Emacs/putty code help

Please someone help me with this ruby code on putty/emacs
Thanks

Write a statistical program in Ruby to:

a) Input the name of a data file from the command line arguments.

b) Input floating-point numbers from the data file.

c) Calculate and output the mean. This is the average, or the sum of
the
values divided by the number of values.

d) Calculate and output the median. This is the value such than half
the
values are larger and half are smaller. If you have an even number
of
values use either middle value or the average of the two middle
values.

On Nov 5, 12:12am, Thierry Ntoh yuh [email protected] wrote:

the
Posted viahttp://www.ruby-forum.com/.
I wonder what your teacher will think of this.

ruby -e"a=gets(nil).scan(/[-\d.]+/).map &:to_f;p a.
reduce{|s,x|s+x}/a.size,a.sort[a.size/2]"

On Fri, Nov 5, 2010 at 7:12 AM, Thierry Ntoh yuh [email protected]
wrote:

Please someone help me with this ruby code on putty/emacs
Thanks

Write a statistical program in Ruby to:

a) Input the name of a data file from the command line arguments.

Take a look at ARGV

b) Input floating-point numbers from the data file.

File#readlines and Array#map and String#to_f or Kernel#Float to
transform to floats

c) Calculate and output the mean. This is the average, or the sum of
the
values divided by the number of values.

sum = array.inject {|total,n| total + n} # this gives you the sum of the
values

d) Calculate and output the median. This is the value such than half
the
values are larger and half are smaller. If you have an even number
of
values use either middle value or the average of the two middle
values.

array.sort[array.size / 2] # will sort the array and take the middle
value (or the left side one if even)

Hope this sets you on the right track. Let us know how it goes.

Jesus.