def cursorAtSpaceEnd(block):
            cursor = QTextCursor(block)
            cursor.setPosition(block.position() + len(blockIndentation(block)))
            return cursor
def __init__(self, data, amount_clusters, means=None, variances=None, observer=None, tolerance=0.00001, iterations=100):
        """!
        @brief Initializes Expectation-Maximization algorithm for cluster analysis.