diff --git a/nifty5/library/adjust_variances.py b/nifty5/library/adjust_variances.py
index 7cbc98c9fe7afe357404fc2384696cc79abe95e5..6089a6882af10c2fce1583ee05f56831549fdaff 100644
--- a/nifty5/library/adjust_variances.py
+++ b/nifty5/library/adjust_variances.py
@@ -18,7 +18,8 @@
 from ..minimization.energy_adapter import EnergyAdapter
 from ..multi_field import MultiField
 from ..operators.distributors import PowerDistributor
-from ..operators.energy_operators import StandardHamiltonian, InverseGammaLikelihood
+from ..operators.energy_operators import (StandardHamiltonian,
+                                          InverseGammaLikelihood)
 from ..operators.scaling_operator import ScalingOperator
 from ..operators.simple_linear_operators import ducktape
 
@@ -72,7 +73,8 @@ def make_adjust_variances(a,
     if scaling is not None:
         x = ScalingOperator(scaling, x.target)(x)
 
-    return StandardHamiltonian(InverseGammaLikelihood(d_eval/2.)(x), ic_samp=ic_samp)
+    return StandardHamiltonian(InverseGammaLikelihood(d_eval/2.)(x),
+                               ic_samp=ic_samp)
 
 
 def do_adjust_variances(position,
diff --git a/nifty5/library/smooth_linear_amplitude.py b/nifty5/library/smooth_linear_amplitude.py
index 1b525b2607bcad3da5dcb40bc6a993f3470e58bc..5421cc09b4814932f83a1b5f747c9e1e147257b4 100644
--- a/nifty5/library/smooth_linear_amplitude.py
+++ b/nifty5/library/smooth_linear_amplitude.py
@@ -138,7 +138,8 @@ def SLAmplitude(*, target, n_pix, a, k0, sm, sv, im, iv, keys=['tau', 'phi']):
     of the linear function.
 
     The prior on the smooth component is parametrized by two real numbers: the
-    strength and the cutoff of the smoothness prior (see :class:`CepstrumOperator`).
+    strength and the cutoff of the smoothness prior
+    (see :class:`CepstrumOperator`).
 
     Parameters
     ----------
diff --git a/nifty5/operators/contraction_operator.py b/nifty5/operators/contraction_operator.py
index 2a2a2e557c248ad173a63b5c12933c543439de56..e790cc47945aedd31c5af4523608ced1e59d2164 100644
--- a/nifty5/operators/contraction_operator.py
+++ b/nifty5/operators/contraction_operator.py
@@ -24,7 +24,8 @@ from .linear_operator import LinearOperator
 
 
 class ContractionOperator(LinearOperator):
-    """A  :class:`LinearOperator` which sums up fields into the direction of subspaces.
+    """A  :class:`LinearOperator` which sums up fields into the direction of
+    subspaces.
 
     This Operator sums up a field with is defined on a :class:`DomainTuple`
     to a :class:`DomainTuple` which contains the former as a subset.
diff --git a/nifty5/operators/endomorphic_operator.py b/nifty5/operators/endomorphic_operator.py
index 16afb73749479c58fab9abe1fd52f5c32824aab9..008f94c2907888b3ac99ff43a707404a5d8e267c 100644
--- a/nifty5/operators/endomorphic_operator.py
+++ b/nifty5/operators/endomorphic_operator.py
@@ -21,8 +21,8 @@ from .linear_operator import LinearOperator
 
 
 class EndomorphicOperator(LinearOperator):
-    """Represents a :class:`LinearOperator` which is endomorphic, i.e. one which
-    has identical domain and target.
+    """Represents a :class:`LinearOperator` which is endomorphic, i.e. one
+    which has identical domain and target.
     """
     @property
     def target(self):
diff --git a/nifty5/operators/linear_interpolation.py b/nifty5/operators/linear_interpolation.py
index 652419b8e26ce4f42c889efd2fcca12ecdd7c3d3..b6c1b89ddb48befba65450ee39ee596d8de4d727 100644
--- a/nifty5/operators/linear_interpolation.py
+++ b/nifty5/operators/linear_interpolation.py
@@ -53,9 +53,8 @@ class LinearInterpolator(LinearOperator):
 
         # FIXME This needs to be removed as soon as the bug below is fixed.
         if dims.count(dims[0]) != len(dims):
-            raise TypeError(
-                'This is a bug. Please extend LinearInterpolators functionality!'
-            )
+            raise TypeError("This is a bug. Please extend"
+                            "LinearInterpolator's functionality!")
 
         shp = sampling_points.shape
         if not (isinstance(sampling_points, np.ndarray) and len(shp) == 2):
diff --git a/nifty5/operators/sampling_enabler.py b/nifty5/operators/sampling_enabler.py
index 57327368ea201059d31bf2a5de2e32b08333502e..25d28131982d188570f0f9fab35b5588f18cf868 100644
--- a/nifty5/operators/sampling_enabler.py
+++ b/nifty5/operators/sampling_enabler.py
@@ -38,10 +38,10 @@ class SamplingEnabler(EndomorphicOperator):
         The iteration controller to use for the iterative numerical inversion
         done by a :class:`ConjugateGradient` object.
     approximation : :class:`LinearOperator`, optional
-        if not None, this linear operator should be an approximation to the operator, which
-        supports the operation modes that the operator doesn't have. It is used as a
-        preconditioner during the iterative inversion, to accelerate
-        convergence.
+        if not None, this linear operator should be an approximation to the
+        operator, which supports the operation modes that the operator doesn't
+        have. It is used as a preconditioner during the iterative inversion,
+        to accelerate convergence.
     """
 
     def __init__(self, likelihood, prior, iteration_controller,
diff --git a/nifty5/operators/simple_linear_operators.py b/nifty5/operators/simple_linear_operators.py
index c98a9c20f00035325a8d36aa13f30f77df6392a3..e5dc2e4f48a896612de04475bf8703c724aa1863 100644
--- a/nifty5/operators/simple_linear_operators.py
+++ b/nifty5/operators/simple_linear_operators.py
@@ -187,7 +187,7 @@ class GeometryRemover(LinearOperator):
     domain: Domain, tuple of Domain, or DomainTuple:
         the full input domain of the operator.
     space: int, optional
-        The index of the subdomain on which the operator should act. Default is None.
+        The index of the subdomain on which the operator should act.
         If None, it acts on all spaces.
 
     Notes
diff --git a/nifty5/plot.py b/nifty5/plot.py
index e6d869a7145cf48804ab723369d5612f093bfa01..0856a02823347da54b9e37b043a5119711c6aec3 100644
--- a/nifty5/plot.py
+++ b/nifty5/plot.py
@@ -290,8 +290,8 @@ def _plot(f, ax, **kwargs):
     if not isinstance(f[0], Field):
             raise TypeError("incorrect data type")
     dom1 = f[0].domain
-    if (len(dom1)==1 and
-        (isinstance(dom1[0],PowerSpace) or
+    if (len(dom1) == 1 and
+        (isinstance(dom1[0], PowerSpace) or
             (isinstance(dom1[0], (RGSpace, LogRGSpace)) and
              len(dom1[0].shape) == 1))):
         _plot1D(f, ax, **kwargs)