program pt_to_mt
c This program will convert pt specctra in mt-m0 spectra.
c Written be Daniel Cebra 15-Nov-2012
	implicit none
	integer i
	real pt,mt,mtm0,m0,yield,error
	character infile*20,outfile*20

	m0 = 0.93827231
c	m0 = 0.493677
c	m0 = 0.13957

	infile  = "27gev_pim_pt.dat"
	outfile = "27gev_pim_y0.dat"

10	print *," Please input the name of the file to convert"
	read(*,*) infile
	print *," Opening ",infile
	open(4,file=infile,err=10)
20	print *," Please input the name of the file to write"
	read(*,*) outfile
	print *," Opening ",outfile
	open(5,file=outfile,err=20)

	do i = 1,50
	  read(4,*,end=30,err=30)pt,yield,error
	  print 25,pt,yield,error
	  mt = sqrt(m0*m0 + pt*pt)
	  mtm0 = mt - m0
	  print 25,mtm0,yield,error
	  write(5,25)mtm0,yield,error
25	  format(3f12.6)
	end do
30	close(4)
	close(5)

	end