{"id":1592,"date":"2014-11-14T15:18:46","date_gmt":"2014-11-14T15:18:46","guid":{"rendered":"http:\/\/ixyzero.com\/blog\/?p=1592"},"modified":"2014-11-14T15:18:46","modified_gmt":"2014-11-14T15:18:46","slug":"awk%e5%ad%a6%e4%b9%a0_4","status":"publish","type":"post","link":"https:\/\/ixyzero.com\/blog\/archives\/1592.html","title":{"rendered":"AWK\u5b66\u4e60_4"},"content":{"rendered":"
\u5982\u4f55\u7528awk\u5b9e\u73b0\u6253\u5370\u6307\u5b9a\u5217\u7684\u529f\u80fd\uff1f<\/h6>\n

Print all but the first three columns
\nToo cumbersome:<\/p>\n

awk '{print \" \"$4\" \"$5\" \"$6\" \"$7\" \"$8\" \"$9\" \"$10\" \"$11\" \"$12\" \"$13}' things<\/pre>\n
\n
A solution that does not add extra leading or trailing whitespace:<\/p>\n
awk '{for(i=4;i<NF;i++)printf \"%s\",$i OFS; if (NF) printf \"%s\",$NF; printf ORS}'<\/pre>\n
Demo:<\/p>\n
$ echo '1 2 3 4 5 6 7' |\n  awk '{for(i=4;i<NF;i++) printf\"%s\",$i OFS;if(NF)printf\"%s\",$NF;printf ORS}' |\n  tr ' ' '-'\n4-5-6-7<\/pre>\n
Another approach using the ternary operator is Sudo_O’s solution:<\/p>\n
$ echo '1 2 3 4 5 6 7' |\n  awk '{for(i=4;i<=NF;i++)printf \"%s\",$i (i==NF?ORS:OFS)}' | tr ' ' '-'\n4-5-6-7<\/pre>\n
And EdMorton gives a solution that preserves the original whitespace between fields:<\/p>\n
$ echo '1 2 3 4 5 6 7' |\n  awk '{sub(\/([^ ]+ +){3}\/,\"\")}1' | tr ' ' '-'\n4---5----6-7<\/pre>\n
The solution given by larsr in the comments is almost correct:<\/p>\n
$ echo '1 2 3 4 5 6 7' |\n  awk '{for (i=3;i<=NF;i++) $(i-2)=$i; NF=NF-2; print $0}' | tr ' ' '-'\n3-4-5-6-7<\/pre>\n
This is the fixed and parametrized version of larsr solution:<\/p>\n
$ echo '1 2 3 4 5 6 7' |\n  awk '{for(i=n;i<=NF;i++)$(i-(n-1))=$i;NF=NF-(n-1);print $0}' n=4 | tr ' ' '-'\n4-5-6-7<\/pre>\n
All other answers are nice but add extra spaces:<\/p>\n
Example of answer adding extra leading spaces:<\/p>\n
$ echo '1 2 3 4 5 6 7' | awk '{$1=$2=$3=\"\"}1' | tr ' ' '-'\n---4-5-6-7<\/pre>\n
Example of answer adding extra trailing space<\/p>\n
$ echo '1 2 3 4 5 6 7' |\n  awk '{for(i=4;i<=13;i++)printf \"%s \",$i;printf \"n\"}' file | tr ' ' '-'\n4-5-6-7-<\/pre>\n
====<\/p>\n
$ awk '{for(i=1;i<4;i++) $i=\"\";print}' file<\/pre>\n
use cut<\/p>\n
$ cut -f4-13 file<\/pre>\n
or if you insist on awk and $13 is the last field<\/p>\n
$ awk '{$1=$2=$3=\"\";print}' file<\/pre>\n
else<\/p>\n
$ awk '{for(i=4;i<=13;i++)printf \"%s \",$i;printf \"n\"}' file<\/pre>\n
====
\nThe correct way to do this is with an RE interval because it lets you simply state how many fields to skip, and retains inter-field spacing for the remaining fields.<\/p>\n
e.g. to skip the first 3 fields without affecting spacing between remaining fields given the format of input we seem to be discussing in this question is simply:<\/p>\n
$ echo '1 2 3 4 5 6' | awk '{sub(\/([^ ]+ +){3}\/,\"\")}1'\n4 5 6<\/pre>\n
If you want to accommodate leading spaces and non-blank spaces, but again with the default FS, then it’s:<\/p>\n
$ echo ' 1 2 3 4 5 6' | awk '{sub(\/[[:space:]]*([^[:space:]]+[[:space:]]+){3}\/,\"\")}1'\n4 5 6<\/pre>\n
If you have an FS that’s an RE you can’t negate in a character set, you can convert it to a single char first (RS is ideal if it’s a single char since an RS CANNOT appear within a field, otherwise consider SUBSEP), then apply the RE interval subsitution, then convert to the OFS. e.g. if chains of “.”s separated the fields:<\/p>\n
$ echo '1...2.3.4...5....6' | awk -F'[.]+' '{gsub(FS,RS);sub(\"([^\"RS\"]+[\"RS\"]+){3}\",\"\");gsub(RS,OFS)}1'\n4 5 6<\/pre>\n
Obviously if OFS is a single char AND it can’t appear in the input fields you can reduce that to:<\/p>\n
$ echo '1...2.3.4...5....6' | awk -F'[.]+' '{gsub(FS,OFS); sub(\"([^\"OFS\"]+[\"OFS\"]+){3}\",\"\")}1'\n4 5 6<\/pre>\n
Then you have the same issue as with all the loop-based solutions that reassign the fields – the FSs are converted to OFSs. If that’s an issue, you need to look into GNU awks’ patsplit() function.<\/p>\n
====
\nPretty much all the answers currently add either leading spaces, trailing spaces or some other separator issue. To select from the fourth field where the separator is whitespace and the output separator is a single space using awk would be:<\/p>\n
$ awk '{for(i=4;i<=NF;i++)printf \"%s\",$i (i==NF?ORS:OFS)}' file<\/pre>\n
To parametrize the starting field you could do:<\/p>\n
$ awk '{for(i=n;i<=NF;i++)printf \"%s\",$i (i==NF?ORS:OFS)}' n=4 file<\/pre>\n
And also the ending field:<\/p>\n
$ awk '{for(i=n;i<=m=(m>NF?NF:m);i++)printf \"%s\",$i (i==m?ORS:OFS)}' n=4 m=10 file<\/pre>\n
\u5b9e\u9645\u6d4b\u8bd5\u6548\u679c\uff1a<\/h6>\n
# echo '1 2 3 4 5 6 7'\n1 2 3 4 5 6 7\n# echo '1 2 3 4 5 6 7' | awk '{for(i=1;i<4;i++) $i=\"\";print}'\n4 5 6 7\n# echo '1 2 3 4 5 6 7' | awk '{$1=$2=$3=\"\";print}'\n4 5 6 7\n#\n# echo '1 2 3 4 5 6 7' | awk '{for(i=4;i<NF;i++)printf \"%s\",$i OFS; if (NF) printf \"%s\",$NF; printf ORS}'\n4 5 6 7\n#\n# echo '1 2 3 4 5 6 7' | awk '{sub(\/([^ ]+ +){3}\/,\"\")}1'\n4 5 6 7\n#\n# echo '1 2 3 4 5 6 7' | awk '{ for (i=3; i<=NF; i++) print $i }'\n3\n4\n5\n6\n7\n# echo '1 2 3 4 5 6 7' | awk '{$1=$2=$3=\"\"}sub(\"^\"FS\"*\",\"\")'\n4 5 6 7<\/pre>\n
\u53c2\u8003\u94fe\u63a5\uff1a<\/h6>\n
Print all but the first three columns<\/a><\/p>\n
==<\/p>\n
\u5982\u4f55\u5220\u9664\u8f93\u51fa\u4e2d\u7684\u524d\/\u540e\u5bfc\u7a7a\u683c\uff08\u7c7b\u4f3c\u4e8etrim\u7684\u4f5c\u7528\uff09\uff1f<\/h6>\n