[[snowmass2013:montecarlo| <<back]]


==== How to download the MC samples ====

 

At this moment, you can download the ROOT files from this server. The URL links are provided below. It is recommended to download one-two files and check you code, before downloading the rest.  
You can find the URL location by using the mouse, and clicking on "copy URL link", then you can download one file for testing as:

<code>
wget http://mc.hep.anl.gov/asc/snowmass2013/herwigpp/ttbar650pt/herwigpp_ttbar_pt650_1.root
</code>

On can also download all ROOT files in an automated way.  For example, try this Python script:

<code python download.py>#!/usr/bin/env python
import sys,os,string
__version__ = '1.0'
__author__  = 'Sergei Chekanov  (chekanov@anl.gov)'
if len(sys.argv)<4:
    print "Usage: python download.py nfiles dir name"
    print "Exit.."
    sys.exit()
TOT_FILES=int(sys.argv[1]) # Nr of files to download 
xdir=str(sys.argv[2])
xname=str(sys.argv[3])
print "Nr of files to copy=",TOT_FILES
server="http://mc.hep.anl.gov/asc/snowmass2013/"
print "Copy files from=",server
print xdir+"/"+xname
for i in range(TOT_FILES):
  f=xname+"_"+str(i)+".root"
  cmt="wget --no-check-certificate -N "+server+xdir+"/"+f
  print "Downloading .."+f
  os.system(cmt)
</code>

And run it as:
<code>
python download.py 5 pythia8/ttbar650pt pythia8_ttbar_pt650
</code>

Copy 5 ROOT files to copy from the directory "pythia8/ttbar650pt", all files with the generic  name "pythia8_ttbar_pt650". Change 5 to a larger value
if you need more files.

You can always stop downloading ([Ctrl-C]) and start downloading again from same files. It uses the (‘-N’) option - with this option, for each file it intends to download, wget will check whether a local file of the same name exists. If it does, and the remote file is not newer, Wget will not download it.