class Graficos(object):
    def __init__(self):
        self.rango = X
        self.funcion = Y
        self.titulo = t
        if m == 'f1':
            X = np.linspace(-100,100,1000)
            Y = (3*X)/(np.sqrt(X**2))
            t = '(3*X)/(np.sqrt(X**2)'
        if m == 'f2':
            X = np.linspace(-100,100,1000)
            Y = (X+5)
            t = 'X+5'
        if m == 'f3':
            X = np.linspace(1,10,50)
            Y = (np.log (X))/X
            t = 'lnx/x'
        if m == 'f4':
            X = np.linspace(-100,100,1000)
            Y = (X*2)*(np.exp(x**2))
            t = '2x *e(x**2)'
    def histograma (self):
        plt.figure ('histograma')
        plt.title (self.titulo)
        plt.hist(self.funcion,10000, self.rango)
        plt.show ()
if __name__=='__main__':
    m=raw_input('Introduce la función que quieres mostrar: ')
    g=Graficos()
    g.histograma()

  Line 28
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