Is there an equivalent to R's do.call in python?
do.call(what = 'sum', args = list(1:10)) #[1] 55
do.call(what = 'mean', args = list(1:10)) #[1] 5.5
?do.call
# Description
# do.call constructs and executes a function call from a name or a function and a list of arguments to be passed to it.
There is no built-in for this, but it is easy enough to construct an equivalent.
You can look up any object from the built-ins namespace using the __builtin__ (Python 2) or builtins (Python 3) modules then apply arbitrary arguments to that with *args and **kwargs syntax:
try:
# Python 2
import __builtin__ as builtins
except ImportError:
# Python 3
import builtins
def do_call(what, *args, **kwargs):
return getattr(builtins, what)(*args, **kwargs)
do_call('sum', range(1, 11))
Generally speaking, we don't do this in Python. If you must translate strings into function objects, it is generally preferred to build a custom dictionary:
functions = {
'sum': sum,
'mean': lambda v: sum(v) / len(v),
}
then look up functions from that dictionary instead:
functions['sum'](range(1, 11))
This lets you strictly control what names are available to dynamic code, preventing a user from making a nuisance of themselves by calling built-ins for their destructive or disruptive effects.
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