I have a list of functions. Each function may return either a float or a list of 2 floats. I need to build a flat list of results using a list comprhension. For efficiency reasons, I need to build the results using one single iteration. For the same reason, the for loop is not an option (this is my belief... Is this correct?).
Input:
funcs=[[function_1, arguments_function_1],[function_2,arguments_function_2]...[function_n, arguments_function_n]
where function_j is a previously defined function. arguments_function_j is the list of arguments for funtion_j.
Tentative call:
results=[f[0](f[1]) for f in funcs]
The above call is syntactically correct but does not return the results in the format I need. In facts, assuming that the forth function returns a list, the final result would be
[1,2,3,[4,5],6] instead of [1,2,3,4,5,6] as I need
I tried the following:
results=[f[0](f[1]) if type(f[0](f[1]))==float\
else f[0](f[1])[0],f[0](f[1])[1]\
for f in funcs]
But the f[0](f[1])[0],f[0](f[1])[1] part is not syntactically correct. It should be placed between bracktes but then it would not solve the problem.
Any hint? Thanks in advance
you just need to chain your values so instead of
results=[f[0](f[1]) for f in funcs]
just do
import itertools
result = list(itertools.chain.from_iterable(f[0](f[1]) for f in funcs))
(that will flatten your list of results, wrapped in list to force iteration)