awk, declare array embracing FNR and field, output - arrays

Question

I would like to declare an array of a certain number of lines, that means from line 10 to line 78, as an example. Could be other number, this is just an example.
My sample gives me that range of lines on stdout but sets "1" in between that lines. Can anybody tell me how to get rid of that "1"?
Sample as follows should go to stdout and embraces the named lines.
awk '
myarr["range-one"]=NR~/^2$/ , NR~/^8$/;
{print myarr["range-one"]};' /home/$USER/uplog.txt;
That is giving me this output:
0
12:33:49 up 3:57, 2 users, load average: 0,61, 0,37, 0,22 21.06.2014
1
12:42:02 up 4:06, 2 users, load average: 0,14, 0,18, 0,19 21.06.2014
1
12:42:29 up 4:06, 2 users, load average: 0,09, 0,17, 0,19 21.06.2014
1
12:43:09 up 4:07, 2 users, load average: 0,09, 0,16, 0,19 21.06.2014
1
Second question: how to set in that array one field of FNR or line?
When I do it this way there comes up the field that I wanted
awk ' NR~/^1$/ , NR~/^7$/ {print $3, $11; next} ; ' /home/$USER/uplog.txt;
But I need an array, thats why I'm asking. Any hints? Thanks in advance.

Answer 1

What the example script does
awk '
myarr["range-one"]=NR~/^2$/ , NR~/^8$/;
{print myarr["range-one"]};'
Your script is one of the more convoluted and decidedly less-than-obvious pieces of awk that I've ever seen. Let's take a simple input file:
Line 1
Line 2
Line 3
Line 4
Line 5
Line 6
Line 7
Line 8
Line 9
Line 10
Line 11
Line 12
The output from that is:
0
Line 2
1
Line 3
1
Line 4
1
Line 5
1
Line 6
1
Line 7
1
Line 8
1
0
0
0
0
Dissecting your script, it appears that the first line:
myarr["range-one"]=NR~/^2$/ , NR~/^8$/;
is equivalent to:
myarr["range-one"] = (NR ~ /^#$/, NR ~ /^8$/) { print }
That is, the value assigned to myarr["range-one"] is 1 inside the range of line numbers where NR is equal to 2 and is equal to 8, and 0 outside that range; further, when the value is 1, the line is printed.
The second line:
{print myarr["range-one"]};
print the value in myarr["range-one"] for each line of input. Thus, on the first line, the value 0 is printed. For lines 2 to 8, the line is printed followed by the value 1; for lines after that, the value 0 is printed once more.
What the question asks for
The question is not clear. It appears that lines 10 to 78 should be printed. In awk, there are essentially no variable declarations (we can debate about function parameters, but functions don't seem to figure in this). Therefore, declaring an array is not an option.
awk -v lo=10 -v hi=78 'NR >= lo && NR <= hi { print }'
This would print the lines between line 10 and line 78. It would be feasible to save the values in an array (a in the examples below). Said array could be indexed by NR or with a separate index starting at 0 or 1:
awk -v lo=10 -v hi=78 'NR >= lo && NR <= hi { a[NR] = $0 }' # Indexed by line number
awk -v lo=10 -v hi=78 'NR >= lo && NR <= hi { a[i++] = $0 }' # Indexed from 0
awk -v lo=10 -v hi=78 'NR >= lo && NR <= hi { a[++i] = $0 }' # Indexed from 1
Presumably, you'd also have an END block to do something with the data.
The semicolons in the original are both unnecessary. The blank line is ignored, of course.