Dale Black (Jun 17 2021 at 20:47): Dale Black (Jun 17 2021 at 20:47):Say I have two arrays of Floats, is there a way to compare them using the bitwise and operator .& or some other operator?
ŷ .& y
The above works for Int and Bool but not Floats
Dale Black (Jun 17 2021 at 20:50):Or maybe a better question, is there a better way to convert Floats to integers?
Here is the full code and I am getting an inexact error when I try to run this
function dice_metric(ŷ, y)
ŷ, y = Int64.(ŷ), Int64.(y)
dice = 2 * sum((ŷ .& y)) / (sum(ŷ) + sum(y))
return dice
end
InexactError: Int64(-5.5319665e-6)
Stacktrace:
[1] Int64
@ ./float.jl:723 [inlined]
[2] _broadcast_getindex_evalf
@ ./broadcast.jl:648 [inlined]
[3] _broadcast_getindex
@ ./broadcast.jl:621 [inlined]
[4] getindex
@ ./broadcast.jl:575 [inlined]
[5] macro expansion
@ ./broadcast.jl:984 [inlined]
[6] macro expansion
@ ./simdloop.jl:77 [inlined]
[7] copyto!
@ ./broadcast.jl:983 [inlined]
[8] copyto!
@ ./broadcast.jl:936 [inlined]
[9] copy
@ ./broadcast.jl:908 [inlined]
[10] materialize
@ ./broadcast.jl:883 [inlined]
[11] dice_metric(ŷ::Array{Float32, 4}, y::Array{Float32, 4})
@ Main ./In[28]:2
[12] top-level scope
@ In[37]:39
[13] eval
@ ./boot.jl:360 [inlined]
[14] include_string(mapexpr::typeof(REPL.softscope), mod::Module, code::String, filename::String)
@ Base ./loading.jl:1094
What's a true floating point value to you?
Matt Bauman (Jun 17 2021 at 20:51):all nonzeros?
Dale Black (Jun 17 2021 at 20:52):Yes I am working with binary arrays currently so that should be correct
Matt Bauman (Jun 17 2021 at 20:53):what's a binary array?
Matt Bauman (Jun 17 2021 at 20:53):In any case, I think I'd do @. !iszero(ŷ) & !iszero(y)
Mason Protter (Jun 17 2021 at 20:55):To me, this is what I think of when I think of bitwise and between floats:
julia> x = rand(5)
5-element Vector{Float64}:
0.4136385097187676
0.8561170860323639
0.5673269657861939
0.3364253326881379
0.2945387286498147
julia> y = rand(5)
5-element Vector{Float64}:
0.6559688998496613
0.033461184123736
0.6446603481441768
0.9123783704466826
0.7033529950179171
julia> reinterpret(UInt64, x) .& reinterpret(UInt64, y)
5-element Vector{UInt64}:
0x3fc0790025808400
0x3fa1214300c04100
0x3fe0210aa1001082
0x3fc502341e540000
0x3fc2819823a42004
julia> reinterpret(Float64, ans)
5-element reinterpret(Float64, ::Vector{UInt64}):
0.1286926444163612
0.03345689186255818
0.5040333885704202
0.16412974816194037
0.14457990398682352
Yeah, I think you're after logical &&, not bitwise &
Dale Black (Jun 17 2021 at 21:04):Okay I will do some investigating because I realize now I don't really understand bitwise and
chriselrod (Jun 21 2021 at 15:47):julia> bitstring(0x55)
"01010101"
julia> bitstring(0x0f)
"00001111"
julia> bitstring(0x55 & 0x0f)
"00000101"
Bitwise & does & between the individual bits of the number.
Dale Black (Jun 22 2021 at 02:16):Okay, it looks like bitwise & is actually what I am looking for then. I just need to figure out the best way to turn an array of numbers into a binary array of zeros and ones after they go through a training loop
Dale Black (Jun 22 2021 at 02:16):I'm simply trying to use this dice_metric
function dice_metric(ŷ, y)
dice = 2 * sum(ŷ .& y) / (sum(ŷ) + sum(y))
return dice
end
I will go with this for now since it seems to work fine
function as_discrete(array, logit_threshold)
array = array .>= logit_threshold
return array
end
Last updated: Oct 02 2023 at 04:34 UTC