Improve show for Qobj/QobjEvo lists

[ytdHuang]

Checklist

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Description

The current show for Qobj tuples print as the following style:

julia> a = destroy(2);
julia> (a, a', a + a')
(Quantum Object:   type=Operator   dims=[2]   size=(2, 2)   ishermitian=false
2×2 SparseMatrixCSC{ComplexF64, Int64} with 1 stored entry:
     ⋅      1.0+0.0im
     ⋅          ⋅    , Quantum Object:   type=Operator   dims=[2]   size=(2, 2)   ishermitian=false
2×2 Adjoint{ComplexF64, SparseMatrixCSC{ComplexF64, Int64}} with 1 stored entry:
     ⋅          ⋅    
 1.0-0.0im      ⋅    , Quantum Object:   type=Operator   dims=[2]   size=(2, 2)   ishermitian=true
2×2 SparseMatrixCSC{ComplexF64, Int64} with 2 stored entries:
     ⋅      1.0+0.0im
 1.0+0.0im      ⋅    )

julia> (a, QobjEvo(a))
(Quantum Object:   type=Operator   dims=[2]   size=(2, 2)   ishermitian=false
2×2 SparseMatrixCSC{ComplexF64, Int64} with 1 stored entry:
     ⋅      1.0+0.0im
     ⋅          ⋅    , Quantum Object Evo.:   type=Operator   dims=[2]   size=(2, 2)   ishermitian=false   isconstant=true
MatrixOperator(2 × 2))

With this PR, every Qobj / QobjEvo prints from a new line, that is:

julia> (a, a', a + a')
(
Quantum Object:   type=Operator   dims=[2]   size=(2, 2)   ishermitian=false
2×2 SparseMatrixCSC{ComplexF64, Int64} with 1 stored entry:
     ⋅      1.0+0.0im
     ⋅          ⋅    , 
Quantum Object:   type=Operator   dims=[2]   size=(2, 2)   ishermitian=false
2×2 Adjoint{ComplexF64, SparseMatrixCSC{ComplexF64, Int64}} with 1 stored entry:
     ⋅          ⋅    
 1.0-0.0im      ⋅    , 
Quantum Object:   type=Operator   dims=[2]   size=(2, 2)   ishermitian=true
2×2 SparseMatrixCSC{ComplexF64, Int64} with 2 stored entries:
     ⋅      1.0+0.0im
 1.0+0.0im      ⋅    )

julia> (a, QobjEvo(a))
(
Quantum Object:   type=Operator   dims=[2]   size=(2, 2)   ishermitian=false
2×2 SparseMatrixCSC{ComplexF64, Int64} with 1 stored entry:
     ⋅      1.0+0.0im
     ⋅          ⋅    , 
Quantum Object Evo.:   type=Operator   dims=[2]   size=(2, 2)   ishermitian=false   isconstant=true
MatrixOperator(2 × 2))

This is useful when checking the c_ops, e_ops, and so on, when they are in Tuple type.

Also, for Vector and SVector:

julia> [a, a', a + a']
3-element Vector{QuantumObject{MT, OperatorQuantumObject, 1} where MT<:AbstractArray}:
 
Quantum Object:   type=Operator   dims=[2]   size=(2, 2)   ishermitian=false
2×2 SparseMatrixCSC{ComplexF64, Int64} with 1 stored entry:
     ⋅      1.0+0.0im
     ⋅          ⋅    
 
Quantum Object:   type=Operator   dims=[2]   size=(2, 2)   ishermitian=false
2×2 Adjoint{ComplexF64, SparseMatrixCSC{ComplexF64, Int64}} with 1 stored entry:
     ⋅          ⋅    
 1.0-0.0im      ⋅    
 
Quantum Object:   type=Operator   dims=[2]   size=(2, 2)   ishermitian=true
2×2 SparseMatrixCSC{ComplexF64, Int64} with 2 stored entries:
     ⋅      1.0+0.0im
 1.0+0.0im      ⋅

julia> SVector{3}([a, a', a + a'])
3-element SVector{3, QuantumObject{MT, OperatorQuantumObject, 1} where MT<:AbstractArray} with indices SOneTo(3):
 
Quantum Object:   type=Operator   dims=[2]   size=(2, 2)   ishermitian=false
2×2 SparseMatrixCSC{ComplexF64, Int64} with 1 stored entry:
     ⋅      1.0+0.0im
     ⋅          ⋅    
 
Quantum Object:   type=Operator   dims=[2]   size=(2, 2)   ishermitian=false
2×2 Adjoint{ComplexF64, SparseMatrixCSC{ComplexF64, Int64}} with 1 stored entry:
     ⋅          ⋅    
 1.0-0.0im      ⋅    
 
Quantum Object:   type=Operator   dims=[2]   size=(2, 2)   ishermitian=true
2×2 SparseMatrixCSC{ComplexF64, Int64} with 2 stored entries:
     ⋅      1.0+0.0im
 1.0+0.0im      ⋅

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 93.14%. Comparing base (270d3f6) to head (22bbfb9).
Report is 3 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #365   +/-   ##
=======================================
  Coverage   93.14%   93.14%           
=======================================
  Files          41       41           
  Lines        2684     2684           
=======================================
  Hits         2500     2500           
  Misses        184      184           

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[albertomercurio]

Don't we simply fix it if we define the Base.show method with a break line at the end?

[ytdHuang]

Don't we simply fix it if we define the Base.show method with a break line at the end?

If we add \n after showing AbstractQuantumObject, it will become:

(Quantum Object:   type=Operator   dims=[2]   size=(2, 2)   ishermitian=false
2×2 SparseMatrixCSC{ComplexF64, Int64} with 1 stored entry:
     ⋅      1.0+0.0im
     ⋅          ⋅    
, Quantum Object:   type=Operator   dims=[2]   size=(2, 2)   ishermitian=false
2×2 Adjoint{ComplexF64, SparseMatrixCSC{ComplexF64, Int64}} with 1 stored entry:
     ⋅          ⋅    
 1.0-0.0im      ⋅    
, Quantum Object:   type=Operator   dims=[2]   size=(2, 2)   ishermitian=true
2×2 SparseMatrixCSC{ComplexF64, Int64} with 2 stored entries:
     ⋅      1.0+0.0im
 1.0+0.0im      ⋅    
)

which the comma , will be in the beginning of the line.

So I think it would be better to add it before.

Also, this separates the output of the first two lines of Vector{Qobj}, namely

julia> [a, a', a + a']
3-element Vector{QuantumObject{MT, OperatorQuantumObject, 1} where MT<:AbstractArray}:
 
Quantum Object:   type=Operator   dims=[2]   size=(2, 2)   ishermitian=false
...

[albertomercurio]

Ok, you just did the opposite, i.e. suing a line break in the beginning, right?

[ytdHuang]

Ok, you just did the opposite, i.e. suing a line break in the beginning, right?

Yes, that's all I did.
The rest of the changes are for the doctests.