Script for pulling data out of a txt file

schapman43 · 08-03-2010, 09:00 AM

I would like to write a script that pulls the last line of data out of a txt file and then saves it to another txt file. The txt file that I am looking at resides here.
http://www.swpc.noaa.gov/ftpdir/list...ulder_iono.txt

I know I can grab that file using wget. I've done a little scripting but nothing major. Can someone push me in the right direction?

Thanks,

anon237 · 08-03-2010, 09:08 AM

Hi,

This will grep the last line of the mentioned file and saves it in foo.txt:

wget -qO - http://www.swpc.noaa.gov/ftpdir/list...ulder_iono.txt | tail -1 > foo.txt

Hope this helps.

lartman · 08-03-2010, 09:21 AM

tail -n 1 > somewhere

schapman43 · 08-03-2010, 11:30 AM

Quote:

Originally Posted by druuna

Hi,

This will grep the last line of the mentioned file and saves it in foo.txt:

wget -qO - http://www.swpc.noaa.gov/ftpdir/list...ulder_iono.txt | tail -1 > foo.txt

Hope this helps.

foo'king awesome! Thank you guys!

anon237 · 08-03-2010, 11:30 AM

You're welcome

schapman43 · 08-03-2010, 11:36 AM

Is there a way to grab a specific line number? Say if I also wanted to grab the following out of the text.
# YR MO DA HHMM foF2 hmF2 MUF(D) D h'F yF2 fMUF h' fxI foF1 foE hmE foEs fbEs ITEC

anon237 · 08-03-2010, 11:39 AM

Hi,

It is probably not clear to me what is is you want.

You want something like this as output ("header" and the last line)?:
# YR MO DA HHMM foF2 hmF2 MUF(D) D h'F yF2 fMUF h' fxI foF1 foE hmE foEs fbEs ITEC
2010 08 03 1600 5.7 305 3.24 3000 305 86 5.3 325 6.4 4.6 3.2 105 3.7 -1.0 10.0

If that is the case:
wget -qO - http://www.swpc.noaa.gov/ftpdir/list...ulder_iono.txt | sed -ne '/# YR MO DA HHMM/p' -e '$p' > foo.txt

If not please elaborate (with an example?).

schapman43 · 08-03-2010, 01:07 PM

Quote:

Originally Posted by druuna

Hi,

It is probably not clear to me what is is you want.

You want something like this as output ("header" and the last line)?:
# YR MO DA HHMM foF2 hmF2 MUF(D) D h'F yF2 fMUF h' fxI foF1 foE hmE foEs fbEs ITEC
2010 08 03 1600 5.7 305 3.24 3000 305 86 5.3 325 6.4 4.6 3.2 105 3.7 -1.0 10.0

If that is the case:
wget -qO - http://www.swpc.noaa.gov/ftpdir/list...ulder_iono.txt | sed -ne '/# YR MO DA HHMM/p' -e '$p' > foo.txt

If not please elaborate (with an example?).

That is what I was looking for.

I am unable to get it to work though. Foo.txt outputs
2010 08 03 1730 5.7 295 3.12 3000 190 90 4.6 270 6.3 4.6 3.4 100 3.6 -1.0 11.2