RapidMiner：用另一个值替换值 column/attribute

Question

我的问题是，如果我在一行中有一个缺失值，我想用该行中的另一个值替换这个值。例如我想用适当的 "Belegnummer"

替换缺失值

Answer 1

一般来说，有一个名为 Replace Missing Values 的运算符，其功能与名称所暗示的完全相同。

在您的特殊情况下，您想要访问另一个属性（列）的值，因此 Generate Attributes 运算符提供了一个非常强大的表达式构建器，您可以在其中声明一个 If-这种形式的陈述 if(a1==MISSING_NUMERIC, a2,a1)

请参阅上面的屏幕截图以获取示例或将进程 XML 复制并粘贴到您的 RapidMiner 进程 window。

<?xml version="1.0" encoding="UTF-8"?><process version="9.0.000-BETA">
<context>
<input/>
<output/>
<macros/>
</context>
<operator activated="true" class="process" compatibility="9.0.000-BETA" expanded="true" name="Process">
<process expanded="true">
  <operator activated="true" class="subprocess" compatibility="9.0.000-BETA" expanded="true" height="82" name="Subprocess" width="90" x="112" y="34">
    <process expanded="true">
      <operator activated="true" class="retrieve" compatibility="9.0.000-BETA" expanded="true" height="68" name="Retrieve Iris" width="90" x="45" y="34">
        <parameter key="repository_entry" value="//Samples/data/Iris"/>
      </operator>
      <operator activated="true" class="declare_missing_value" compatibility="9.0.000-BETA" expanded="true" height="82" name="Declare Missing Value" width="90" x="179" y="34">
        <parameter key="attribute_filter_type" value="single"/>
        <parameter key="attribute" value="a1"/>
        <parameter key="mode" value="expression"/>
        <parameter key="expression_value" value="a1 &lt;5"/>
      </operator>
      <operator activated="true" class="select_attributes" compatibility="9.0.000-BETA" expanded="true" height="82" name="Select Attributes" width="90" x="380" y="34">
        <parameter key="attribute_filter_type" value="subset"/>
        <parameter key="attributes" value="a2|a1"/>
      </operator>
      <connect from_op="Retrieve Iris" from_port="output" to_op="Declare Missing Value" to_port="example set input"/>
      <connect from_op="Declare Missing Value" from_port="example set output" to_op="Select Attributes" to_port="example set input"/>
      <connect from_op="Select Attributes" from_port="example set output" to_port="out 1"/>
      <portSpacing port="source_in 1" spacing="0"/>
      <portSpacing port="sink_out 1" spacing="0"/>
      <portSpacing port="sink_out 2" spacing="0"/>
    </process>
  </operator>
  <operator activated="true" class="generate_attributes" compatibility="9.0.000-BETA" expanded="true" height="82" name="Generate Attributes" width="90" x="447" y="34">
    <list key="function_descriptions">
      <parameter key="a1_new" value="if(a1==MISSING_NUMERIC, a2,a1)"/>
    </list>
  </operator>
  <connect from_op="Subprocess" from_port="out 1" to_op="Generate Attributes" to_port="example set input"/>
  <connect from_op="Generate Attributes" from_port="example set output" to_port="result 1"/>
  <portSpacing port="source_input 1" spacing="0"/>
  <portSpacing port="sink_result 1" spacing="0"/>
  <portSpacing port="sink_result 2" spacing="0"/>
  <description align="center" color="yellow" colored="false" height="181" resized="true" width="529" x="275" y="126">With the expression parser more complex statements can be defined. In this case:&lt;br&gt;if(a1==MISSING_NUMERIC, a2,a1)&lt;br/&gt;&lt;br/&gt;meaning that if the value of attribute a1 is missing, it will be replaced by the value of a2 otherwise the value of a1 is kept.&lt;br/&gt;&lt;br/&gt;Instead of creating a new attribute the old one can also be overwritten&lt;br/&gt;&lt;br&gt;</description>
</process>
</operator>
</process>

RapidMiner：用另一个值替换值 column/attribute

RapidMiner: Replace Value with a value from another column/attribute

replace

missing-data

rapidminer