Using awk to replace and add text - awk

Question

I have the following .txt file:
##fileformat=VCFv4.0
##FILTER=<ID=PASS,Description="All filters passed">
##Tassel=<ID=GenotypeTable,Version=5,Description="Reference allele is not known. The major allele was used as reference allele">
##FORMAT=<ID=GT,Number=1,Type=String,Description="Genotype">
##FORMAT=<ID=AD,Number=.,Type=Integer,Description="Allelic depths for the reference and alternate alleles in the order listed">
##FORMAT=<ID=DP,Number=1,Type=Integer,Description="Read Depth (only filtered reads used for calling)">
##FORMAT=<ID=GQ,Number=1,Type=Float,Description="Genotype Quality">
##FORMAT=<ID=PL,Number=G,Type=Float,Description="Normalized, Phred-scaled likelihoods for AA,AB,BB genotypes where A=ref and B=alt; not applicable if site is not biallelic">
##INFO=<ID=NS,Number=1,Type=Integer,Description="Number of Samples With Data">
##INFO=<ID=DP,Number=1,Type=Integer,Description="Total Depth">
##INFO=<ID=AF,Number=.,Type=Float,Description="Allele Frequency">
##bcftools_viewVersion=1.12-57-g0c2765b+htslib-1.12-45-g1830551
##bcftools_viewCommand=view -h 20Perc.SNPs.mergedAll.vcf; Date=Tue Sep 28 09:46:59 2021
I would like to make two edits to this text. First, in the line:
##FORMAT=<ID=PL,Number=.,Type=Float,Description="Normalized, Phred-scaled likelihoods for AA,AB,BB genotypes where A=ref and B=alt; not applicable if site is not biallelic">
I would like to replace "Number=." with "Number=G"
And immediately after the after the line:
##INFO=<ID=AF,Number=.,Type=Float,Description="Allele Frequency">
I would like to add a new line of text (& and line break):
##INFO=<ID=QualityScore,Number=.,Type=Float,Description="Quality score">
I was wondering if this could be done with one or two awk commands.
Thanks for any suggestions!

Answer 1

My solution is similar to #Daweo. Consider this script, replace.awk:
/^##FORMAT/ { sub(/Number=\./, "Number=G") }
/##INFO=<ID=AF,Number=.,Type=Float,Description="Allele Frequency">/ {
print
print "##INFO=<ID=QualityScore,Number=.,Type=Float,Description=\"Quality score\">"
next
}
1
Run it:
awk -f replace.awk file.txt
Notes
The first line is easy to understand. It is a straight replace
The next group of lines deals with your second requirements. First, the print statement prints out the current line
The next print statement prints out your data
The next command skips to the next line
Finally, the pattern 1 tells awk to print every lines

Answer 2

I would GNU AWK following way, let file.txt content be
##fileformat=VCFv4.0
##FILTER=<ID=PASS,Description="All filters passed">
##Tassel=<ID=GenotypeTable,Version=5,Description="Reference allele is not known. The major allele was used as reference allele">
##FORMAT=<ID=GT,Number=1,Type=String,Description="Genotype">
##FORMAT=<ID=AD,Number=.,Type=Integer,Description="Allelic depths for the reference and alternate alleles in the order listed">
##FORMAT=<ID=DP,Number=1,Type=Integer,Description="Read Depth (only filtered reads used for calling)">
##FORMAT=<ID=GQ,Number=1,Type=Float,Description="Genotype Quality">
##FORMAT=<ID=PL,Number=G,Type=Float,Description="Normalized, Phred-scaled likelihoods for AA,AB,BB genotypes where A=ref and B=alt; not applicable if site is not biallelic">
##INFO=<ID=NS,Number=1,Type=Integer,Description="Number of Samples With Data">
##INFO=<ID=DP,Number=1,Type=Integer,Description="Total Depth">
##INFO=<ID=AF,Number=.,Type=Float,Description="Allele Frequency">
##bcftools_viewVersion=1.12-57-g0c2765b+htslib-1.12-45-g1830551
##bcftools_viewCommand=view -h 20Perc.SNPs.mergedAll.vcf; Date=Tue Sep 28 09:46:59 2021
then
awk '/##FORMAT=<ID=PL/{gsub("Number=\\.","Number=G")}/##INFO=<ID=AF/{print;print "##INFO=<ID=QualityScore,Number=.,Type=Float,Description=\x22Quality score\x22>";next}{print}' file.txt
output
##fileformat=VCFv4.0
##FILTER=<ID=PASS,Description="All filters passed">
##Tassel=<ID=GenotypeTable,Version=5,Description="Reference allele is not known. The major allele was used as reference allele">
##FORMAT=<ID=GT,Number=1,Type=String,Description="Genotype">
##FORMAT=<ID=AD,Number=.,Type=Integer,Description="Allelic depths for the reference and alternate alleles in the order listed">
##FORMAT=<ID=DP,Number=1,Type=Integer,Description="Read Depth (only filtered reads used for calling)">
##FORMAT=<ID=GQ,Number=1,Type=Float,Description="Genotype Quality">
##FORMAT=<ID=PL,Number=G,Type=Float,Description="Normalized, Phred-scaled likelihoods for AA,AB,BB genotypes where A=ref and B=alt; not applicable if site is not biallelic">
##INFO=<ID=NS,Number=1,Type=Integer,Description="Number of Samples With Data">
##INFO=<ID=DP,Number=1,Type=Integer,Description="Total Depth">
##INFO=<ID=AF,Number=.,Type=Float,Description="Allele Frequency">
##INFO=<ID=QualityScore,Number=.,Type=Float,Description="Quality score">
##bcftools_viewVersion=1.12-57-g0c2765b+htslib-1.12-45-g1830551
##bcftools_viewCommand=view -h 20Perc.SNPs.mergedAll.vcf; Date=Tue Sep 28 09:46:59 2021
Explanation: If current line contains ##FORMAT=<ID=PL change Number=\\. to Number=G (note \ are required to get literal . rather than . meaning any character). If current line contains ##INFO=<ID=AF print it and then print ##INFO=<ID=QualityScore,Number=.,Type=Float,Description=\x22Quality score\x22> (\x22 is hex escape code for ", " could not be used inside " delimited string) and go to next line. Final print-ing is for all lines but those containing ##INFO=<ID=AF as these have own print-ing.
(tested in gawk 4.2.1)