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-====== Find Longest Line in a File ======
-<code bash>
-awk ' { if ( length > x ) { x = length } }END{ print x }' file.txt
-</code>
-====== Perform Floating Point Calculations ======
-''awk'' can be used for complex calculations, for example:
-<code bash>
-awk 'BEGIN {printf "%.3f\n", sin(30 * atan2(0, -1)/180)}'
-</code>
-will calculate $\sin(30^\circ)=sin(30rad * \frac{\pi}{180})$ and return:
-<code>
-.500
-</code>
-Since ''awk'' does not have a constant for $\pi$, we use ''atan2(0, -1)'' instead.
-====== Delimiter-Style ======
-Suppose you have a file ''input'' containing data separated by delimiters such as:
-<code>
-variable = value
-</code>
-or:
-<code>
-variable = value
-</code>
-The following command can be used to obtain ''value'':
-<code bash>
-awk -F"[ \t]*[=][ \t]*" '{ print $2 }' input
-</code>
-====== Remove Duplicate Entries in File Without Sorting ======
-To remove all duplicates from ''file.txt'' without sorting, issue:
-<code bash>
-awk '!x[$0]++' file.txt
-</code>
-====== Merge Lines by Two in File ======
-Given a file with the contents:
-<code>
-Q: What is this?
-A: This is a FAQ!
-</code>
-and you would like to achieve:
-<code>
-Q: What is this? A: This is a FAQ!
-</code>
-then the following ''awk'' one liner:
-<code bash>
-awk 'NR%2{printf "%s ",$0;next;}1' yourFile
-</code>
-will merge all the lines in a file by two.