Here's a simple solution with an hash of array . There might be a better way, tho ... 
use strict ;
use warnings ; 
my $vec ;
my %rez ; 
my $cpt = 0 ;
my $maxcpt = 0;

foreach my $item  (<DATA>) {

    chomp $item ; 

    next if $item =~ m/^}$/ ;
    
    if ( $item =~ m/^v_(.*) {/ ) {
    
        $vec = $1 ; 
        $maxcpt = $cpt if $cpt > $maxcpt ;
        $cpt = 0 ; 
            
    } else { 
    
        $rez{$vec}[$cpt] = $item  ;
        $cpt ++ ;
        
    }

}


foreach my $cpt (0..$maxcpt) {

    foreach my $vec ( keys %rez ) {
    
        if (defined $rez{$vec}[$cpt]) { 
        
            print $rez{$vec}[$cpt], "\t"

        } else { print "\t" } ; 

    }
    
    print "\n" 

}



__DATA__ 
v_x {
x1
x2
x3
x4
x5
x6
x7
x8
}
v_y {
y1
y2
y3
y4
y5
}
v_z {
z1
z2
z3
z4
z5
z6
}

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In reply to Re: text processing - convert list of vectors to tabular format by secret
in thread text processing - convert list of vectors to tabular format by vnpenguin

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