_000)
         @test B3 == B
         @test !isempty(B3)