title: error FOR3309: undefined label 124
body: <p>I wrote this but when I try to build  *.exe say:</p>
  
  <pre><code>    Compiling Fortran...
  C:\Users\LORD\Desktop\TText1.f90
  C:\Users\LORD\Desktop\TText1.f90(197): error FOR3309: undefined label 124
  Error executing fl32.exe.
  </code></pre>
  
  <p>This is the source code of the project:</p>
  
  <pre><code>      program one
  
  real::x(6),f(6),deltaf1(6),deltaf2(6),deltaf3(6),deltaf4(6),deltaf5(6)
  
  real::gradf1(6),gradf2(6),gradf3(6),gradf4(6),gradf5(6)
  
  real::h,x1,x2,s1,s2,p1,p2,Y1,Y2
  
  real::Z,T,a,b,c,d
  
  open(unit=16,file="E:\N\xi.txt")
  
  open(unit=148,file="E:\N\fi.txt")
  
    gradf1(:)=0.0
    gradf2(:)=0.0
    gradf3(:)=0.0
    gradf4(:)=0.0
    gradf5(:)=0.0
  
    deltaf1(:)=0.0
    deltaf2(:)=0.0
    deltaf3(:)=0.0
    deltaf4(:)=0.0
    deltaf5(:)=0.0
  
  
  do i=0,5
  
  read(16,*)x(i)
  
  read(148,*)f(i)
  
  write(*,12)x(i),f(i)
  
  12 format(2F12.4)
  
  end do
  
  do i=0,4
  
   deltaf1(i)=f(i+1)-f(i)
  
  
   end do
  
    do i=0,3
  
    deltaf2(i)=deltaf1(i+1)-deltaf1(i)
  
      end do
  
      do i=0,2
  
        deltaf3(i)=deltaf2(i+1)-deltaf2(i)
  
  
       end do
  
       do i=0,1
  
          deltaf4(i)=deltaf3(i+1)-deltaf3(i)
  
          write(*,*)deltaf4(i)
  
  
          end do
  
            deltaf5(5)=deltaf4(1)-deltaf4(0)
  
            write(*,*)deltaf5(5)
  
            do i=1,5
  
            gradf1(i)=f(i)-f(i-1)
  
  
            write(*,55)gradf1(i)
  
            55 format(F12.4)
  
              end do
  
      do i=2,5
  
      gradf2(i)=gradf1(i)-gradf1(i-1)
  
      write(*,65)gradf2(i)
  
      65 format(F12.4)
  
      end do
  
      do i=3,5
  
      gradf3(i)=gradf2(i)-gradf2(i-1)
  
      end do
  
  
      do i=4,5
  
      gradf4(i)=gradf3(i)-gradf3(i-1)
  
      write(*,124)gradf4(i)
  
      end do
  
  
      gradf5(5)=gradf4(5)-gradf4(4)
  
      write(*,155)gradf5(5)
  
      155 format(F12.4)
  
  
              h=x(1)-x(0)
  
             x1=0.5
  
            s1=(x1-x(0))/h
  
  
  
  
  
              write(*,33)s1
  
              33 format(F12.4)
  
  !p(x)=fi(0)+s*deltafi1(0)+(1/2)*s*(s-1)*deltafi2(0)+(1/6)*s*(s-1)*(s-2)*deltafi3(0)+(1/24)*s*(s-1)*(s-2)*(s-3)*deltafi4(0)+(1/120)*s*(s-1)*(s-2)*(s-3)*(s-4)*deltafi5(0)   
  
  p1=f(0)+s1*deltaf1(0)+(1/2)*s1*(s1-1)*deltaf2(0)+(1/6)*s1*(s1-1)*(s1-2)*deltaf3(0)+(1/24)*s1*(s1-1)*(s1-2)*(s1-3)*deltaf4(0)+(1/120)*s1*(s1-1)*(s1-2)*(s1-3)*(s1-4)*deltaf5(0)
  
  
      write(*,*)" vaghti x1=0.5 chand jomleie pishro barabar ast ba=",p1
  
      x2=0.45
  
      s2=(x2-x(0))/h
  
      p2=f(0)+s2*deltaf1(0)+(1/2)*s2*(s2-1)*deltaf2(0)+(1/6)*s2*(s2-1)*(s2-2)*deltaf3(0)+(1/24)*s2*(s2-1)*(s2-2)*(s2-3)*deltaf4(0)+(1/120)*s2*(s2-1)*(s2-2)*(s2-3)*(s2-4)*deltaf5(0)
  
  write(*,*)"vaghti x2=0.45 chand jomleie pishro barabar ast ba=",p2
  
      !Y(x)=fi(5)+s*gradfi1(5)+(1/2)*s*(s+1)*gradfi2(5)+(1/6)*s*(s+1)*(s+2)*gradfi3(5)+(1/24)*s*(s+1)*(s+2)*(s+3)*gradfi4(5)+(1/120)*s*(s+1)*(s+2)*(s+3)*(s+4)*gradfi5(5)
  
  
  
      Y1=f(5)+s1*gradf1(5)+(1/2)*s1*(s1+1)*gradf2(5)+(1/6)*s1*(s1+1)*(s1+2)*gradf3(5)+(1/24)*s1*(s1+1)*(s1+2)*(s1+3)*gradf4(5)+(1/120)*s1*(s1+1)*(s1+2)*(s1+3)*(s1+4)*gradf5(5)
  
      write(*,*)"vaghti x1=0.5 chand jomleie pishro barabar ast ba=",Y1
  
      Y2=f(5)+s2*gradf1(5)+(1/2)*s2*(s2+1)*gradf2(5)+(1/6)*s2*(s2+1)*(s2+2)*gradf3(5)+(1/24)*s2*(s2+1)*(s2+2)*(s2+3)*gradf4(5)+(1/120)*s2*(s2+1)*(s2+2)*(s2+3)*(s2+4)*gradf5(5)
  
       write(*,*)"vaghti x2=0.45 chand jomleie pasro barabar ast ba=",Y2
  
       T=abs(p1-Y1)
  
      Z=abs(p2-Y2)
  
      write(*,*)"tafazole chand jomleie pishro va pasro baraye x1=0.5 barabar ast ba=",T
  
      write(*,*)"tafazole chand jomleie pishro va pasro baraye x2=0.45 barabar ast ba=",Z
  
      ! tabe W ra be in shekl benvis=exp(2*x)
  
      !W=exp(2*x)
  
      W1=exp(2*x1)
  
      W2=exp(2*x2)
  
  
      a=abs(p1-W1)
  
      b=abs(p2-W2)
  
      c=abs(Y1-W1)
  
      d=abs(Y2-W2)
  
  
      write(*,*)"tafazole chand jomleie pishro va tabe W mord nazar dr noghte x1=0.5 mishavad=",a
  
  
      write(*,*)"tafazole chand jomleie pishro va tabe W mord nazar dr noghte x2=0.45 mishavad=",b
  
  
      write(*,*)"tafazole chand jomleie pasro va tabe W mord nazar dr  noghte x1=0.5 mishavad=",c
  
  
      write(*,*)"tafazole chand jomleie pasro va tabe W mord nazar dr noghte x2=0.45 mishavad=",d
  
   stop
  end program one
  </code></pre>