唯一地删除多个文件中不需要的行。

Question

我需要从多个输出文件中删除不必要的数据，每个文件的一部分如下所示

# BLASTN 2.3.0+
# Query: M03117:99:000000000-ALL7G:1:1101:18697:4431_2:N:0:196
# Database: /home/alex/blast/db/tryps_ITS/tryps_ITS_db
# 0 hits found
# BLASTN 2.3.0+
# Query: M03117:99:000000000-ALL7G:1:1101:26276:5181_1:N:0:196
# Database: /home/alex/blast/db/tryps_ITS/tryps_ITS_db
# Fields: subject title, query acc., subject acc., evalue, q. start, q. end, s. start, s. end
# 1 hits found
FJ712717_(modified) Trypanosoma brucei brucei from mouse 18S ribosomal RNA gene, partial sequence; internal transcribed spacer 1, complete sequence; and 5.8S ribosomal RNA gene, partial sequence  M03117:99:000000000-ALL7G:1:1101:26276:5181_1:N:0:196   FJ712717_(modified) 1.42e-137   1   271 53  323
# BLASTN 2.3.0+
# Query: M03117:99:000000000-ALL7G:1:1101:26276:5181_2:N:0:196
# Database: /home/alex/blast/db/tryps_ITS/tryps_ITS_db
# Fields: subject title, query acc., subject acc., evalue, q. start, q. end, s. start, s. end
# 1 hits found
FJ712717_(modified) Trypanosoma brucei brucei from mouse 18S ribosomal RNA gene, partial sequence; internal transcribed spacer 1, complete sequence; and 5.8S ribosomal RNA gene, partial sequence  M03117:99:000000000-ALL7G:1:1101:26276:5181_2:N:0:196   FJ712717_(modified) 1.06e-87    1   197 436 236
# BLASTN 2.3.0+
# Query: M03117:99:000000000-ALL7G:1:1101:10339:5290_1:N:0:196
# Database: /home/alex/blast/db/tryps_ITS/tryps_ITS_db
# 0 hits found
# BLASTN 2.3.0+
# Query: M03117:99:000000000-ALL7G:1:1101:10339:5290_2:N:0:196
# Database: /home/alex/blast/db/tryps_ITS/tryps_ITS_db
# 0 hits found

前4行表示一个输出结果。

# BLASTN 2.3.0+
# Query: M03117:99:000000000-ALL7G:1:1101:7647:16266_2:N:0:215
# Database: /home/alex/blast/db/tryps_ITS/tryps_ITS_db
# 0 hits found

我需要删除所有0次点击的输出结果，即所有4行(如上所示)。

我注意到，结果是:找到了1次点击，增加了2行。第6行不以"#“符号开头。如何使用

grep -B

命令这么做？我的预期输出是一个只有“找到1次点击”结果的文件。如下所示

# BLASTN 2.3.0+
# Query: M03117:99:000000000-ALL7G:1:1101:26276:5181_1:N:0:196
# Database: /home/alex/blast/db/tryps_ITS/tryps_ITS_db
# Fields: subject title, query acc., subject acc., evalue, q. start, q. end, s. start, s. end
# 1 hits found
FJ712717_(modified) Trypanosoma brucei brucei from mouse 18S ribosomal RNA gene, partial sequence; internal transcribed spacer 1, complete sequence; and 5.8S ribosomal RNA gene, partial sequence  M03117:99:000000000-ALL7G:1:1101:26276:5181_1:N:0:196   FJ712717_(modified) 1.42e-137   1   271 53  323
# BLASTN 2.3.0+
# Query: M03117:99:000000000-ALL7G:1:1101:26276:5181_2:N:0:196
# Database: /home/alex/blast/db/tryps_ITS/tryps_ITS_db
# Fields: subject title, query acc., subject acc., evalue, q. start, q. end, s. start, s. end
# 1 hits found
FJ712717_(modified) Trypanosoma brucei brucei from mouse 18S ribosomal RNA gene, partial sequence; internal transcribed spacer 1, complete sequence; and 5.8S ribosomal RNA gene, partial sequence  M03117:99:000000000-ALL7G:1:1101:26276:5181_2:N:0:196   FJ712717_(modified) 1.06e-87    1   197 436 236
# BLASTN 2.3.0+
# Query: M03117:99:000000000-ALL7G:1:1101:11481:5777_1:N:0:196
# Database: /home/alex/blast/db/tryps_ITS/tryps_ITS_db
# Fields: subject title, query acc., subject acc., evalue, q. start, q. end, s. start, s. end
# 1 hits found
JN673389_(modified) Trypanosoma congolense isolate TS07210 18S ribosomal RNA gene, partial sequence; internal transcribed spacer 1, 5.8S ribosomal RNA gene, and internal transcribed spacer 2, complete sequence; and 28S ribosomal RNA gene, partial sequence M03117:99:000000000-ALL7G:1:1101:11481:5777_1:N:0:196   JN673389_(modified) 2.04e-105   1   231 23  253
# BLASTN 2.3.0+
# Query: M03117:99:000000000-ALL7G:1:1101:11481:5777_2:N:0:196
# Database: /home/alex/blast/db/tryps_ITS/tryps_ITS_db
# Fields: subject title, query acc., subject acc., evalue, q. start, q. end, s. start, s. end
# 1 hits found
TCU22315_(modified) Trypanosoma congolense IL1180 18S, 5.8S, 28S-LS1, srRNA1, complete sequence, and 28S-LS2 ribosomal RNA, partial sequence    M03117:99:000000000-ALL7G:1:1101:11481:5777_2:N:0:196   TCU22315_(modified) 1.40e-75    1   156 1176    1021

Answer 1

您可以使用tac反转文件行，并在匹配模式之前删除3行，包括使用sed包含匹配模式的行，如下所示：

tac filename | sed '/0 hits/I,+3 d' | tac

如果您想就地编辑文件，可以在-i命令中使用sed选项，

tac filename | sed -i '/0 hits/I,+3 d' filename | tac