Python提取数据

伙计们，我是Python新手。我有个问题。我有一个文本文件，其中包含各种信息。但我只想从特定行开始提取特定列。在下面的数据表中，我只想提取没有标题的“周期/时间”列。请帮忙

4) FOR MULTI-PROCESS EXECUTION, THE ESTIMATED VALUE OF FLOATING POINT OPERATIONS FOR EACH PROCESS
          IS BASED ON AN INITIAL SCHEDULING OF OPERATIONS AND MIGHT NOT REFLECT THE ACTUAL FLOATING 
          POINT OPERATIONS COMPLETED ON EACH PROCESS. OPERATIONS ARE DYNAMICALLY BALANCED DURING EXECUTION, 
          SO THE ACTUAL BALANCE OF OPERATIONS BETWEEN PROCESSES IS EXPECTED TO BE BETTER THAN THE ESTIMATE
          PRINTED HERE.
      (5) THE UPPER LIMIT OF MEMORY THAT CAN BE ALLOCATED BY ABAQUS WILL IN GENERAL DEPEND ON THE VALUE OF
          THE "MEMORY" PARAMETER AND THE AMOUNT OF PHYSICAL MEMORY AVAILABLE ON THE MACHINE. PLEASE SEE
          THE "ABAQUS ANALYSIS USER'S MANUAL" FOR MORE DETAILS. THE ACTUAL USAGE OF MEMORY AND OF DISK
          SPACE FOR SCRATCH DATA WILL DEPEND ON THIS UPPER LIMIT AS WELL AS THE MEMORY REQUIRED TO MINIMIZE
          I/O. IF THE MEMORY UPPER LIMIT IS GREATER THAN THE MEMORY REQUIRED TO MINIMIZE I/O, THEN THE ACTUAL
          MEMORY USAGE WILL BE CLOSE TO THE ESTIMATED "MEMORY TO MINIMIZE I/O" VALUE, AND THE SCRATCH DISK
          USAGE WILL BE CLOSE-TO-ZERO; OTHERWISE, THE ACTUAL MEMORY USED WILL BE CLOSE TO THE PREVIOUSLY
          MENTIONED MEMORY LIMIT, AND THE SCRATCH DISK USAGE WILL BE ROUGHLY PROPORTIONAL TO THE DIFFERENCE
          BETWEEN THE ESTIMATED "MEMORY TO MINIMIZE I/O" AND THE MEMORY UPPER LIMIT. HOWEVER ACCURATE
          ESTIMATE OF THE SCRATCH DISK SPACE IS NOT POSSIBLE.
      (6) USING "*RESTART, WRITE" CAN GENERATE A LARGE AMOUNT OF DATA WRITTEN IN THE WORK DIRECTORY.


                              E I G E N V A L U E    O U T P U T     

 MODE NO      EIGENVALUE              FREQUENCY                GENERALIZED MASS           COMPOSITE MODAL DAMPING
                             (RAD/TIME)   (CYCLES/TIME)     (TOTAL)  (ACOUSTIC FRACTION)


       1      1.13817E+05     337.37         53.694         1.0000        5.48556E-03     0.0000    
       2      1.48191E+05     384.96         61.268         1.0000        5.15017E-03     0.0000    
       3      1.77303E+05     421.07         67.016         1.0000        6.92114E-03     0.0000    
       4      2.43292E+05     493.25         78.503         1.0000        2.69776E-02     0.0000    
       5      2.62266E+05     512.12         81.506         1.0000        4.64713E-03     0.0000    
       6      3.61046E+05     600.87         95.632         1.0000        4.13076E-03     0.0000    
       7      3.96750E+05     629.88         100.25         1.0000        1.50593E-02     0.0000    
       8      4.06070E+05     637.24         101.42         1.0000        1.40587E-02     0.0000    
       9      5.71261E+05     755.82         120.29         1.0000        1.07618E-02     0.0000    
      10      5.90913E+05     768.71         122.34         1.0000        1.11108E-02     0.0000    
      11      6.36854E+05     798.03         127.01         1.0000        4.06691E-03     0.0000    
      12      7.60037E+05     871.80         138.75         1.0000        3.86252E-03     0.0000    
      13      7.70433E+05     877.74         139.70         1.0000        9.25278E-03     0.0000  

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文件的格式是什么，是txt文件吗

你可以利用，一旦你到达了你想要的线，你可以根据列之间的空格去掉红色的线

MODE NO        EIGENVALUE              FREQUENCY                GENERALIZED MASS           COMPOSITE MODAL DAMPING
                             (RAD/TIME)   (CYCLES/TIME)     (TOTAL)  (ACOUSTIC FRACTION)
1             1.13817E+05     337.37         53.694         1.0000        5.48556E-03           0.0000    
2             1.48191E+05     384.96         61.268         1.0000        5.15017E-03           0.0000    

行

1

的列表将是

['1'，'1.13817E+05'，'337.37'，'53.694'，'1.0000'，'5.48556E-03'，'0.0000']

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您需要的元素将是每行的每个列表的@position

3

，

0

是第一个元素

有几种方法可以从Python中的文件中读取数据。一个非常有用的库名为Pandas，它很可能与Python一起安装，如果不是，您可以键入：

pip install pandas

如果删除与列不对应的信息，然后通过以下方式读取文件：

data = pd.read_csv('output_list.txt', sep=" ", header=None)
data.columns = ["Mode NO", "Eigenvalue", "Frequency", "etc."]

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这个答案是从他们解释了这一点和另一种使用熊猫提取信息的技术中提取出来的。

到目前为止，你尝试了什么？请发一些代码。