如何将一组csv文件转换为另一组csv文件（具有不同的文件名和格式）？

Question

我有一些文件，包括以下格式的日终库存数据：

文件名：NYSE\u 20116.txt

<ticker>,<date>,<open>,<high>,<low>,<close>,<vol>
A,20120116,36.15,36.36,35.59,36.19,3327400
AA,20120116,10.73,10.78,10.53,10.64,20457600

如何为每个符号创建文件？ 例如A公司

文件名：A.txt

<ticker>,<date>,<open>,<high>,<low>,<close>,<vol>
A,20120116,36.15,36.36,35.59,36.19,3327400
A,20120117,39.76,40.39,39.7,39.99,4157900

Answer 1

是否要在记录级别拆分第一个文件，然后根据第一个字段的值将每行路由到不同的文件？你知道吗

 # To skip first line, see later
 cat endday.txt | while read line; do
     # Careful with backslashes here - they're not quote signs
     # If supported, use:
     # symbol=$( echo "$line" | cut -f1 -d, )
     symbol=`echo "$line" | cut -f1 -d,`

     # If file is not there, create it with a header
     # if [ ! -r $symbol.txt ]; then
     #    head -n 1 endday.txt > $symbol.txt
     # fi
     echo "$line" >> $symbol.txt
 done

效率不高：Perl或Python会更好。你知道吗

如果一个目录中有多个文件（请注意，您必须自己删除它们，否则它们将被一次又一次地处理……），您可以执行以下操作：

 for file in *.txt; do
    echo "Now processing $file..."
    # A quick and dirty way of ignoring line number 1  - start at line 2.
    tail -n +2 $file | while read line; do
       # Careful with backslashes here - they're not quote signs
       # If supported, use:
       # symbol=$( echo "$line" | cut -f1 -d, )
       symbol=`echo "$line" | cut -f1 -d,`

       # If file is not there, create it with a header
       # if [ ! -r $symbol.txt ]; then
       #    head -n 1 $file > $symbol.csv
       # fi
       # Output file is named .CSV so as not to create new .txt files
       # which this script might find
       echo "$line" >> $symbol.csv
    done
    # Change the name from .txt to .txt.ok, so it won't be found again
    mv $file $file.ok
    # or better move it elsewhere to avoid clogging this directory
    # mv $file /var/data/files/already-processed
 done