#+DATE: 2016-08-18
* Programming Languages
-** gnuplog
-
-1. normal
-#+BEGIN_SRC gnuplot :exports code :file ./temp/sin.png
- reset
- plot sin(x)/x
-#+END_SRC
-
-#+RESULTS:
-[[file:./temp/sin.png]]
-
-2. plot with data file
-#+BEGIN_SRC
-
-#+END_SRC
-
-
-* Perl One Line Command
+** Perl
+*** One line command
+**** perl help
#+BEGIN_SRC sh :exports both :results output replace
perl --help
#+END_SRC
#+end_example
-1. Used as =grep=
+**** Used as =grep=
#+BEGIN_SRC sh
perl -ne 'print if /expression/' xxx.log;
#+END_SRC
+#+BEGIN_SRC perl :results output replace
+ my $tt = "hello";
+ ($tt =~ /h(.*)o/ ) and print $1;
+#+END_SRC
+
+#+RESULTS:
+: ell
+
Or
#+BEGIN_SRC sh
perl -wnl -e '/keyword/ and print;' xxx.log
#+END_SRC
-
-2. Used as =awk=
+**** Used as =awk=
#+BEGIN_SRC sh
perl -ne 'print "$1\n" if /aaa=(\d+)\s.*/' xxx.log;
#+END_SRC
-3.
-#+BEGIN_SRC sh
- perl -pe 'some code' < input.txt > output.txt
+#+BEGIN_SRC fundamental :tangle ./temp/aa.txt
+ aa: 1
+ bb: 2
+ cc: 3
+ dd: 4
+#+END_SRC
+
+#+BEGIN_SRC sh :results output replace
+ perl -wnl -e 'print "==$.: $_"' ./temp/aa.txt
+#+END_SRC
+
+#+RESULTS:
+: ==1:
+: ==2: aa: 1
+: ==3: bb: 2
+: ==4: cc: 3
+: ==5: dd: 4
+
+*** Special Variable
+See special variable in perl [[http://perldoc.perl.org/perlvar.html][perlvar]], or =perldoc perlvar=
+- =$.= Current line number
+
+** gnuplog
+
+1. normal
+#+BEGIN_SRC gnuplot :exports code :file ./temp/sin.png
+ reset
+ plot sin(x)/x
#+END_SRC
+#+RESULTS:
+[[file:./temp/sin.png]]
+
+2. plot with data file
+#+BEGIN_SRC fundamental :tangle ./temp/plot.dat
+ # x y
+ 1 11
+ 2 12
+ 3 13
+ 4 14
+ 5 15
+ 6 16
+ 7 17
+ 8 18
+ 9 19
+#+END_SRC
+
+#+BEGIN_SRC gnuplot :file ./temp/ll.png
+ reset
+ set xrange [0:10]
+ set yrange [0:20]
+ plot "./temp/plot.dat" using 1:2 with lines
+#+END_SRC
+
+#+RESULTS:
+[[file:./temp/ll.png]]
+