Question

我有一些pdf格式的研究论文，我只想从论文中提取介绍/背景等信息。另外，我只能使用python。有人可以帮忙吗？

Answer 1

几周前，我在这里得到了类似的帮助。使用PDF文件可能很容易，也可能非常困难，并且PDF文件种类繁多。话虽如此，您应该考虑将所有PDF文件转换为文本文件。尝试下面的代码示例。

首先，将PDF转换为文本。

from io import StringIO
from pdfminer.pdfinterp import PDFResourceManager, PDFPageInterpreter
from pdfminer.converter import TextConverter
from pdfminer.layout import LAParams
from pdfminer.pdfpage import PDFPage
import os
import sys, getopt

#converts pdf, returns its text content as a string
def convert(fname, pages=None):
    if not pages:
        pagenums = set()
    else:
        pagenums = set(pages)

    output = io.StringIO()
    manager = PDFResourceManager()
    converter = TextConverter(manager, output, laparams=LAParams())
    interpreter = PDFPageInterpreter(manager, converter)

    infile = open(fname, 'rb')
    for page in PDFPage.get_pages(infile, pagenums):
        interpreter.process_page(page)
    infile.close()
    converter.close()
    text = output.getvalue()
    output.close
    return text 

#converts all pdfs in directory pdfDir, saves all resulting txt files to txtdir
def convertMultiple(pdfDir, txtDir):
    if pdfDir == "": pdfDir = os.getcwd() + "\\" #if no pdfDir passed in 
    for pdf in os.listdir(pdfDir): #iterate through pdfs in pdf directory
        fileExtension = pdf.split(".")[-1]
        if fileExtension == "pdf":
            pdfFilename = pdfDir + pdf 
            text = convert(pdfFilename) #get string of text content of pdf
            textFilename = txtDir + pdf + ".txt"
            textFile = open(textFilename, "w") #make text file
            textFile.write(text) #write text to text file

# set paths accordingly:
pdfDir = "C:/your_path_here/PDF_in/"
txtDir = "C:/your_path_here/TEXT_out/"
convertMultiple(pdfDir, txtDir)

第二，在开始标记（“纽约州房地产法”）和结束标记（“财产的共同要素”）之间查找所有文本。

# Loop through all TEXT files in a folder
# Pull out all text between two anchors: "New York State Real Property Law" & "common elements of the property."
import re
import os
myRegex=re.compile("New York State Real Property Law.*?common elements of the property\.",re.DOTALL)
for foldername,subfolders,files in os.walk(r"C:/your_path_here/text_files/"):
    for file in files:
        print(file)
        object=open(os.path.join(foldername,file))
        Text=object.read()
        for subText in myRegex.findall(Text):
            print(subText)

object.close()

也许您可以完成所有工作而无需将PDF转换为文本文件，但是我还没有找到任何方法。

从PDF文档中提取特定段

1 个答案: