Menu
I'm a Linux newbie and have copied a bash script that extracts values from a XML. I can echo the result of a calculation perfectly, but assigning this to a variable doesn't seem to work.
#!/bin/bash
IFS=$'\r\n' result=(`curl -s "http://xxx.xxx.xxx.xxx/smartmeter/modules" | \
xmlstarlet sel -I -t -m "/modules/module" \
-v "cumulative_logs/cumulative_log/period/measurement" -n \
-v "point_logs/point_log/period/measurement" -n | \
sed '/^$/d' `)
# uncomment for debug
echo "${result[0]}"*1000 |bc
gas=$(echo"${result[0]}"*1000 |bc)
echo "${result[0]}"*1000 |bc
Gives me the result I need, but I do not know how to assign it to a variable.
I tried with tick marks:
gas=\`echo"${result[0]}"*1000 |bc\`
And with $(
Can somebody point me in the right direction?
584
Also you need $() to run a command and don't need quotes on the right-hand side of an assignment. Also, shell variables are case sensitive. You can reduce your 2 sed commands to one: sed -e 's/,\|$/: chararray /g' -- that is, replace all commas or end of string with the replacement text.
To store the output of a command in a variable, you can use the shell command substitution feature in the forms below: variable_name=$(command) variable_name=$(command [option ...] arg1 arg2 ...) OR variable_name='command' variable_name='command [option ...]
If the value you assign to a variable includes spaces, they must be in quotation marks when you assign them to the variable. This is because, by default, Bash uses a space as a delimiter. Bash sees the space before “Geek” as an indication that a new command is starting.
If you want to use bc anyway then
you can just use back ticks , why you are using the backslashes? this code works , I just tested.
gas=`echo ${result[0]}*1000 | bc`
Use one space after echo and no space around * operator
150
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With