In [19]: 
import scipy.signal

def plotspec(x, Ts):
    fig = figure()
    ax1 = fig.add_subplot(211)
    ax1.plot(x)
    
    q = fft.fft(x)
    ax2 = fig.add_subplot(212)
    ax2.plot(fft.fftfreq(len(x), Ts), abs(q))
In [2]: 
f = 20
Ts = 1/100.0
time=20

t = linspace(Ts, time, time/Ts)
w=sin(2*pi*f*t)
over=100.0
intfac=1.0
tnow = linspace(10.0/Ts, 10.5/Ts, 0.5/(Ts/intfac)).astype(int)



wsmooth = zeros(len(tnow))
for j in range(len(tnow)):
    i = tnow[j]
    wsmooth[j] = interpsinc(w,tnow[i], over)
    k
step(tnow, w[tnow])
plot(tnow, wsmooth, "r")

---------------------------------------------------------------------------
IndexError                                Traceback (most recent call last)
<ipython-input-2-e925738fd775> in <module>()
     14 for j in range(len(tnow)):
     15     i = tnow[j]
---> 16     wsmooth[j] = interpsinc(w,tnow[i], over)
     17 
     18 step(tnow, w[tnow])

IndexError: index 1000 is out of bounds for axis 0 with size 50
In []: 
def SRRC(syms, beta, P, t_off):
        # syms is 1/2 the length of SRRC pulse in symbol durations
        # beta is the rolloff factor (beta=0 gives sinc)
        # 'P' is the oversampling factor
        # t_off is the phase (or timing) offsets

        
        pass
    
def SRRC2(t, T, beta):
    # Taken from (11.8) on p225
    if t == 0:
        return 1/sqrt(T)*(1-beta+4*beta/pi)
    
    T4b = T/(4.0*beta)
    
    if t == T4b or t == -T4b:
        return (beta/sqrt(2.0*T))*( (1+2/pi)*sin(pi/(4*beta))  + (1-2/pi)* cos(pi/(4*beta)))
    
    ptT = pi*t/T
    t4bT = 4.0*beta*t/T
    
    return 1/sqrt(T) * sin((1-beta)*ptT) + t4bT*cos((1+beta)*ptT)/( (ptT*(1-t4bT*t4bT)))


def interpsinc(x,t,l,beta=0):
    tnow = round(t)
    tau = t-round(t)
    s_tau = SRRC(l,beta,1,tau)
    x_tau = conv(x[tnow-1:tnow+1], s_tau)
    y = x_tau[2*l+1]
    return y