python - reshape dask 数组(从 dask 数据框列获得)

Question

我是 dask 新手，正在尝试弄清楚如何 reshape 从 dask 数据帧的单列获得的 dask 数组，但遇到了错误。想知道是否有人知道修复方法(无需强制计算)？谢谢!

示例:

import pandas as pd
import numpy as np
from dask import dataframe as dd, array as da
df = pd.DataFrame({'x': [1, 2, 3], 'y': [4, 5, 6]})
ddf = dd.from_pandas(df, npartitions=2)

# This does not work - error ValueError: cannot convert float NaN to integer
ddf['x'].values.reshape([-1,1])

# this works, but requires a compute
ddf['x'].values.compute().reshape([-1,1])

# this works, if the dask array is created directly from a np array
ar = np.array([1, 2, 3])
dar = da.from_array(ar, chunks=2)
dar.reshape([-1,1])

Answer 1

另外:

ddf['x'].to_dask_array(lengths=True).reshape([-1,1])