用bash中的数组元素算术

Question

我正在使用bash并尝试添加从文件创建的数组的所有元素.

while read line; do
    array=($line);
    sum=0
    length=${#array[@]}
    for i in ${array[@]:0:$length}; do
       sum=$[$sum+${array[i]}]   #<--- this doesn't work?
    done
    echo $sum
done < $1

编辑:我应该更清楚为什么我想在for循环中使用数组拆分

输入可能是------> david 34 28 9 12

我想打印--->大卫83

所以我想循环遍历所有元素接受第一个.所以我会用:

length=$[${#array[@]} - 1]
for i in${array[@]:1:$length}

因为这个我不能用:

for i in "${array[@]}"

Answer 1

尝试使用expr添加两个表达式,如:

sum=$(expr "$sum" + "${arr[i]}")

要么

sum=$((sum + arr[i]))


echo "11 13" >test.txt 
echo "12" >>test.txt

while read -a line; do ##read it as array
    sum=0
    for ((i=1; i < ${#line}; i++)); do ##for every number in line
       sum=$(expr "$sum" + "${line[i]}") ## add it to sum
    done
    echo $line[0] $sum ##print sum
done < test.txt
Output
36

OP编辑后:

echo"ABC 11 13"> test.txt echo"DEF 12">> test.txt

while read -a line; do ##read it as array
sum=0
for ((i=1; i < $((${#line[@]})); i++)); do ##for every number in line
   sum=$(expr "$sum" + "${line[i]}") ## add it to sum
   if [[ $i -eq $((${#line[@]}-1)) ]]
   then
       echo "${line[0]} $sum" ##print sum
       sum=0
   fi
done
done < test.txt
Output:
ABC 24
DEF 12