Solved scaling problem, but still noise in ac
Corrected errors in relaxation and imp. peak check
Find roots of multiple determinants still unsolved

see file: todo
Vast output for invesigating root search

Commented out calcAcSub for spin upp in calcAc routine
See todo file for status report
Cleared up subcond and implemented tests

no non-mirror-symmetric findRoot/getPoles/getWeights routines in
subcond.cpp yet.
Completed restructuring of subcond with templates

Also more convenient test.cpp
Determinant scaling variable outside of subcond

The calculation of the determinant scaling factor ~t^(N-1)
is now performed each time the getA routine is called. (Previously
it was calculated each time the find_root routine was called).
Added multiple precision for the root search

------- Introduced multiple precision arithmetic via the

	gnu mpfr library

	and the corresponding C++ wrapper library

	mpfr++ (mpreal)

------- Scale and precision is now calculated at each call of the routines

	get_poles
	get_poles_and_weights

	from subcond.h (wrappers for multiple precision routines)

------- Added python routine for conversion of muliple precision data to
	standard double (long double) precision data by linear transformation
	(zooming in): mpconvert.py
Corrected false calculation of weights

--- Corrected false calculation of weights to calculation using
    residues. (Not yet tested).

--- Updated mpconvert.py

--- Changed 'output' class in order to read in omega code from file

--- Included calculation of conduction band spectral densities in
    test routine
Updated new version of weights in subeuo.cpp
Introduced output class for testing purposes
Restructured subcond.cpp

--- In the calculation of the conduction band electron Green's function
    two differnent cases are implemented:

    1.) Imaginary part of selfengergy is large (>=zeta=1E-10):
    Find poles of the Green's function (roots of the determinant of the
    inverse Green's function matrix) by calculating in double precision.
    If two neighboring roots are very narrow, they may not be resolved
    in double precision. Since the position of the poles are used as
    the position of cluster points in an integration grid, such an
    extremum is treated as two roots at the same position.

    2.) Imaginary part of selfengergy is small (<zeta=1E-10):
    Since the difference of two neighboring roots can be up to t^N-1
    (with t: hopping, N: number of layers). On has to use mulitple
    precision calculation in order to resolve the exact position of
    these roots. This is done by using the GNU mpfr library and the
    C++ wrapper mpreal. The precision is chosen such, that t^N-1 can
    be resolved. The performance is much worse than in the double
    precision case. Also the resulting weights seem to be faulty
    (see below).

--- The calculation of the conduction band Green's function for small
    imaginary parts of the selfenergy is still not possible. For now,
    this problem is circumvented by introducing the small artificial
    constant imaginary part of the selfenergy eta.

    The problem is, that the calculated weights seem to have an error.
    This may be connected to the fact, that very small differences in
    the denominator of the weights are calculated. To see the problem
    one can plot the weights against omega. To do so, one has to
    uncomment the lines 952-953, 958-965 and 1012-1019 in subeuo.cpp
    and call calcAcSub once with mirror symmetry on and vanishing
    imaginary part of the selfenergy.

    The program will abort if the selfenergy is to small. Therefore
    the default value for eta was changed to zeta=1E-10
Corrected false dn-calculation for the pure case

Also set eta to 2E-10 to ensure >1E-10 after numerical arithmetic
Switched back to delta distribution calc. of Ac

Switched back to calculation of the conduction band Green's function
via the delta distribution function formula (not yet analytically
proven) in the case of vanishing imaginary part of the conduction
band selfenergy.