Following functions kept:
```pycon
>>> import inspect
... with_args = []
... with_kwargs = []
... for n in dir(mpmath):
... m = getattr(mpmath, n)
... try:
... s = inspect.signature(m)
... except:
... continue
... if any(_.kind == inspect._ParameterKind.VAR_POSITIONAL for _ in s.parameters.values()):
... for name in s.parameters:
... if s.parameters[name].kind == inspect._ParameterKind.VAR_POSITIONAL and name == 'args':
... with_args.append(n)
... break
... if any(_.kind == inspect._ParameterKind.VAR_KEYWORD for _ in s.parameters.values()):
... with_kwargs.append(n)
... print(with_args)
... print(with_kwargs)
...
['arange', 'ellipe', 'ellippi', 'linspace', 'matrix', 'ones', 'timing', 'zeros']
['multiplicity', 'timing']
```
We need support for multiple signatures in the first case. In the
second - it's impossible to implement these functions without kwargs.
Closes#1056
Sergey B Kirpichev
fb69943530