I'm struggling to figure out how to get dask delayed to work on a particular workflow that involves creating a dictionary.
The idea here is that func1, func2, func3 can run independently of each other at the same time, and I want the results of those functions to be the values in a new dictionary z.
from dask.delayed import delayed
x1 = {'a': 1, 'b': 2, 'c': 3}
x2 = {'a': 4, 'b': 5, 'c': 6}
@delayed
def func1(d1, d2):
return d1['a'] + d2['a']
@delayed
def func2(d1, d2):
return d1['b'] - d2['b']
@delayed
def func3(d1, d2):
return d1['c'] * d2['c']
z = {}
z['val1'] = func1(x1, x2)
z['val2'] = func2(x1, x2)
z['val3'] = func3(x1, x2)
When I run the following, I get an error:
>>> result_dict = z.compute()
AttributeError: 'dict' object has no attribute 'compute'
When I run the following, it succeeds however the result is a tuple and not a dictionary.
>>> result_dict = dask.compute(z)
({'val1': 5, 'val2': -3, 'val3': 18},)
How do I compute the results so it returns a dictionary? Am I doing this right?
As you saw, dask.compute returns a tuple of results
>>> dask.compute(z)
({'val1': 5, 'val2': -3, 'val3': 18},)
This is because you can give it many arguments and it results a result for each argument
>>> result_dict = dask.compute(x, y, z)
(..., ..., ...)
You don't care about this, you only want the first element. You can get the first element of a tuple in Python using the getitem [...] syntax.
>>> dask.compute(z)[0]
{'val1': 5, 'val2': -3, 'val3': 18}