"""File:      rand_data.py
   Purpose:   Generate input for the histogram program

   Run:       python rand_data.py

   Input:     
              n:       number of random values
              min_rv:  minimum random value
              max_rv:  maximum random value
              b:       number of bars
              min_v:   min value for smallest subinterval
              max_v:   max value for largest subinterval 
              filename:name of file in which to store output
   Output:    n
              values
              b
              min_v
              max_v
   Note:      The output is formatted so that it can be used as
              input to the histogram program.  
"""
from random import random

#----------------------------------------------------------------------
def gen_vals(vals, n, min_rv, max_rv):
   """Generate n pseudo-random floats between min_rv and max_rv
      Store the floats in vals"""
   for i in range(n):
      x = random()
      y = (max_rv-min_rv)*x + min_rv
      vals.append(y)

#----------------------------------------------------------------------
def print_data(filename, n, vals, b, min_v, max_v):
   """Open filename for writing.  Write remaining values to this file"""
   fout = open(filename, "w")
   fout.write(str(n) + '\n')
   for x in vals:
      fout.write(str(x) + '\n')
   fout.write(str(b) + '\n')
   fout.write(str(min_v) + '\n')
   fout.write(str(max_v) + '\n')
   fout.close

#----------------------------------------------------------------------
# Main program
n = int(raw_input("How many random values?\n   "))
min_rv = float(raw_input("What's the smallest random value?\n   "))
max_rv = float(raw_input("What's the largest random value?\n   "))
vals = []
gen_vals(vals, n, min_rv, max_rv)

b = int(raw_input("How many bars will there be?\n   "))
min_v = float(raw_input("What's the smallest value in the histogram?\n   "))
max_v = float(raw_input("What's the largest value in the histogram?\n   "))

filename = raw_input("What's the name of the output file?\n   ")
print_data(filename, n, vals, b, min_v, max_v)