Hi Bhavya,
The error you are seeing is because for some reason the linear system
you're solving has real inputs. Scattering problems are almost never
real, and therefore we didn't bother to support this in the code.
Moreover internally Kwant never produces linear problems that are of
real data type and not complex. Are you using a different package to
generate a Kwant problem?
Best,
Anton
On Sun, 13 Jun 2021 at 22:42, BHAVYA BHARDWAJ <bhavya1...@yahoo.com> wrote:
>
> Repected Members,
>
> I am a B.Tech Student using Kwant for simulations.
> Python Version: 3.7.8
> Kwant Version: 1.4.2
> Ubuntu 20
> The Error I faced is given below.
>
> AttributeError Traceback (most recent call last)
> <ipython-input-6-c80da766c4bb> in <module>
> 17 pyplot.ylabel("conductance [e^2/h]")
> 18 pyplot.show()
> ---> 19 solving(model.tokwant())
>
> <ipython-input-6-c80da766c4bb> in solving(sys)
> 7 energy = ie * 0.01
> 8 # compute the scattering matrix at a given energy
> ----> 9 smatrix = kwant.greens_function(sys,
> energy,check_hermiticity=False)
> 10 # compute the transmission probability from lead 0 to
> 11 # lead 1
>
> ~/Downloads/112358/lib/python3.7/site-packages/kwant/_common.py in
> inner(*args, **kwargs)
> 70 if sig.bind(*args,
> **kwargs).arguments.get(parameter_name):
> 71 warn()
> ---> 72 return f(*args, **kwargs)
> 73
> 74 return inner
>
> ~/Downloads/112358/lib/python3.7/site-packages/kwant/solvers/common.py in
> greens_function(self, sys, energy, args, out_leads, in_leads,
> check_hermiticity, params)
> 485 rhs = sp.bmat([[i for i in linsys.rhs if i.shape[1]]],
> 486 format=self.rhsformat)
> --> 487 flhs = self._factorized(linsys.lhs)
> 488 data = self._solve_linear_sys(flhs, rhs, kept_vars)
> 489
>
> ~/Downloads/112358/lib/python3.7/site-packages/kwant/solvers/mumps.py in
> _factorized(self, a)
> 102 def _factorized(self, a):
> 103 inst = mumps.MUMPSContext()
> --> 104 inst.factor(a, ordering=self.ordering)
> 105 return inst
> 106
>
> ~/Downloads/112358/lib/python3.7/site-packages/kwant/linalg/mumps.py in
> factor(self, a, ordering, ooc, pivot_tol, reuse_analysis, overwrite_a)
> 318 row, col,
> data)
> 319 else:
> --> 320 self.analyze(a, ordering=ordering,
> overwrite_a=overwrite_a)
> 321
> 322 self.mumps_instance.icntl[22] = 1 if ooc else 0
>
> ~/Downloads/112358/lib/python3.7/site-packages/kwant/linalg/mumps.py in
> analyze(self, a, ordering, overwrite_a)
> 227
> 228 if dtype != self.dtype:
> --> 229 self.mumps_instance = getattr(_mumps,
> dtype+"mumps")(self.verbose)
> 230 self.dtype = dtype
> 231
>
> AttributeError: module 'kwant.linalg._mumps' has no attribute 'dmumps'
>
>
> Kindly guide me so I can overcome this error.
>
>
> Thank You,
>
> Regards,
>
> Bhavya Bhardwaj
>
>
>
