lehrblogger

Bitly tech talk 4/22/2010

On 4/22 we held a bit.ly tech talk on 'Command Line Fu', where we invited talented hackers to come share their best moves. Please correct my notes and add your fu here!

# @jehiah

# in place file regex replacement
perl -pi -e 's/this/that/g' filename_pattern

# print the last column of a file ($NF stands for 'Number of Fields' or more commonly Last Field).

lehrblogger

function (key, values, rereduce) {
        // value -> [count, min, max, mean]
        var i = 0
          , l = values.length
          , min = values[i][2] // set min to the first max
          , max = 0
          , weighted_sum_of_means = 0
          , count = 0
          , cur_count // just for clarity, feel free to remove later
          , cur_min