I have two numbers:
value1=686
value2=228.35
I am not able to add an integer and a float. Please help me out to get the result.
I am running it in bash.
echo 1 + 3.5 | bc
awk "BEGIN {print 1+3.5; exit}"
python -c "print 1+3.5"
perl -e "print 1+3.5"
Just replace the numbers with your variables, eg: echo $n1 + $n2 | bc
If you have the bc language installed, you can do the following:
#!bin/bash
numone=1.234
numtwo=0.124
total=`echo $numone + $numtwo | bc`
echo $total
If you don't have bc, then you can try with awk. Just in one single line:
echo 1.234 2.345 | awk '{print $1 + $2}'
There are plenty of other options, also. Like python, perl, php....
Bash doesn't have floating-point types, but you can use a calculator such as bc:
a=686
b=228.35
c=`echo $a + $b | bc`
echo "$c"
#!/bin/Bash
echo "Enter the two numbers to be added:"
read n1
read n2
answer=$(($n1+$n2))
echo $answer
Related
I am trying to calculate below formula and store the value to a variable.
The pseudo code should look like:
a=10
b=5
c=$(((($a-$b)/52)) | bc -l)
echo $c
The result is empty. I couldn't figure out the syntax using bc. Please help me use bc instead of awk or other method.
There are two things you need to be aware of. The first is that bc uses standard input for expressions so you would need to actually pipe your expression through it, or use the <<< redirection operator, one of:
c=$(echo "($a - $b) / 52" | bc)
c=$(bc <<< "($a - $b) / 52")
The <<< method is specific to bash and ksh (an possibly others, but I'm not really au fait with them). The other method can be used in most shells.
Secondly, you should be careful when using big numbers for this since bc has the annoying habit of splitting them across lines:
pax$ x=999999999999999999999999999999999999999999999999999999999999999999999
pax$ echo "$x / 7" | bc
14285714285714285714285714285714285714285714285714285714285714285714\
2
In order to avoid this, you need to change the line length:
pax$ echo "$x / 7" | BC_LINE_LENGTH=0 bc
142857142857142857142857142857142857142857142857142857142857142857142
You can use this:
a=10
b=5
c=$(bc -l <<< "($a-$b)/52")
echo "$c"
.09615384615384615384
Or by setting a scale of 3:
c=$(bc -l <<< "scale=3; ($a-$b)/52")
echo "$c"
.096
I have a file with 1800 lines that look like this
600.76
600.66
700.44
566.66
Ect..
I made a bash script to calculate the mean.
Now I first made a variable to count the total column lines like:
Lines="$(awk 'END{print NR}' file.txt)"
Then another variable for the sum of that column like this:
Sum="$(awk '{s+1=$1}END {print s}' file.txt)"
Lastly I'm finding the mean like this:
Echo "scale=2 ; $Sum / $Lines" | bc
With debugging enabled It returns:
+echo 'scale=2 ; 1.72161e+06 / 1800'
(Standard_1): syntax error
I realize now bc doesn't do scientific notation but how do I get around this.
I'm OK with short handing the decimal by restricting it to 2 or 3 places.
Unnecessary to use awk. Simple oneliner can do the job.
echo "scale=2; ("$(paste -sd+ file.txt)")"/$(wc -l <file.txt)|bc
Use bc -l for both summation and final division:
sum=0
count=0
while read number; do
number=$(printf "%f\n" $number) # get rid of scientific notation
sum=$(echo "$sum" '+' "$number" | bc -l)
count=$((count + 1))
done < input
avg=$(echo $sum / $count | bc -l)
echo $avg
Greetings!
I uses bс to make some calculations in my script. For example:
bc
scale=6
1/2
.500000
For further usage in my script I need "0.500000" insted of ".500000".
Could you help me please to configure bc output number format for my case?
In one line:
printf "%0.6f\n" $(bc -q <<< scale=6\;1/2)
Just do all your calculations and output in awk:
float_scale=6
result=$(awk -v scale=$floatscale 'BEGIN { printf "%.*f\n", scale, 1/2 }')
As an alternative, if you'd prefer to use bc and not use AWK alone or with 'bc', Bash's printf supports floating point numbers even though the rest of Bash doesn't.
result=$(echo "scale=$float_scale; $*" | bc -q 2>/dev/null)
result=$(printf '%*.*f' 0 "$float_scale" "$result")
The second line above could instead be:
printf -v $result '%*.*f' 0 "$float_scale" "$result"
Which works kind of like sprintf would and doesn't create a subshell.
Quick and dirty, since scale only applies to the decimal digits and bc does not seem to have a sprintf-like function:
$ bc
scale = 6
result = 1 / 2
if (0 <= result && result < 1) {
print "0"
}
print result;
echo "scale=3;12/7" | bc -q | sed 's/^\\./0./;s/0*$//;s/\\.$//'
I believe here is modified version of the function:
float_scale=6
function float_eval()
{
local stat=0
local result=0.0
if [[ $# -gt 0 ]]; then
result=$(echo "scale=$float_scale; $*" | bc -q | awk '{printf "%f\n", $0}' 2>/dev/null)
stat=$?
if [[ $stat -eq 0 && -z "$result" ]]; then stat=1; fi
fi
echo $result
return $stat
}
Can you put the bc usage into a little better context? What are you using the results of bc for?
Given the following in a file called some_math.bc
scale=6
output=1/2
print output
on the command line I can do the following to add a zero:
$ bc -q some_math.bc | awk '{printf "%08f\n", $0}'
0.500000
If I only needed the output string to have a zero for formatting purposes, I'd use awk.
I'm trying to study for a test and one of the subjects are bash scripts.
I have the following txt file :
123456 100
654321 50
203374111 86
I need to get the averages of the scores (the numbers in the second column).
This is what I have written :
cat $course_name$end | while read line; do
sum=`echo $line | cut -f2 -d" "`
let total+=$sum
done
I have tried with
while read -a line
and then
let sum+=${line[1]}
But I'm still getting the same error mentioned in the header.
I love AWK:
awk -F\* '{sum+=$3} END {print sum/NR}' x.txt
So in x.txt are values are stored. Please note that many answers don't actually compute the average, as they need to divide by the line numbers in the end. Often it will be performed by a wc -l < x.txt but in my solution you will get it almost for free.
cat your_file_name.txt | cut -f2 -d" " | paste -sd+ | bc
This should do the job!
You are very close, this works for me:
while read line; do
sum=$(echo $line | cut -f2 -d" ")
echo "sum is $sum"
let total+=$sum
echo "total is $total"
done < file
echo "total is $total"
As you can see, there is no need to use cat $course_name$end, it is enough to do
while read line
do
done < file
Also, it is more recommendable to use
sum=$(echo $line | cut -f2 -d" ")
rather than
sum=`echo $line | cut -f2 -d" "`
Or even
sum=$(cut -f2 -d" " <<< "$line")
There's no need to use cat as well as read; you can redirect the contents of the file into the loop. You also don't need to use let for arithmetic.
sum = 0
count = 0
while read id score; do
(( sum += score )) && (( ++count ))
done < "$course_name$end"
echo $(( sum / count ))
This will give you an integer result, as bash doesn't do floating point arithmetic. To get a floating point result, you could use bc:
bc <<< "scale=2;$a/$b"
This will give you a result correct to 2 decimal places.
Greetings!
I uses bс to make some calculations in my script. For example:
bc
scale=6
1/2
.500000
For further usage in my script I need "0.500000" insted of ".500000".
Could you help me please to configure bc output number format for my case?
In one line:
printf "%0.6f\n" $(bc -q <<< scale=6\;1/2)
Just do all your calculations and output in awk:
float_scale=6
result=$(awk -v scale=$floatscale 'BEGIN { printf "%.*f\n", scale, 1/2 }')
As an alternative, if you'd prefer to use bc and not use AWK alone or with 'bc', Bash's printf supports floating point numbers even though the rest of Bash doesn't.
result=$(echo "scale=$float_scale; $*" | bc -q 2>/dev/null)
result=$(printf '%*.*f' 0 "$float_scale" "$result")
The second line above could instead be:
printf -v $result '%*.*f' 0 "$float_scale" "$result"
Which works kind of like sprintf would and doesn't create a subshell.
Quick and dirty, since scale only applies to the decimal digits and bc does not seem to have a sprintf-like function:
$ bc
scale = 6
result = 1 / 2
if (0 <= result && result < 1) {
print "0"
}
print result;
echo "scale=3;12/7" | bc -q | sed 's/^\\./0./;s/0*$//;s/\\.$//'
I believe here is modified version of the function:
float_scale=6
function float_eval()
{
local stat=0
local result=0.0
if [[ $# -gt 0 ]]; then
result=$(echo "scale=$float_scale; $*" | bc -q | awk '{printf "%f\n", $0}' 2>/dev/null)
stat=$?
if [[ $stat -eq 0 && -z "$result" ]]; then stat=1; fi
fi
echo $result
return $stat
}
Can you put the bc usage into a little better context? What are you using the results of bc for?
Given the following in a file called some_math.bc
scale=6
output=1/2
print output
on the command line I can do the following to add a zero:
$ bc -q some_math.bc | awk '{printf "%08f\n", $0}'
0.500000
If I only needed the output string to have a zero for formatting purposes, I'd use awk.