WIP: Block System

[Roger-luo]

Interface of AbstractBlock

Properties

• nqubits number of qubits
• cache_level cache level of this block
• full get this block's dense matrix form
• sparse get this block's sparse matrix form

Methods

• apply! apply this block to a register
• update! update parameters according to given sequence
• cache! force cache all blocks that under given cache level

[coveralls]

Pull Request Test Coverage Report for Build 83

• 186 of 229 (81.22%) changed or added relevant lines in 6 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-13.01%) to 83.764%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/Blocks/Core.jl	36	37	97.3%
src/Blocks/Measure.jl	0	1	0.0%
src/Register.jl	9	15	60.0%
src/Blocks/Cache.jl	15	23	65.22%
src/Blocks/Compose.jl	98	125	78.4%

Totals
Change from base Build 71:	-13.01%
Covered Lines:	227
Relevant Lines:	271

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💛 - Coveralls

[codecov-io]

Codecov Report

Merging #11 into master will decrease coverage by 63.37%.
The diff coverage is 2.72%.

@@             Coverage Diff             @@
##           master      #11       +/-   ##
===========================================
- Coverage     100%   36.62%   -63.38%     
===========================================
  Files           3        8        +5     
  Lines          60      172      +112     
===========================================
+ Hits           60       63        +3     
- Misses          0      109      +109

Impacted Files	Coverage Δ
src/QuCircuit.jl	100% <ø> (ø)	⬆️
src/Register.jl	85.96% <0%> (-14.04%)	⬇️
src/Blocks/Cache.jl	0% <0%> (ø)
src/Blocks/Compose.jl	0% <0%> (ø)
src/Blocks/Measure.jl	0% <0%> (ø)
src/Blocks/Core.jl	0% <0%> (ø)
src/Blocks/Primitive.jl	30% <30%> (ø)
... and 3 more

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[Roger-luo]

Refactor composite blocks

abstract type hierarchy:

abstract type AbstractBlock{N} end
abstract type LeafBlock{N} <: AbstractBlock{N} end
abstract type AbstractGate{N} <: LeafBlock{N} end

Do we still need a abstract block for unitaries?

abstract type UnitaryBlock{N} <: AbstractBlock{N} end

Concentrator is removed from composite blocks, composite blocks now only contains ChainBlock, KronBlock, these two are unitaries.

ChainBlock <: UnitaryBlock # or AbstractBlock
KronBlock <: UnitaryBlock # or AbstractBlock

ChainBlock

ChainBlock now checks its contents' shape.

KronBlock

Can KronBlock takes a Concentrator as its sub-block? I don't think so. Concentrator itself can not kroneckered with other unitaries. Therefore, a UnitaryBlock could be necessary for this type check.

Measure

Measure will only be implemented as a method:

• measure(reg, address)->bitstring measure a result (a bit string), but do not change the original register state
• measure!(reg, address)->bitstring, reg measure a result (a bit string), and change the register state (to an eigen state)
• measure_remove(reg, address) -> new_reg measure a result and trace the qubits

@GiggleLiu

[Roger-luo]

Another change, since Concentrator is actually a rank-3 tensor, but the full & sparse methods are supposed to return a matrix (unitary) from block, it will now only return a subtype of UnitaryBlock's matrix.

the matrix form of ChainBlock will be implemented to be able to generate unitary with correct size when it contains several Concentrator with correct shape.

[Roger-luo]

const UnitaryBlock = Union{AbstractGate, ChainBlock, KronBlock}

[Roger-luo]

Cache Level

Add a new type parameter for each block types to specify its cache level. The block interface is extended to

apply!(block, reg, cache_level=0) # do not cache by default
cache!(block, level) # requires level, force update all the cache
dispatchin!(block, params) # dispatch params in block