(standard_in) 1: syntax error on script that should work - bash

Question

I've downloaded a script from github, which seems to work, but I'm getting the error when running.
https://github.com/chentda/curl-average-timings
The script calculates the average loading time from a URL
#!/bin/bash
#This is a simple bash script to get the averages of various website response timings using cURL
#Formatted cURL output that contains the various response timings separated by '-'
curl_format="%{time_namelookup}-%{time_connect}-%{time_appconnect}-%{time_pretransfer}-%{time_redirect}-%{time_starttransfer}-%{time_total}"
#Website you want to send the request to
URL="https://www.google.com/"
#How many requests you want to hit website with to get averages
iterations=5
decimal_rounding=5
#Initialising total variables for the various timings
total_time_namelookup="0"
total_time_connect="0"
total_time_appconnect="0"
total_time_pretransfer="0"
total_time_redirect="0"
total_time_starttransfer="0"
total_time_total="0"
for i in `seq 1 $iterations`;
do
response=$(curl -o /dev/null -s -w $curl_format $URL)
#Splits response string by the delimiter of "-"
response_times=($(echo "$response" | tr "-" "\n"))
#Assigning each type of response time to a variable
time_namelookup=${response_times[0]}
time_connect=${response_times[1]}
time_appconnect=${response_times[2]}
time_pretransfer=${response_times[3]}
time_redirect=${response_times[4]}
time_starttransfer=${response_times[5]}
time_total=${response_times[6]}
#Adding variables assigned above in loop to the respective total variables that are set at start of script
total_time_namelookup=$(echo "$total_time_namelookup + $time_namelookup" | bc)
total_time_connect=$(echo "$total_time_connect + $time_connect" | bc)
total_time_appconnect=$(echo "$total_time_appconnect + $time_appconnect" | bc)
total_time_pretransfer=$(echo "$total_time_pretransfer + $time_pretransfer" | bc)
total_time_redirect=$(echo "$total_time_redirect + $time_redirect" | bc)
total_time_starttransfer=$(echo "$total_time_starttransfer + $time_starttransfer" | bc)
total_time_total=$(echo "$total_time_total + $time_total" | bc)
done
#Calculating the average for each type of response time
average_time_namelookup=$(echo "scale=$decimal_rounding; $total_time_namelookup / $iterations" | bc)
average_time_connect=$(echo "scale=$decimal_rounding; $total_time_connect / $iterations" | bc)
average_time_appconnect=$(echo "scale=$decimal_rounding; $total_time_appconnect / $iterations" | bc)
average_time_pretransfer=$(echo "scale=$decimal_rounding; $total_time_pretransfer / $iterations" | bc)
average_time_redirect=$(echo "scale=$decimal_rounding; $total_time_redirect / $iterations" | bc)
average_time_starttransfer=$(echo "scale=$decimal_rounding; $total_time_starttransfer / $iterations" | bc)
average_time_total=$(echo "scale=$decimal_rounding; $total_time_total / $iterations" | bc)
echo "Averages of response timings:"
echo ""
echo " time_namelookup: $average_time_namelookup"
echo " time_connect: $average_time_connect"
echo " time_appconnect: $average_time_appconnect"
echo " time_pretransfer: $average_time_pretransfer"
echo " time_redirect: $average_time_redirect"
echo "time_starttransfer: $average_time_starttransfer"
echo " --------"
echo " time_total: $average_time_total"
After a few debuggin, I can see that the problem is on this line, when uses bc to sum results
total_time_namelookup=$(echo "$total_time_namelookup + $time_namelookup" | bc)
But it throws
(standard_in) 1: syntax error
But I can't figure what I'm doing wrong.
I'm on ubuntu running from the terminal with sh

Answer 1

Your numeric values contains a locale specific decimal separator (,). bc only knows .. Convert your string containing numeric values by running them through tr , '.' before sending them to bc.
Or, as suggested by tripleee, set the C locale explicitly at the top of the script:
export LC_ALL=C
For more complex locale operations, you may need library support:
https://github.com/leagris/lcnumconv.sh