[ITensors] [BUG] Compilation using ``ITensors.compile()`` doesn't work; "No method is defined..."

[jaredjeya]

Description of bug

When running ITensors.compile(), as detailed here, I get an error: the method doesn't seem to be found. The code in compile.jl seems to be missing: see here

Minimal code demonstrating the bug or unexpected behavior

Minimal runnable code

using ITensors
ITensors.compile()

Expected output or behavior

ITensor compiles without issue.

Actual output or behavior

Output of minimal runnable code

julia> ITensors.compile()
ERROR: MethodError: no method matching compile(::NDTensors.BackendSelection.Algorithm{:PackageCompiler, @NamedTuple{}})
The function `compile` exists, but no method is defined for this combination of argument types.

Closest candidates are:
  compile(; backend, kwargs...)
   @ ITensors ~/.julia/packages/ITensors/HwzqQ/src/packagecompile/compile.jl:39

Stacktrace:
 [1] compile(; backend::NDTensors.BackendSelection.Algorithm{:PackageCompiler, @NamedTuple{}}, kwargs::@Kwargs{})
   @ ITensors ~/.julia/packages/ITensors/HwzqQ/src/packagecompile/compile.jl:40
 [2] compile()
   @ ITensors ~/.julia/packages/ITensors/HwzqQ/src/packagecompile/compile.jl:39
 [3] top-level scope
   @ REPL[7]:1

Version information

• Output from versioninfo():

julia> versioninfo()
Julia Version 1.11.2
Commit 5e9a32e7af2 (2024-12-01 20:02 UTC)
Build Info:
  Official https://julialang.org/ release
Platform Info:
  OS: Linux (x86_64-linux-gnu)
  CPU: 48 × Intel(R) Xeon(R) CPU E5-2650 v4 @ 2.20GHz
  WORD_SIZE: 64
  LLVM: libLLVM-16.0.6 (ORCJIT, broadwell)
Threads: 48 default, 0 interactive, 24 GC (on 48 virtual cores)

• Output from using Pkg; Pkg.status("ITensors"):

julia> using Pkg; Pkg.status("ITensors")
Status `/storage/slow_raid5/SYSTEM/localhome/phyjj/[redacted]/Project.toml`
  [9136182c] ITensors v0.7.8

[mtfishman]

Please try loading ITensorMPS.jl before running ITensors.compile(), the compilation relies on running DMRG which is now in ITensorMPS.jl. See https://itensor.github.io/ITensors.jl/dev/#News.

[jaredjeya]

Thanks, I’ll try that.

Can you update the documentation to reflect that please, since it’s currently not clear? (A quick google for the error I had wasn’t helpful either)

[mtfishman]

Sure, will do.

[jaredjeya]

This actually still doesn't work for me. I'm doing exactly what you've put in the new docs, i.e.

using ITensors, ITensorMPS
ITensors.compile()

but I get the same error.

I've also replicated this error on three different machines (one Windows, two Linux).

[mtfishman]

Oops, sorry about that. I forgot you also have to install and load PackageCompiler.jl since the functionality was moved to a package extension so that we don't force everyone to install PackageCompiler.jl even if they don't want to use ITensors.compile().

So this should work:

using ITensors, ITensorMPS
using PackageCompiler
ITensors.compile()

I'll clarify that in the docs.

[jaredjeya]

Thanks, seems to be working now!