如何在Shell脚本中将循环的输出值存储在数组中？

Question

In shell scripting, I have a loop with an if condition inside a for loop.

for ((init; condition; increment))
do
    if ((condition)) then
        printf ...
    fi
done

printf statement prints the values on the output. However, I want to store these values in an array to use inside another loop. How do I do this?

Answer 1

You initialize an array before for loop and inside for loop just keep appending to array.

Code skeleton:

# initializing an array
arr=()
for ((i=0; i<=5; i++ )) do if ((...)) then arr+=($i); printf .... fi done

• arr=() creates a new array
• arr+=($i) appends/adds an element into array arr

Answer 2

Here's the solution:

#!/bin/bash

data=() #declare an array outside the scope of loop
idx=0   #initialize a counter to zero
for i in {53..99} #some random number range
do
    data[idx]=`printf "number=%s\n" $i` #store data in array
    idx=$((idx+1)) #increment the counter
done
echo ${data[*]} #your result

What code does

• creates and empty array
• creates an index-counter for array
• stores result of output printf command in array at corresponding index (the backquote tells interpreter to do that)