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    Pythonlangchain-classicevaluationqaeval_chain
    Moduleā—Since v1.0

    eval_chain

    Attributes

    Classes

    View source on GitHub
    attribute
    CONTEXT_PROMPT
    attribute
    COT_PROMPT
    attribute
    PROMPT
    attribute
    RUN_KEY: str
    class
    LLMEvalChain
    class
    StringEvaluator
    class
    QAEvalChain
    class
    ContextQAEvalChain
    class
    CotQAEvalChain
    deprecatedclass
    LLMChain

    LLM Chains for evaluating question answering.

    A base class for evaluators that use an LLM.

    String evaluator interface.

    Grade, tag, or otherwise evaluate predictions relative to their inputs and/or reference labels.

    LLM Chain for evaluating question answering.

    LLM Chain for evaluating QA w/o GT based on context.

    LLM Chain for evaluating QA using chain of thought reasoning.

    Chain to run queries against LLMs.

    This class is deprecated. See below for an example implementation using LangChain runnables:

    from langchain_core.output_parsers import StrOutputParser
    from langchain_core.prompts import PromptTemplate
    from langchain_openai import OpenAI
    
    prompt_template = "Tell me a {adjective} joke"
    prompt = PromptTemplate(input_variables=["adjective"], template=prompt_template)
    model = OpenAI()
    chain = prompt | model | StrOutputParser()
    
    chain.invoke("your adjective here")