UndefVarError after Updating to the Latest Version

ITensor Julia Questions
1

Hi, I just updated the ITensors package to the latest version. When I re-run the code which worked well with an older version, it returns an error

ERROR: UndefVarError: `MPS` not defined

where I define the type of a variable is MPS.
I also tried an example code, but it returns a similar error

julia> s = siteinds("S=1/2", 5)
ERROR: UndefVarError: `siteinds` not defined

How may I solve this problem? And I also want to read the .jld2 files that contain MPS and was given by older versions. Will updating the package fail to read the files?

Thanks!

2

MPS and siteinds have moved to ITensorMPS, have you loaded that package?

julia> using ITensors

julia> s = siteinds("S=1/2", 5)
ERROR: UndefVarError: `siteinds` not defined in `Main`
Suggestion: check for spelling errors or missing imports.
Stacktrace:
 [1] top-level scope
   @ REPL[3]:1

julia> using ITensorMPS

julia> s = siteinds("S=1/2", 5)
5-element Vector{Index{Int64}}:
 (dim=2|id=702|"S=1/2,Site,n=1")
 (dim=2|id=170|"S=1/2,Site,n=2")
 (dim=2|id=214|"S=1/2,Site,n=3")
 (dim=2|id=637|"S=1/2,Site,n=4")
 (dim=2|id=72|"S=1/2,Site,n=5")

Check out the news to see some breaking changes in each version if there’s something more thats missed

1 Like
3

Oh I didn’t add the package ITensorMPS. After using it, the code works now! Thank you!

Will check the news more frequently… Also thanks for reminding me this!

1 Like
4

It was announced here: [ANN] ITensors.jl v0.7 breaking release (MPS/MPO code moved to ITensorMPS.jl) and also here: Introduction · ITensors.jl.

1 Like
5

This topic was automatically closed 10 days after the last reply. New replies are no longer allowed.