Copy of array by index value fails Post: 303012758

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Top Forums Shell Programming and Scripting Copy of array by index value fails Post 303012758 by LMHmedchem on Thursday 8th of February 2018 12:51:51 PM

02-08-2018

Registered User

Copy of array by index value fails

Hello,

I have a complicated situational find and replace that I wrote in bash because I didn't know how to do everything in awk. The code works but is very slow, as expected.

To create my modified file, I am looping through an array that was populated earlier and making some replacements at stored positions.

Code:

# loop through stored record
for ((j=0; j <= $i ; j++)) ; do
   # for the first line, add the new firstline value
   if [[ $j == "0" ]]; then
      echo $new_firstline >> $output_file
   # when the replace line is found, use the substitute value
   elif [[ $j == "$replace_line" ]]; then
      echo $new_name >> $output_file
   # output all other lines as normal
   else
      echo ${line_array[$j]} >> $output_file
   fi
done

This is obviously going to be very slow because of all the file operations. My intent was to write the new file to an array and then print the array at the end.

Code:

# store the record
while read line 
do
   # store line in array
   line_array[$i]="$line"
   # increment counter
   i=$((i+1))
done < $input_file

...
other code to test some things and make new variables
...

# declare an array to store the output
declare -a modified_file
# loop through stored file
for ((j=0; j <= $i ; j++)) ; do
   # for the first line, add the new firstline value to the output array
   if [[ $j == "0" ]]; then
      modified_file=("${modified_file[@]}" "$new_firstline")
   # when the replace line is found, add the substitute value to the output array
   elif [[ $j == "$replace_line" ]]; then
      modified_file=("${modified_file[@]}" "$new_name")
   # output all other lines as normal
   else
      modified_file=("${modified_file[@]}" "${line_array[$j]}")
   fi
done

# print the modified file array to the output file
echo ${modified_file[@]} >> $output_file

This seems like it should be right but all I get when I print modified_file[@] is a series of integers, like it is printing the array index.

What am I doing wrong here? Let me know if I didn't provide enough information.

Thanks,

LMHmedchem

Last edited by LMHmedchem; 02-08-2018 at 01:58 PM..

LMHmedchem

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NAME

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RESTRICTED SHELL

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SEE ALSO

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