#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
Created on Thu Feb 28 11:00:18 2019

@author: oyvind
"""

import numpy as np
import matplotlib.pyplot as plt

def H(f):
    w = 2 * np.pi * f
    
    return (w * 10**(-4))/np.sqrt(1+(w*10**(-4))**2)

frq = []
values = []
for i in range(2*10**5):
    frq.append(i)
    value = 20 * np.log10(abs(H(i)))
    values.append(value)

plt.plot(frq, values)
plt.xscale('log')
plt.gca().xaxis.grid(True)