Strings and floats in a bash script.

[alb22]

Hi,

there's some thing I just can't get going. After googling a while I didn't find any real clue, so hopefully some of you guys have some hint about this:

There a re two files: ONE.TXT and TWO.TXT which contain floats - one for each line. To read the files into an array, I do this:

DATA1=$(grep '' ONE.TXT)
DATA2=$(grep '' TWO.TXT)

Anything I do with these arrays works pretty fine. Until I try to compare the elements of each one, i.e. compare the first element of DATA1 with the first one of DATA2 a.s.o.
Code looks like this:

n=0
for VAL1 in $DATA1; do
let n=$n+1
m=0
for VAL2 in $DATA2; do
let m=$m+1
if [ $m -eq $n ]; then
#----------------------------
if [ VAL1 -ge VAL2 ]; then
....
fi
#----------------------------
fi
done
done

So.. I tried to some stuff to convert VAL1 and VAL2 into "integers" first, as the bash wants them, trying stuff like this:

V1=`echo $VAL1/1 | bc -l`
V1=$(expr $VAL1/1)

to do afterwards:

if [ $V1 -ge $V2 ]; then

Nothing worked. To sum up the long speech: How do I convert a string in my $DATA1 into a number?


Regards..

[tpl]

welcome to the forum

bash may not be the best tool. You have two files

one.txt
a1
b1
c1
.
.
.

two.txt
a2
b2
c2
.
.
.

you want to compare a1 with a2--> some action depending?

use the "join" utility to get

one.two.txt
a1 a2
b1 b2
c1 c2
. .
. .
. .

then you can use "awk" to compare the a's, b's
etc:

awk '$1>$2 {print $1}' <one.two.txt

[vsemaska]

If you need to compare two floats, use the bc utility as follows:

GE=`echo "if ($VAL1 >= $VAL2) print 1 else print 0" | bc -l`
if [ $GE = 1 ]; then echo "greater than or equal"; fi

[burschik]

You can also use something slightly more simple, like

echo "1 < 2" | bc

which will return 1 for true and 0 for false.

[alb22]

So.. with your help my problem's solved now. Many thanks guys!