Python 将列表转换为 numpy 数组
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Converting list to numpy array
提问by Priya Narayanan
I have managed to load images in a folder using the command line sklearn: load_sample_images()
我设法使用命令行 sklearn 在文件夹中加载图像： load_sample_images()
I would now like to convert it to a numpy.ndarrayformat with float32datatype
我现在想将其转换为numpy.ndarray具有float32数据类型的格式
I was able to convert it to np.ndarrayusing : np.array(X), however np.array(X, dtype=np.float32)and np.asarray(X).astype('float32')give me the error:
我能够将其转换为np.ndarrayusing : np.array(X)，但是np.array(X, dtype=np.float32)并np.asarray(X).astype('float32')给我错误：
ValueError: setting an array element with a sequence.
ValueError: setting an array element with a sequence.
Is there a way to work around this?
有没有办法解决这个问题？
from sklearn_theano.datasets import load_sample_images
import numpy as np
kinect_images = load_sample_images()
X = kinect_images.images
X_new = np.array(X) # works
X_new = np.array(X[1], dtype=np.float32) # works
X_new = np.array(X, dtype=np.float32) # does not work
回答by Thom Ives
If you have a list of lists, you only needed to use ...
如果你有一个列表列表，你只需要使用 ...
import numpy as np
...
npa = np.asarray(someListOfLists, dtype=np.float32)
per this LINKin the scipy / numpy documentation. You just needed to define dtype inside the call to asarray.
根据scipy / numpy 文档中的此链接。您只需要在对 asarray 的调用中定义 dtype。
