for cur_col in range(start_col, total_col):
    y_data = [file_data[i, cur_col] for i in range(len(file_data)) if not 
        file_data[i, cur_col] in nan_values]
x_data = [file_data[i, time_col] for i in range(len(file_data)) if not 
    file_data[i, cur_col] in nan_values]
Creating a masked array in Python with multiple given values