Implementation of Quantum Random Projection

Question

I want to implement quantum version of Random Projection Dimensionality Reduction Technique on a dataset. Even after using the latest version of Qiskit, it gives the following error:

  Cell In[3], line 59
    main(csv_file, n_features_after_reduction)
  Cell In[3], line 48 in main
    reduced_features = quantum_random_projection(features, n_features_after_reduction)
  Cell In[3], line 21 in quantum_random_projection
    quantum_state = feature_map.encode(features)
AttributeError: 'ZZFeatureMap' object has no attribute 'encode'

The code I am using is:

import numpy as np
from qiskit import QuantumCircuit, transpile, execute, Aer
from qiskit.circuit.library import ZZFeatureMap

def load_dataset(csv_file):
    dataset = pd.read_csv(csv_file)
    labels = dataset.iloc[:, 0].to_numpy()
    features = dataset.iloc[:, 1:].to_numpy()
    return features, labels

def quantum_random_projection(features, n_features):

    feature_map = ZZFeatureMap(feature_dimension=n_features, reps=2, entanglement='linear', insert_barriers=False)
    quantum_state = feature_map.encode(features)
    random_circuit = QuantumCircuit(feature_map.num_qubits)
    random_circuit.h(0)
    random_circuit.cx(0, 1)

    combined_circuit = QuantumCircuit(feature_map.num_qubits)
    combined_circuit.append(quantum_state, 0)
    combined_circuit.append(random_circuit, 0)

    transpiled_circuit = transpile(combined_circuit, Aer.get_backend('statevector_simulator'))
    job = execute(transpiled_circuit, Aer.get_backend('statevector_simulator'), shots=8192)
    result = job.result()
    reduced_data = [result.get_counts(combined_circuit)[key] / 8192 for key in range(2 ** feature_map.num_qubits)]

    return reduced_data

def main(csv_file, n_features_after_reduction):

    features, labels = load_dataset(csv_file)
    reduced_features = quantum_random_projection(features, n_features_after_reduction)
    reduced_dataset = np.column_stack((reduced_features, labels))
    np.savetxt('reduced_dataset.csv', reduced_dataset, delimiter=',', fmt='%s')

if __name__ == "__main__":
    csv_file = 'initial.csv'
    n_features_after_reduction = 10
    main(csv_file, n_features_after_reduction)```

Also I am very new to quantum algorithms and have very little (tending to 0) knowledge about them.

I am using IBM Quantum learning platform to run my code.