如何使用需要另一个dask任务结果作为关键字参数的函数构建自定义dask图形?
dask文档和一些stackoverflow问题建议使用“partial”、“toolz”或“dask.compatibility.apply”。所有这些解决方案都适用于静态关键字参数。根据在自定义Dask图中包含关键字参数(kwargs)和阅读源代码和调试器的理解,dask.compatibility.apply可能能够处理作为dask计算结果的关键字参数。然而,我似乎无法得到正确的语法,也找不到其他答案。
下面的示例展示了一个相对简单的应用程序,使用dask计算的关键字值来使用dask.compatibility.apply。Dask成功地传递了计算出的args 'a'和'b'的值,以及静态关键字值'other'。然而,它将字符串'c'传递给函数,而不是替换成其计算出的值。
输出如下:
dask文档和一些stackoverflow问题建议使用“partial”、“toolz”或“dask.compatibility.apply”。所有这些解决方案都适用于静态关键字参数。根据在自定义Dask图中包含关键字参数(kwargs)和阅读源代码和调试器的理解,dask.compatibility.apply可能能够处理作为dask计算结果的关键字参数。然而,我似乎无法得到正确的语法,也找不到其他答案。
下面的示例展示了一个相对简单的应用程序,使用dask计算的关键字值来使用dask.compatibility.apply。Dask成功地传递了计算出的args 'a'和'b'的值,以及静态关键字值'other'。然而,它将字符串'c'传递给函数,而不是替换成其计算出的值。
import dask
from dask.compatibility import apply
def custom_func(a, b, other=None, c=None):
print(a, b, other, c)
return a * b / c / other
dsk = {
'a': (sum, (1, 1)),
'b': (sum, (2, 2)),
'c': (sum, (3, 3)),
'd': (apply, custom_func, ['a', 'b'], {'c': 'c', 'other': 2})
}
dask.visualize(dsk, filename='graph.png')
for key in sorted(dsk):
print(key)
print(dask.get(dsk, key))
print('\n')
输出如下:
a
2
b
4
c
6
d
2 4 2 c
Traceback (most recent call last):
File "dask_kwarg.py", line 20, in <module>
print(dask.get(dsk, key))
File "/Users/holmgren/miniconda3/envs/pvlib36/lib/python3.6/site-packages/dask/local.py", line 562, in get_sync
return get_async(apply_sync, 1, dsk, keys, **kwargs)
File "/Users/holmgren/miniconda3/envs/pvlib36/lib/python3.6/site-packages/dask/local.py", line 529, in get_async
fire_task()
File "/Users/holmgren/miniconda3/envs/pvlib36/lib/python3.6/site-packages/dask/local.py", line 504, in fire_task
callback=queue.put)
File "/Users/holmgren/miniconda3/envs/pvlib36/lib/python3.6/site-packages/dask/local.py", line 551, in apply_sync
res = func(*args, **kwds)
File "/Users/holmgren/miniconda3/envs/pvlib36/lib/python3.6/site-packages/dask/local.py", line 295, in execute_task
result = pack_exception(e, dumps)
File "/Users/holmgren/miniconda3/envs/pvlib36/lib/python3.6/site-packages/dask/local.py", line 290, in execute_task
result = _execute_task(task, data)
File "/Users/holmgren/miniconda3/envs/pvlib36/lib/python3.6/site-packages/dask/local.py", line 271, in _execute_task
return func(*args2)
File "/Users/holmgren/miniconda3/envs/pvlib36/lib/python3.6/site-packages/dask/compatibility.py", line 50, in apply
return func(*args, **kwargs)
File "dask_kwarg.py", line 7, in custom_func
return a * b / c / other
TypeError: unsupported operand type(s) for /: 'int' and 'str'