Read!( ) not working for HDF5 file

General Usage
, ,
1

I have an HDF5 file. I want to read or allocate its data in variable r repeatedly instead of allocating in different places :seat: in memory.

using HDF5
fname = tempname(); # temporary file
fid = h5open(fname, "w")
create_group(fid, "mygroup")
fid["mydataset"] = rand(Float32, 18, 872)
r = zeros(Float32,18)
for i in 1:872
	read!((fid["mydataset"][:,1]), r)
end

i get following error.

ERROR: MethodError: no method matching read!(::Vector{Float32}, ::Vector{Float32})
The function read! exists, but no method is defined for this combination of argument types.
Closest candidates are:
read!(::IO, ::StridedArray{T}) where T
@ Base io.jl:930
read!(::IO, ::AbstractArray{T}) where T
@ Base io.jl:911
read!(::AbstractString, ::Any)
@ Base io.jl:517

How to make it read on the same place in memory to reduce allocations?

2

Does HDF5.jl provide other function for reducing allocations? How will HDF5.select_hyperslab!() work for my case?