How to get version number from string in bash-CodePudding

I have a variable having following format
bundle="chn-pro-X.Y-Z.el8.x86_64"

X,Y,Z are numbers having any number of digits
Ex:

1.0-2  # X=1 Y=0 Z=2
12.45-9874 # X=12 Y=45 Z=9874

How can I grab X.Y and store it in another variable?

EDIT:

I wasn't right with my wording, but I want to store X.Y into new variable not individual X & Y's I'm looking to finally have a variable version which has X.Y grabbed from bundle:
version="X.Y"

CodePudding user response：

I would use awk:

bundle="chn-pro-12.45-9874.el8.x86_64"
echo "$bundle" | awk -F "[.-]" '{print $3,$4,$5}'
12 45 9874

Now if you want to assign to x, y, z use read and process substitution:

read -r x y z < <(echo "$bundle" | awk -F "[.-]" '{print $3,$4,$5}')

echo "x=$x, y=$y, z=$z"
x=12, y=45, z=9874

If you just want the value of X.Y as a single value this is still great use for awk:

bundle="chn-pro-12.45-9874.el8.x86_64"
echo "$bundle" | awk -F "[-]" '{print $3}'
12.45

And if you then want to put that into a variable:

x_y=$(echo "$bundle" | awk -F "[-]" '{print $3}')
echo "x_y=$x_y"
x_y=12.45

Or you can use cut in this case to get the third field:

echo "$bundle" | cut -d- -f3
12.45

CodePudding user response：

Like that:

$ bundle="chn-pro-1.0-2.el8.x86_64"
$ X="$(echo "$bundle" | cut -d . -f1 | cut -d- -f3)"
$ Y="$(echo "$bundle" | cut -d . -f2 | cut -d- -f1)"
$ Z="$(echo "$bundle" | cut -d . -f2 | cut -d- -f2)"
$ echo "$X"
1
$ echo "$Y"
0
$ echo "$Z"
2

You can merge X and Y into a single variable:

$ XY="$X.$Y"
$ echo $XY
1.0

CodePudding user response：

Use regex to separate numbers:

numbers=$(echo $bundle | grep -Eo '([0-9] \.[0-9] \-[0-9] )' | sed 's/\./\t/g;s/\-/\t/g')

Then assign them to variables with using awk or tr or cut, whatever you want:

X=$(echo $numbers| awk '{print $1}')
Y=$(echo $numbers| awk '{print $2}')
Z=$(echo $numbers| awk '{print $3}')

EDIT

For storing x.y into single version variable you can simply ignore pervios commands:

version=$(echo $bundle | grep -Eo '([0-9] \.[0-9] \-[0-9] )' | grep -Eo '([0-9] \.[0-9] )')

CodePudding user response：

Given this input:

$ bundle="chn-pro-12.45-9874.el8.x86_64"

using GNU or BSD sed for -E:

$ foo=$(echo "$bundle" | sed -E 's/.*-([0-9] \.[0-9] )-[0-9].*/\1/')
$ echo "$foo"
12.45

or with any sed:

$ foo=$(echo "$bundle" | sed 's/.*-\([0-9][0-9]*\.[0-9][0-9]*\)-[0-9].*/\1/')
$ echo "$foo"
12.45

CodePudding user response：

Assumptions:

the input string will always contain (at least) 3 hyphens
the desired version string will always reside between the 2nd and 3rd hyphens of the input string
we need to maintain the input string (ie, don't clobber/overwrite the variable containing the input string)

We can eliminate the subprocess calls (necessary for echo/sed/grep/awk/sed) by using some parameter expansions:

$ bundle="chn-pro-X.Y-Z.el8.x86_64"

$ temp="${bundle#*-}"                   # strip off 1st hyphen delimited string
$ echo "${temp}"
pro-X.Y-Z.el8.x86_64

$ temp="${temp#*-}"                     # strip off 2nd hyphen delimited string
$ echo "${temp}"
X.Y-Z.el8.x86_64

$ version="${temp%%-*}"                 # save 3rd hyphen delimited string (aka our version)
$ echo "${version}"
X.Y

NOTE: We can eliminate the temp variable by replacing all occurrences of temp with version with the understanding version does not contain what we want until after the 3rd parameter expansion has occurred, eg:

$ bundle="chn-pro-X.Y-Z.el8.x86_64"
$ version="${bundle#*-}"
$ version="${version#*-}"
$ version="${version%%-*}"
$ echo "${version}"
X.Y