"""
Density matrix routines
27/08/21 v2 Updated dim handling for renaming multi-index levels + working HV plotting routines.
26/08/21 v1 Initial implementation
Dev code:
- http://100.86.127.24/jupyter/user/paul/doc/tree/github/ePSproc/notebooks/in_progress/ePSdev-PEMtk_correlations_den-mats_fn-def_260821.ipynb
- http://100.86.127.24/jupyter/user/paul/doc/tree/github/ePSproc/notebooks/in_progress/ePSdev-PEMtk_correlations_den-mats_basic-tests_220821.ipynb
"""
#*** Dim functionality (see also lmPlot() and multiDimXrToPD() functions)
# Set imports
from epsproc.util import matEleSelector
from epsproc.util.misc import checkDims
# matEdimList, BLMdimList, dataTypesList, multiDimXrToPD
# checkDims = ep.util.misc.checkDims
[docs]def dimRestack(da, stackDims = []):
"""
General Xarray restacker including multi-indexes.
Check dims in da, and restack according to refDims if necessary
Parameters
----------
da : xarray
Data array to check & restack
stackDims : str, list, dict, optional, default = []
Dimensions to check in da, and restack along if not already stacked.
Note that this can mix stacked and unstacked dims, and will restack if necessary
Returns
-------
daOut : Xarray
Data array with restacked dim.
stackedDim : str
Name of new stacked dim
rsMap : dict
Dictionary mapping for new stacked dim
dimCheck : dict
Full output from :py:func:`ep.util.misc.checkDims()`
Examples
--------
>>> # Assuming matE is a standard array of matrix elements
>>> daOut, stackedDim, rsMap, dimCheck = dimRestack(matE) # OK, returns input + dim check results
>>> daOut, stackedDim, rsMap, dimCheck = dimRestack(matE, stackDims='LM') # OK, returns original dims
>>> daOut, stackedDim, rsMap, dimCheck = dimRestack(matE, stackDims=['LM','mu']) # OK, restacks dims
Notes
-----
Passing new mappings as stackDims is currently not supported, e.g. dMap = {'NewDim':[d1,d2...]} will fail.
For this case, just use the native da.stack(dMap).
See also
--------
multiDimXrToPD() : map input array to 2D Pandas DataFrame
"""
#*** Check dims
dimCheck = checkDims(da, refDims = stackDims)
if dimCheck['missing']:
print(f"***Error: Missing specified dimension(s): {dimCheck['missing']}")
return dimsIn
#*** Restack dims if necessary
# (1) if there are both stacked and unstacked dims in denDims, unstack then restack
if dimCheck['stackedShared'] and dimCheck['shared']:
# For restack, check stacked vs. unstacked dims and assign new mapping
rsDims = [dimCheck['stackedMap'][key] for key in dimCheck['stackedShared']]
rsDims.append(dimCheck['shared']) # Append unstacked dims
rsDims = [item for sublist in rsDims for item in sublist] # Force to 1D list, https://stackoverflow.com/a/952952
# Set new map
rsMap = {','.join(rsDims):rsDims} # Assumes dim names are str, otherwise use ','.join(map(str, rsDims))
# Restack
daOut = da.unstack(dimCheck['stackedShared']).stack(rsMap)
stackedDim = next(iter(rsMap)) # list(rsMap.keys())[0] # Set name for later
# (2) for multiple single dims, restack only
elif len(dimCheck['shared'])>1:
rsDims = dimCheck['shared']
# Set new map
rsMap = {','.join(rsDims):rsDims} # Assumes dim names are str, otherwise use ','.join(map(str, rsDims))
# Restack
daOut = da.stack(rsMap)
stackedDim = next(iter(rsMap)) # list(rsMap.keys())[0] # Set name for later
# (3) if the dim is already stacked, just pass back.
else:
rsMap = {}
daOut = da
stackedDim = stackDims # Use passed dim name
return daOut, stackedDim, rsMap, dimCheck
[docs]def densityCalc(da, denDims = 'LM',
sumDims = None, keepDims = None, # May want additional control here, 1/sumDims ?
selDims = None, thres = None, squeeze = True):
r"""
General density matrix from Xarray.
Compute density matrix as (outer product) da[denDims]*da[denDims].conj(), where dim specifies the dimension(s) to use.
This is, essentially, the density matrix :math:\row = |denDims\rangle \langle denDims|:math:
Parameters
----------
da : xarray
Data array to check & restack
denDims : str, list, dict, optional, default = 'LM'
Dimensions to use as "state vector" from da.
If a single dim (including stacked dims), which exists, this will be used directly.
If multiple dims, will be restacked to a new dimension. Note that this can mix stacked and unstacked dims, and will restack if necessary.
sumDims : str, list, bool, optional, default = None
Set specific dims to sum ("trace") over.
If sumDims = True all dims, apart from denDims and keepDims, will be summed over.
keepDims : str, list, optional, default = None
Define dims to keep (won't be summed over). Only used if sumDims = True.
selDims : str, list, optional, default = None
Dimensions to subselect from.
thres : float, optional, default = None
Threshold value. If set, used for both input and output datasets.
squeeze : bool, optional, default = True
Squeeze out singleton dims if True.
Notes
-----
selDims, thres and squeeze are passed to the standard :py:func:`matEleSelector` function.
"""
# Set data
daDen = matEleSelector(da, thres = thres, inds = selDims, sq = squeeze) #.sum(sumDims)
# TODO: pass **kwargs here?
# Pass dims = denDims?
# Restack dims if required
daDen, denDim, rsMap, dimCheck = dimRestack(daDen, stackDims = denDims)
# Check for summation dims, cf. padPlot() routine
# extraDims = set(daDen.dims) - {*facetDimsCheck,*sumDims} # Check for outstanding dims, this will return an empty set if all dims accounted for here
# if extraDims:
# print(f"Found additional dims {extraDims}, summing to reduce for plot. Pass selDims to avoid.")
# for dim in extraDims:
# subset = subset.sum(dim) #.squeeze()
# Handle dim summation from input args only.
# Default is to leave all other dims untouched
if sumDims or keepDims:
# Set this to sum over all other dims (except keepDims)
if sumDims is True:
sumDims = {*daDen.dims} - {denDim}
elif not isinstance(sumDims, list): # If passed, force list
sumDims = [sumDims]
if not isinstance(keepDims, list): # If passed, force list
keepDims = [keepDims]
sumDimsCheck = set(daDen.dims)&{*sumDims} # This checks sumDims are present, otherwise will throw an error.
keepDimsCheck = set(daDen.dims)&{*keepDims}
sumTot = sumDimsCheck - keepDimsCheck # Set dims to sum
print(sumDimsCheck, keepDimsCheck, sumTot)
else:
sumTot = []
#*** Compute density from specified dims
# daDot = daDen * daDen.conj().rename({denDim:denDim+'_p'}) # Outer product along denDims
# This works, but can give issues with shared multi-index dims
# Version with renaming of multi-index dims prior to outer-product - avoids linked dims in output array.
newDims = {item:item+'_p' for item in rsMap[denDim]}
daConj = daDen.conj().unstack(denDim).rename(newDims).stack({denDim+'_p':list(newDims.values())})
daDot = daDen * daConj
# General .dot version... might be faster than above?
# matEdot = xr.dot(daDen, daDen.conj().rename({denDim:denDim+'_p'}), dims = sumDims)
daOut = matEleSelector(daDot, thres = thres, sq = squeeze).sum(sumTot) # Threshold density mat
# TODO: pass **kwargs here?
# Pass dims = denDims?
return daOut, daDot
import pandas as pd
import holoviews as hv
# import hvplot.pandas
hv.extension('bokeh')
[docs]def matPlot(da, kdims = ['LMp','LM'], pTypes = ['a','i','r'], returnType = 'plot'):
"""
General matrix (2D) plot + stacked dims plotter with HoloViews.
"""
#*** Set data
daPlot = da.copy() # May want to add thresholds etc. here?
attrs = daPlot.attrs.copy()
#*** Relabel any multi-indexes to strings.
# Without this HV plot throws errors for int category dims (kdims only?)
# TODO: check for kdims vs. stacked/selection dims?
ind = daPlot.indexes
labels = {}
for dim in ind:
# print(ind[item])
# Remap multiindex only - note this returns list not PD indexer
if isinstance(ind[dim], pd.core.indexes.multi.MultiIndex):
labels[dim] = [','.join(map(str, item)) for item in ind[dim]]
daPlot = daPlot.assign_coords({dim:labels[dim]})
# Basic version - working for any dim dataset, but single pType only
# daPlot = ep.plotTypeSelector(matEplot, pType = pType)
# hvds = hv.Dataset(daPlot)
# hvmap = hvds.to(hv.HeatMap, kdims=kdims)
# Compose HoloMap from data for r,i,a plottypes
# This only works for 2D data...? (Or case where dims are otherwise specified in loop.)
# hvmap = hv.HoloMap({pType: hv.Dataset(ep.plotTypeSelector(matEplot, pType = pType).real).to(hv.HeatMap, kdims=kdims)
# for pType in ['r','i','a']}, kdims="pType")
# Example with continuum included too - should be able to generalise?
# hvmap = hv.HoloMap({(cont,pType): hv.Dataset(ep.plotTypeSelector(matEplot.sel(Cont=cont), pType = pType).squeeze(drop=True).real).to(hv.HeatMap, kdims=['LMp','LM'])
# for pType in ['r','i','a'] for cont in ['A2','B1','B2']}, kdims=['Cont',"pType"])
# Stack to xr.Dataset for pTypes...
# NOTE .copy() here, otherwise end up with null valued output (overwrites/sums?)
daPlotDS = xr.Dataset({pType:ep.plotTypeSelector(daPlot.copy(), pType = pType) for pType in pTypes}) #['r','i','a']})
daPlot = daPlotDS.to_array().rename({'variable':'pType'}) # Restack pType to array
daPlot.attrs = attrs # Propagate attrs
daPlot.name = da.name
hvds = hv.Dataset(daPlot)
hvmap = hvds.to(hv.HeatMap, kdims=kdims)
if returnType is 'full':
return hvmap, hvds, daPlotDS
else:
return hvmap