[Quick Hint] Get certain columns from a text file

When printing data to a file, formatting it with some delimiter, is often useful to extract certain columns of it. One way of doing this is opening your favorite spreadsheet software and import the file as csv, copy the columns, and save them on another file.

A quick way of doing this in the terminal is using the "cut" command. If we want to extract columns 3 and 5 of file "myFile", with " " (space) as delimiter and output the result to "myOutputFile", we go:

% cat myFile | cut -d" " -f3,5 > myOutputFile

If you want to extract more columns, just separate them using commas.

That's it!

Source: http://bhoom.wordpress.com/2011/03/02/cut-fixed-width-file-format/

En recuerdo de mi madrina

Su vida se acaba de terminar, la mía va como en la mitad y la de mi hija recién comienza.

Spring break

Se acabó la semana y me voy a Chile por un tiempo. Eso :)

B17 - Liberty Belle

Fuimos con Bernardita al Dekalb-Peachtree Airport y nos encontramos con el Liberty Belle. Nos pudimos subir y todo. No ten'ia c'amara as'i que s'olo logr'e sacar estas fotos lo-fi:

:)

See the full gallery on Posterous

A (just born) cheat sheet

We all love Farkas' Lemma, but we keep forgetting the right version of it that we are needing. Also, we're too lazy to reduce our current system to a version that we do remember.

This is why I've made a modest cheat sheet with a few versions of Farkas' Lemma and a very useful table from Bertsimas' and Tsitsiklis' book for computing dual problems in LP. I know that some may say that you're supposed to know all these by using your intuition... but while we get there, we have the cheat sheet!

Link: A (just born) cheat sheet about Farkas' Lemma and duality.

Eject

Encontré esto al llegar a la oficina hoy...

Eso.

Ouch Report

Bernardita fue rasguñada por un compañero(a) del jardín. Nos dieron un "Ouch Report" al respecto.

La foto parece decir que no lo tomó tan mal :)

Eso.