How to get gene expression value from Arrayexpress

ArrayExpress has a wonderful R package for data search, download and analysis but it doesn't always work in perfection. Therefore it always good to have have an alternative to download the raw data/CEL and analyze it.
How to download expression data set from NCBI GEO HERE

Prerequisite 


We need following R libraries to run the script
  • ArrayExpress 
  • aff

How to perform parallel BLAST

Cheat Sheet to Install and work with R on Ubuntu