Extract information from a list using Tcl - tcl

Question

I have multiple log files which contain values like this with headers :
I want to make a header file which contains each row from column 1 as individual column headers and min - max from each of the row and present it in column format.
Info in log files:
Trace Header Min Max Mean
aaa 1 6 xx
bbb 2 7 xxx
What I want :
aaa bbb
1-6 2-7
Thanks for help

Answer 1

Try this (the long listing is supposed to be in the data variable, read from a file or whatever):
foreach line [split $data \n] {
if {[scan $line {%s %d %d} header min max] eq 3} {
set result($header) $min-$max
}
}
% parray result
result(aaa) = 1-6
result(bbb) = 2-7
The scan command looks for three fields on each line, one text field and two decimal integer fields. A matching line reports three fields found, empty lines or lines with only text report less. If it finds a match, it is added to the result.
ETA:
To deal with the real-world log file you mentioned in a comment:
foreach line [split $data \n] {
if {[scan $line {%59[ #()-./0-9:=>A-Za-z]%s %d %d} header stuff min max] eq 4} {
set result([string trim $header]) $min-$max
}
}
(Note that duplicate headers are compacted into one in the array.)
If you have whitespace in a field, you can't consume the data with %s. Instead you can find out what kind of data the header might contain by using
% set chars [string map {\n {}} [join [lsort -unique [split $data {}]] {}]]
#()-./0123456789:=>ABCDEFGHILMNOPRSTUVWXY[]abcdefghijklmnopqrstuvwxyz
which is easy to simplify to the field specification
[ #()-./0-9:=>A-Za-z]
If you need to able to match brackets, put them in like this:
[][ #()-./0-9:=>A-Za-z]
To split at lines containing uppercase text and blanks, then only equal-signs and possibly more blanks up to line end,
package require textutil::split
::textutil::splitx $data {(?n)^[[:upper:] ]+=+\s*$}
Documentation:
eq (operator),
foreach,
if,
join,
lsort,
package,
parray,
regexp,
Syntax of Tcl regular expressions,
scan,
set,
split,
string,
textutil::split (package)

Answer 2

Code snippet:
set foo {
Info in log files:
Trace Header Min Max Mean
aaa 1 6 xx
bbb 2 7 xxx
}
set pattern {^(.*)\s+(\d+)\s+(\d+)\s+.*$}
set result [regexp -line -inline -all -- $pattern $foo]
array set bar {}
puts "Here's one view..."
foreach {all item min max} $result {
puts "$item $min-$max"
set bar([string trim $item]) $min-$max
}
puts ""
puts "Here's another one..."
puts [join [lsort [array names bar]] "\t"]
foreach item [lsort [array names bar]] {
puts -nonewline "$bar($item)\t"
}
Execution output:
Here's one view...
aaa 1-6
bbb 2-7
Here's another one...
aaa bbb
2-7 1-6