如何将元素追加到numpy数组

问题描述：

我想等效于在Numpy中递归地在python列表中添加元素，如以下代码所示

I want to do the equivalent to adding elements in a python list recursively in Numpy, As in the following code

matrix = open('workfile', 'w')
A = []
for row in matrix:
    A.append(row)

print A

我尝试了以下操作:

matrix = open('workfile', 'w')
A = np.array([])
for row in matrix:
    A = numpy.append(row)

print A

它不返回所需的输出，如列表中所示.

It does not return the desired output, as in the list.

编辑此为示例代码:

mat = scipy.io.loadmat('file.mat')
var1 = mat['data1']
A = np.array([])
for row in var1:
    np.append(A, row)

print A

这只是我想做的最简单的情况，但是循环中有更多的数据处理，我这样写，这样例子很清楚.

This is just the simplest case of what I want to do, but there is more data processing in the loop, I am putting it this way so the example is clear.

答

您需要将数组A传递给Numpy.

You need to pass the array, A, to Numpy.

matrix = open('workfile', 'w')
A = np.array([])
for row in matrix:
    A = numpy.append(A, row)

print A

但是，直接从文件加载可能是一个更好的解决方案.

However, loading from the files directly is probably a nicer solution.