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udfPreprocess/cleaning,py

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+import pandas as pd
+import numpy as np
+import string  
+import nltk 
+import spacy
+import en_core_web_sm
+import re
+import streamlit as st
+
+from haystack.nodes import PreProcessor
+
+'''basic cleaning - suitable for transformer models'''
+def basic(s):
+    """
+    :param s: string to be processed
+    :return: processed string: see comments in the source code for more info
+    """
+    # Text Lowercase
+    #s = s.lower() 
+    # Remove punctuation
+    #translator = str.maketrans(' ', ' ', string.punctuation) 
+    #s = s.translate(translator)
+    # Remove URLs
+    s = re.sub(r'^https?:\/\/.*[\r\n]*', ' ', s, flags=re.MULTILINE)
+    s = re.sub(r"http\S+", " ", s)
+    # Remove new line characters
+    #s = re.sub('\n', ' ', s) 
+  
+    # Remove distracting single quotes
+    #s = re.sub("\'", " ", s) 
+    # Remove all remaining numbers and non alphanumeric characters
+    #s = re.sub(r'\d+', ' ', s) 
+    #s = re.sub(r'\W+', ' ', s)
+
+    # define custom words to replace:
+    #s = re.sub(r'strengthenedstakeholder', 'strengthened stakeholder', s)
+    
+    return s.strip()
+
+
+def preprocessingForSDG(document):
+
+    """
+    takes in haystack document object and splits it into paragraphs and applies simple cleaning.
+    Returns cleaned list of haystack document objects. One paragraph per object. Also returns pandas df and 
+    list that contains all text joined together.
+    """    
+
+    preprocessor = PreProcessor(
+        clean_empty_lines=True,
+        clean_whitespace=True,
+        clean_header_footer=True,
+        split_by="word",
+        split_length=100,
+        split_respect_sentence_boundary=True,
+        split_overlap=4
+    )
+    for i in document:
+        docs_processed = preprocessor.process([i])
+        for item in docs_processed:
+            item.content = basic(item.content)
+
+    st.write("your document has been splitted to", len(docs_processed), "paragraphs")
+    
+    # create dataframe of text and list of all text
+    df = pd.DataFrame(docs_processed)
+    all_text = " ".join(df.content.to_list())
+    par_list = df.content.to_list()
+
+    return docs_processed, df, all_text, par_list
+
+def preprocessing(document):
+
+    """
+    takes in haystack document object and splits it into paragraphs and applies simple cleaning.
+    Returns cleaned list of haystack document objects. One paragraph per object. Also returns pandas df and 
+    list that contains all text joined together.
+    """    
+
+    preprocessor = PreProcessor(
+        clean_empty_lines=True,
+        clean_whitespace=True,
+        clean_header_footer=True,
+        split_by="sentence",
+        split_length=3,
+        split_respect_sentence_boundary=False,
+        split_overlap=1
+    )
+    for i in document:
+        docs_processed = preprocessor.process([i])
+        for item in docs_processed:
+            item.content = basic(item.content)
+
+    st.write("your document has been splitted to", len(docs_processed), "paragraphs")
+    
+    # create dataframe of text and list of all text
+    df = pd.DataFrame(docs_processed)
+    all_text = " ".join(df.content.to_list())
+    par_list = df.content.to_list()
+
+    return docs_processed, df, all_text, par_list
+
+'''processing with spacy - suitable for models such as tf-idf, word2vec'''
+def spacy_clean(alpha:str, use_nlp:bool = True) -> str:
+
+    """
+    Clean and tokenise a string using Spacy. Keeps only alphabetic characters, removes stopwords and
+    filters out all but proper nouns, nounts, verbs and adjectives.
+    Parameters
+    ----------
+    alpha : str
+            The input string.
+    use_nlp : bool, default False
+            Indicates whether Spacy needs to use NLP. Enable this when using this function on its own.
+            Should be set to False if used inside nlp.pipeline   
+     Returns
+    -------
+    ' '.join(beta) : a concatenated list of lemmatised tokens, i.e. a processed string
+    Notes
+    -----
+    Fails if alpha is an NA value. Performance decreases as len(alpha) gets large.
+    Use together with nlp.pipeline for batch processing.
+    """
+
+    nlp = spacy.load("en_core_web_sm", disable=["parser", "ner", "textcat"])
+
+    if use_nlp:
+
+        alpha = nlp(alpha)
+
+        
+
+    beta = []
+
+    for tok in alpha:
+
+        if all([tok.is_alpha, not tok.is_stop, tok.pos_ in ['PROPN', 'NOUN', 'VERB', 'ADJ']]):
+
+            beta.append(tok.lemma_)
+
+            
+    text = ' '.join(beta)
+    text = text.lower()
+    return text