Shell Programming and Scripting

Dear all,

I'm a new guy in Linux scripting. Basically, I have no idea on how to write a script.

Now, I have a problem in preparing my gaussian inputs.
For example, I have a file like this

File name: input.gjf

Code:

H 1.418400 1.180500 -1.247900
H -1.894500 1.628800 -0.000200
Product
H 1.852200 1.607500 -0.107200
H -1.439600 1.956100 -0.069400

I want get a new modified file, like this
newinput.gjf

Code:

H 1.418400 1.180500 -1.247900
H -1.894500 1.628800 -0.000200

Product

1 5
H 1.852200 1.607500 -0.107200
H -1.439600 1.956100 -0.069400

Simply to say, I want to 1) find the line "Product"; 2) add an blank line before line "Product"; 3) add an blank line and line with content "1 5"after it.
I'm wondering by using "awk" to find the line and print these four new lines(two blank lines and a line with "1 5"). Is that possible?

Thank you in advance!

Please help me~~ Grazie!

Code:

awk '$0 ~ "Product" { $0="\nProduct\n\n1 5" } {print}' t
H 1.418400 1.180500 -1.247900
H -1.894500 1.628800 -0.000200

Product

1 5
H 1.852200 1.607500 -0.107200
H -1.439600 1.956100 -0.069400

t is the input file with the contents you have shown.

Awk syntax:
/^Product/ { print ""
print $0
print ""
print "1 5"
next
}
{ print } # default for other lines

OK, both work! thanks a lot.

Shorter

Code:

awk '/Product/{$0=RS$0RS}1' file

Shorter, but incomplete.

Code:

sed 's/^Product/\n&\n\n1 5/' infile