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Extract date from file name

.everyoneloves__top-leaderboard:empty,.everyoneloves__mid-leaderboard:empty,.everyoneloves__bot-mid-leaderboard:empty{ height:90px;width:728px;box-sizing:border-box;
}

0

I'm trying to extract the date from a filename and storing it to a variable and also needs to change the date format . If I have the name of the file consistent, can I go by position and extract the date?

File Name: GHDC_src_04142019_05_09_32.data.gz

looking the result of that date

04142019 as var=2019-04-14

bash shell

share|improve this question

asked 10 hours ago

Seshi KumarSeshi Kumar

1

New contributor

Seshi Kumar is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.

add a comment | 

0

I'm trying to extract the date from a filename and storing it to a variable and also needs to change the date format . If I have the name of the file consistent, can I go by position and extract the date?

File Name: GHDC_src_04142019_05_09_32.data.gz

looking the result of that date

04142019 as var=2019-04-14

bash shell

share|improve this question

asked 10 hours ago

Seshi KumarSeshi Kumar

1

New contributor

Seshi Kumar is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.

add a comment | 

I'm trying to extract the date from a filename and storing it to a variable and also needs to change the date format . If I have the name of the file consistent, can I go by position and extract the date?

File Name: GHDC_src_04142019_05_09_32.data.gz

looking the result of that date

04142019 as var=2019-04-14

bash shell

share|improve this question

asked 10 hours ago

Seshi KumarSeshi Kumar

1

New contributor

Seshi Kumar is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.

File Name: GHDC_src_04142019_05_09_32.data.gz

04142019 as var=2019-04-14

share|improve this question

asked 10 hours ago

Seshi KumarSeshi Kumar

1

New contributor

Seshi Kumar is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.

share|improve this question

asked 10 hours ago

Seshi KumarSeshi Kumar

1

New contributor

Seshi Kumar is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.

asked 10 hours ago

Seshi KumarSeshi Kumar

1

New contributor

Seshi Kumar is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.

asked 10 hours ago

Seshi KumarSeshi Kumar

1

1 Answer
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1

Since you can "go by position," try:

$ name=GHDC_src_04142019_05_09_32.data.gz

$ echo "${name:13:4}-${name:9:2}-${name:11:2}"

2019-04-14

Or, to save in a variable:

name=GHDC_src_04142019_05_09_32.data.gz

var="${name:13:4}-${name:9:2}-${name:11:2}"

Since this uses pure bash, no subprocess needs to be started and no external command needs to be launched. This makes this approach efficient.

The form ${name:offset:length} is called substring expansion. It selects characters from $name starting at offset and continuing for length. In our case, ${name:13:4} captures the year, ${name:9:2} the month, and ${name:11:2} the day.

share|improve this answer

edited 10 hours ago

answered 10 hours ago

John1024John1024

12.9k43433

add a comment | 

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1

Since you can "go by position," try:

$ name=GHDC_src_04142019_05_09_32.data.gz

$ echo "${name:13:4}-${name:9:2}-${name:11:2}"

2019-04-14

Or, to save in a variable:

name=GHDC_src_04142019_05_09_32.data.gz

var="${name:13:4}-${name:9:2}-${name:11:2}"

Since this uses pure bash, no subprocess needs to be started and no external command needs to be launched. This makes this approach efficient.

The form ${name:offset:length} is called substring expansion. It selects characters from $name starting at offset and continuing for length. In our case, ${name:13:4} captures the year, ${name:9:2} the month, and ${name:11:2} the day.

share|improve this answer

edited 10 hours ago

answered 10 hours ago

John1024John1024

12.9k43433

add a comment | 

1

Since you can "go by position," try:

$ name=GHDC_src_04142019_05_09_32.data.gz

$ echo "${name:13:4}-${name:9:2}-${name:11:2}"

2019-04-14

Or, to save in a variable:

name=GHDC_src_04142019_05_09_32.data.gz

var="${name:13:4}-${name:9:2}-${name:11:2}"

Since this uses pure bash, no subprocess needs to be started and no external command needs to be launched. This makes this approach efficient.

The form ${name:offset:length} is called substring expansion. It selects characters from $name starting at offset and continuing for length. In our case, ${name:13:4} captures the year, ${name:9:2} the month, and ${name:11:2} the day.

share|improve this answer

edited 10 hours ago

answered 10 hours ago

John1024John1024

12.9k43433

add a comment | 

Since you can "go by position," try:

$ name=GHDC_src_04142019_05_09_32.data.gz

$ echo "${name:13:4}-${name:9:2}-${name:11:2}"

2019-04-14

Or, to save in a variable:

name=GHDC_src_04142019_05_09_32.data.gz

var="${name:13:4}-${name:9:2}-${name:11:2}"

Since this uses pure bash, no subprocess needs to be started and no external command needs to be launched. This makes this approach efficient.

The form ${name:offset:length} is called substring expansion. It selects characters from $name starting at offset and continuing for length. In our case, ${name:13:4} captures the year, ${name:9:2} the month, and ${name:11:2} the day.

share|improve this answer

edited 10 hours ago

answered 10 hours ago

John1024John1024

12.9k43433

$ name=GHDC_src_04142019_05_09_32.data.gz

$ echo "${name:13:4}-${name:9:2}-${name:11:2}"

2019-04-14

name=GHDC_src_04142019_05_09_32.data.gz

var="${name:13:4}-${name:9:2}-${name:11:2}"

share|improve this answer

edited 10 hours ago

answered 10 hours ago

John1024John1024

12.9k43433

answered 10 hours ago

John1024John1024

12.9k43433

answered 10 hours ago

John1024John1024

12.9k43433