使用BASH实用程序提取文本数据

Question

我有非平凡的任务，可以从大型CSV日志中提取一些相关数据，看起来像

Frame #,Residue,Internal,van der Waals,Electrostatic,Polar Solvation,Non-Polar Solv.,TOTAL
1,1,119.745,0.356,-132.009,-95.618,1.7886312,-105.7373688
1,2,106.093,-3.835,-182.473,40.582,0.7132608,-38.9197392
1,3,21.228,-1.744,-38.026,-7.707,1.1189664,-25.1300336
1,4,-5.717,-4.721,-30.38,-4.839,0.406512,-45.250488
1,5,70.846,-4.127,-53.317,-2.534,0.7808472,11.6488472
...
2,1,119.745,0.356,-132.009,-95.618,1.7886312,-105.7373688
2,2,106.093,-3.835,-182.473,40.582,0.7132608,-38.9197392
2,3,21.228,-1.744,-38.026,-7.707,1.1189664,-25.1300336
2,4,-5.717,-4.721,-30.38,-4.839,0.406512,-45.250488
2,5,70.846,-4.127,-53.317,-2.534,0.7808472,11.6488472
...
n,1,119.745,0.356,-132.009,-95.618,1.7886312,-105.7373688
n,2,106.093,-3.835,-182.473,40.582,0.7132608,-38.9197392
n,3,21.228,-1.744,-38.026,-7.707,1.1189664,-25.1300336
n,4,-5.717,-4.721,-30.38,-4.839,0.406512,-45.250488
n,5,70.846,-4.127,-53.317,-2.534,0.7808472,11.6488472

在这里，我想根据第1列（#frame编号）从第二列（#isidue）中选择一个值（#isidue），然后在其最后一列（#total Energy）的" #snapshot Number列的函数"（#Total Energy）（#total Energy）（#frame编号）中选择一个值。换句话说，我需要1）根据第二列首先对所有数据进行排序）：即选择每个字符串，其中第二列中的数字等于指定值（即n = 27）

#Frame, #Residue
1,27, ... , # last column value which is interested for me!
2,27, ... , # last column value which is interested for me!
3,27, ... , # last column value which is interested for me!
3,27, ... , # last column value which is interested for me!

而不是提取其最后一列的相应值，因此恢复日志将具有3列：

#Frame, #Residue, # Total energy
1,27, # last column value which is interested for me!
2,27, # last column value which is interested for me!
3,27, # last column value which is interested for me!
3,27, # last column value which is interested for me!

将感谢使用AWK和SED！

实现的任何意识

谢谢！

gleb

Answer 1

要在第二列中使用27提取行，您可以使用grep：

  grep '^[^,]+,27,' input.csv
        | |   |
beginning |   |
    not comma |
              repeated

仅输出第一，第二和第8列，请使用cut：

grep '^[^,]+,27' input.csv | cut -d, -f1,2,8
                                   |   |
                             delimiter |
                                      fields

要按第二列对文件进行排序，您可以使用sort：

sort -t, -nk2,2 input.csv
      |   | |
delimiter | |
    numeric |
    sort    by only the second field

Answer 2

这是一个尴尬解决方案：

awk -v n=27 'BEGIN { OFS = FS = "," } $2 == n { print $1, $2, $NF }' input.csv

• -v n=27-首先分配尴尬变量n值27
• BEGIN { OFS = FS = "," }-开始在尴尬开始解析任何数据之前运行。在这里，我们将FS（场分离器）和OFS（输出场分隔符）设置为"，以便将输入线和输出线通过逗号分开/分离。
• $2 == n { print $1, $2, $NF }-对于任何记录（线），第二个字段（$ 2）等于n，输出第一个，第二和最后一个字段。

在 m 匹配之后停止：

awk -v n=27 -v m=3 'BEGIN { OFS = FS = "," } $2 == n { print $1, $2, $NF; if (++count == m) exit}' input.csv