<p>打印装置在这里让你有点不舒服。在</p>
<p><code>__str__</code>实现(这是Python的<code>print</code>函数调用的)返回表达式的字符串版本。在</p>
<p><code>__repr__</code>实现(在解释器中执行一行时调用)触发计算,从而允许您查看计算结果。在</p>
<pre><code>In [2]: iris = Data(odo(os.path.abspath('./blaze/examples/data/iris.csv'), 'postgresql://localhost::iris'))
In [3]: iris
Out[3]:
sepal_length sepal_width petal_length petal_width species
0 5.1 3.5 1.4 0.2 Iris-setosa
1 4.9 3.0 1.4 0.2 Iris-setosa
2 4.7 3.2 1.3 0.2 Iris-setosa
3 4.6 3.1 1.5 0.2 Iris-setosa
4 5.0 3.6 1.4 0.2 Iris-setosa
5 5.4 3.9 1.7 0.4 Iris-setosa
6 4.6 3.4 1.4 0.3 Iris-setosa
7 5.0 3.4 1.5 0.2 Iris-setosa
8 4.4 2.9 1.4 0.2 Iris-setosa
9 4.9 3.1 1.5 0.1 Iris-setosa
...
In [4]: iris.species.distinct()
Out[4]:
species
0 Iris-versicolor
1 Iris-virginica
2 Iris-setosa
In [8]: print(str(iris.species.distinct()))
distinct(_1.species)
In [9]: print(repr(iris.species.distinct()))
species
0 Iris-versicolor
1 Iris-virginica
2 Iris-setosa
</code></pre>
<p>如果要将结果推送到具体的数据结构中,如<code>pandas.Series</code>,请执行以下操作:</p>
^{pr2}$