Unexpected behavior for searchsortedlast

[kshedden]

Is this intended behavior? I am using Julia 1.3.1

julia> searchsortedlast([-2, -1, 0, 0, 1, 2], 0.0)
4 
julia> searchsortedlast([-2, -1, 0, 0, 1, 2], -0.0)
2

Version information:

julia> versioninfo() 
Julia Version 1.3.1
Commit 2d5741174c (2019-12-30 21:36 UTC)
Platform Info: 
OS: Linux (x86_64-pc-linux-gnu)
CPU: Intel(R) Xeon(R) CPU E5-2660 0 @ 2.20GHz
WORD_SIZE: 64
LIBM: libopenlibm
LLVM: libLLVM-6.0.1 (ORCJIT, sandybridge)
Environment:
JULIA_DEPOT_PATH = /nfs/kshedden/julia_libs

[haampie]

Yes, intended because

julia> isless(-0.0, 0.0)
true

julia> isless(0.0, 0.0)
false

Otherwise stick to Ints (there is no signed zero in Ints) or use < for Floats

julia> searchsortedlast([-2, -1, 0, 0, 1, 2], -0)
4

julia> searchsortedlast([-2, -1, 0, 0, 1, 2], -0.0, lt = <)
4

but do note that < on Floats is not a total order in the sense that

julia> NaN < 0
false

julia> 0 < NaN
false

so < should typically be avoided in the context of sorting unless you know your values are free of NaNs.