Difference between FFT and DFT spectrum! why ?!

Hi every body, can some one help me to understand the reason of difference between the spectrum of the DFT(raw formulas) and FFT which I have implemented via the following code? I am investigating the harmonics up to 9 KHZ for a signal with 50 hz basic frequency and the differences appear mostly in ranges higher than 6 KHz.

I have run this code on a set of samples with 10004 samples which is attached to this post .(just import the variables to matlab and run the code below )

for DFT I have used the formulas in yhe below link : DFT formula

CODE:

%%reading in the samples 
wave; %%%a 10004 samples signal with basic frequency of 50 Hz which means 10 complete period of the fundametal wave 

%%Normal FFT  
wavefft1 = fft(wave);

L=size(wave,1)-1; % removing the mirror side of spectrum
MagSpec1 = abs(wavefft1(1:1801))/(L/2);   %%removing the mirror side of the spectrum 
                                           % and ranging the domain 

%%DFT implementation 
f = 49.985004498650405;  %%f = 10/(time(10004)-time(1))  we have used 10 because these samples consist of 10 periods of the signal with 50 Hz frequency 
Sampling_Fequency = 50000;

N = size (wave,1)

ll = 0;
for k = 0: f/10:180*f;
    cplx_val =0;
    for x = 1:N
        Teta = ((2*pi*k*x)/Sampling_Fequency);
        cplx_val = cplx_val+(wave(x,1)*complex(cos(Teta),(-1*sin(Teta))));
    end
    ll = ll+1;

      MagSpec2(ll,1) = (floor((abs(cplx_val)/(N/2))*10^6))/10^6; %%removing the mirror side of the spectrum 
                                                                  % and ranging the domain
  end

%%drawing the caomparison plot 

set(0,'DefaultFigureVisible','on');
figure;
x1 = (0:1800)*5;
plot(x1,MagSpec1,'r-');hold on;
plot(x1,MagSpec2,'g-');
legend('FFT Normal','DFT');

[Salaheddin Hosseinzadeh]

Ali you can attach your code and sample image here! It's probably easier for lazy ppl like me.

[Ali]

thanks for your hint. I attached the files.

Answer 1

[Matt J]

    omega=exp(-(2*pi/N)*(0:N-1));
    j=sqrt(-1);

    for k=N:-1:1

     DFT(k) = ( omega.^(j*(k-1)) )*wave(:);

    end

[Ali]

thanks a lot.