Re: problem using nested parallel

[Hans Schou]

On Sun, 1 May 2011, Ole Tange wrote:

> parallel -k echo {1}/output/{2} :::: filename <(seq 19 22)

That would only output one line from 'filename' and first number from 
seq. I think he want to run 19 20 21 and 22 with each line from 
filename.

Example
  echo a > filename
  echo b >> filename
  for v1 in $(cat filename); do
    for v2 in $(seq 19 22); do
       echo $v1 $v2
    done
  done
Output:
a 19
a 20
a 21
a 22
b 19
b 20
b 21
b 22

An example which could go with the man page could be:

Find all image files and create two thumb nails images of each.

I don't know who to write it one one line so here is 2 lines which 
does it:

find . -name '*.JPG' | parallel echo convert {} -geometry 150 {.}_150.JPG

find . -name '*.JPG' | parallel echo convert {} -geometry 400 {.}_400.JPG

(which would make thumb nails of the thumb nails)

/hans
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