具有特定域的橙色数据 Table

Question

我正在尝试从 csv-file 创建橙色数据 Table。为实现这一目标，我目前正在尝试使用以下步骤来做到这一点：

创建目标域
正在读取文件到临时数据table
使用临时 table 中的数据创建新数据 table 和目标域

将 csv 更改为具有三行 header (https://docs.orange.biolab.si/3/data-mining-library/reference/data.io.html) 的 tab-file 不是一个选项。

将此过程转换为代码时，我得到以下信息：

  from Orange.data import Domain, DiscreteVariable, ContinuousVariable, Table

    # Creating specific domain. Two attributes and a Class variable used as target
    target_domain = Domain([ContinuousVariable.make("Attribute 1"),ContinuousVariable.make("Attribute 2")],DiscreteVariable.make("Class"))
    print('Target domain:',target_domain) 
    # Target domain: [Attribute 1, Attribute 2 | Class]

    # Reading in the file
    test_data = Table.from_file('../data/knn_trainingset_example.csv')
    print('Domain from file:',test_data.domain)
    # Domain from file: [Attribute 1, Attribute 2, Class]

    # Using specific domain with test_data
    final_data = Table.from_table(target_domain,test_data)

    print('Domain:',final_data.domain)
    print('Data:')
    print(final_data)
    # Domain: [Attribute 1, Attribute 2 | Class]
    # Data:
    # [[0.800, 6.300 | ?],
    #  [1.400, 8.100 | ?],
    #  [2.100, 7.400 | ?],
    #  [2.600, 14.300 | ?],
    #  [6.800, 12.600 | ?],
    #  [8.800, 9.800 | ?],
    # ...

正如您从最终打印语句中看到的那样，class 变量是未知的 (?) 而不是预期的 class（+ 或 -）。

有人可以explain/solve这种行为吗？提供一种 better/different 方法来创建具有特定域的数据 Table?

Answer 1

好的，谢谢！如参考资料 (https://docs.orange.biolab.si/3/data-mining-library/reference/data.variable.html#discrete-variables) 中所述，您必须提供可能的值。因此，将它们作为元组提供就可以了。为了将来参考，我将调整后的代码放在下面。

from Orange.data import Domain, DiscreteVariable, ContinuousVariable, Table

# Creating specific domain. Two attributes and a Class variable used as target
target_domain = Domain([ContinuousVariable.make("Attribute 1"),ContinuousVariable.make("Attribute 2")],DiscreteVariable.make("Class",values=('+','-')))

print('Target domain:',target_domain)
# Target domain: [Attribute 1, Attribute 2 | Class]

# Reading in the file
test_data = Table.from_file('../data/knn_trainingset_example.csv')

print('Domain from file:',test_data.domain)
# Domain from file: [Attribute 1, Attribute 2, Class]

print('Data:')
print(test_data)
# [[0.800, 6.300 | −],
#  [1.400, 8.100 | −],
#  [2.100, 7.400 | −],
#  [2.600, 14.300 | +],
#  [6.800, 12.600 | −],
#  [8.800, 9.800 | +],
# ...

# Using specific domain with test_data
final_data = Table.from_table(target_domain,test_data)

print('Domain:',final_data.domain)
# Domain: [Attribute 1, Attribute 2 | Class]

print('Data:')    
# Data:
# [[0.800, 6.300 | −],
#  [1.400, 8.100 | −],
#  [2.100, 7.400 | −],
#  [2.600, 14.300 | +],
#  [6.800, 12.600 | −],
#  [8.800, 9.800 | +],
# ...

具有特定域的橙色数据 Table

Orange Data Table with specific domain

csv

python-3.x

orange