Python how to plot graph sine wave

Question

I have this signal :

from math import*
Fs=8000
f=500
sample=16
a=[0]*sample
for n in range(sample):
    a[n]=sin(2*pi*f*n/Fs)

How can I plot a

Answer 1

The window of usefulness has likely come and gone, but I was working at a similar problem. Here is my attempt at plotting sine using the turtle module.

from turtle import *
from math import *

#init turtle
T=Turtle()

#sample size
T.screen.setworldcoordinates(-1,-1,1,1) 

#speed up the turtle
T.speed(-1)

#range of hundredths from -1 to 1
xcoords=map(lambda x: x/100.0,xrange(-100,101))

#setup the origin
T.pu();T.goto(-1,0);T.pd()

#move turtle
for x in xcoords:
    T.goto(x,sin(xcoords.index(x)))

Answer 2

This is another option

#!/usr/bin/env python

import numpy as np
import matplotlib
matplotlib.use('TKAgg') #use matplotlib backend TkAgg (optional)
import matplotlib.pyplot as plt

sample_rate = 200 # sampling frequency in Hz (atleast 2 times f)
t = np.linspace(0,5,sample_rate)    #time axis
f = 100 #Signal frequency in Hz
sig = np.sin(2*np.pi*f*(t/sample_rate))
plt.plot(t,sig)
plt.xlabel("Time")
plt.ylabel("Amplitude")
plt.tight_layout() 
plt.show()

Answer 3

import matplotlib.pyplot as plt # For ploting
import numpy as np # to work with numerical data efficiently

fs = 100 # sample rate 
f = 2 # the frequency of the signal

x = np.arange(fs) # the points on the x axis for plotting
# compute the value (amplitude) of the sin wave at the for each sample
y = np.sin(2*np.pi*f * (x/fs)) 

#this instruction can only be used with IPython Notbook. 
% matplotlib inline
# showing the exact location of the smaples
plt.stem(x,y, 'r', )
plt.plot(x,y)