human
I am working on the file "DL0110EN/2.2.1linear_regression_one_parameter_v2.ipynb".
The first task is:
The class <code>plot_diagram</code> helps us to visualize the data space and the parameter space during training and has nothing to do with PyTorch.
Can you write Python program for it?

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Give me a the Python program you requested?
assistant
#Here is the Python program you requested.

# The class for plotting

class plot_diagram():
    
    # Constructor
    def __init__(self, X, Y, w, stop, go = False):
        start = w.data
        self.error = []
        self.parameter = []
        self.X = X.numpy()
        self.Y = Y.numpy()
        self.parameter_values = torch.arange(start, stop)
        self.Loss_function = [criterion(forward(X), Y) for w.data in self.parameter_values] 
        w.data = start
        
    # Executor
    def __call__(self, Yhat, w, error, n):
        self.error.append(error)
        self.parameter.append(w.data)
        plt.subplot(212)
        plt.plot(self.X, Yhat.detach().numpy())
        plt.plot(self.X, self.Y,'ro')
        plt.xlabel("A")
        plt.ylim(-20, 20)
        plt.subplot(211)
        plt.title("Data Space (top) Estimated Line (bottom) Iteration " + str(n))
        plt.plot(self.parameter_values.numpy(), self.Loss_function)   
        plt.plot(self.parameter, self.error, 'ro')
        plt.xlabel("B")
        plt.figure()
    
    # Destructor
    def __del__(self):
        plt.close('all')