Triple nested loop python (While loop insde of for loop inside of while loop)

[Isaac Won]

try to make my triple nested loop working. My code would be:
c = 4    
y1 = []    
m1 = []    
std1 = []    
while c <24:    
        c = c + 1    
        a = []    
        f.seek(0,0)    
        for columns in ( raw.strip().split() for raw in f ):    
                a.append(columns[c])    
                x = np.array(a, float)    
        not_nan = np.logical_not(np.isnan(x))    
        indices = np.arange(len(x))    
        interp = interp1d(indices[not_nan], x[not_nan], kind = 'nearest')    
        p = interp(indices)

        N = len(p)    
        dt = 900.0 #Time step (seconds)    
        fs = 1./dt #Sampling frequency    
        KA,PSD = oned_Fourierspectrum(p,dt) # Call Song's 1D FS function    
        time_axis = np.linspace(0.0,N,num = N,endpoint = False)*15/(60*24)     
        plot_freq = 24*3600.*KA #Convert to cycles per day     
        plot_period = 1.0/plot_freq # convert to days/cycle    
        fpsd = plot_freq*PSD    
        d = -1     
        while d <335:     
                d = d + 1     
                y = fpsd[d]     
                y1 = y1 + [y]       
               m = np.mean(y1)
        m1 = m1 + [m]
print m1
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My purpose is make a list of [mean(fpsd[0]), mean(fpsd[1]), mean(fpsd[2]).. mean(fpsd[335])]. Each y1 would be the list of fpsd[d].

I check it is working pretty well before second while loop and I can get individual mean of fpsd[d]. However, with second whole loop, it produces definitely wrong numbers. Would you help me this problem?