Why there is no any input of the picture?

[Tony]

I have to use the module matplotlib to plot a scatter graph on the map.
here is my codes

def map_of_sighting(altas_data):
    """this function is used to iterate through the data and extract
    the values of latitude and longtitude from each sighting,then these values
     will be ploted on the map"""

    starting_index = 1
    latitude = []
    longtitude = []
    while starting_index < len(altas_data):
        latitude.append(altas_data[i][0])
        longtitude.append(altas_data[i][1])
        i=i+1
    plt.imshow(mpimg.imread('map.png'),extent = [149.105, 149.130, -35.29, -35.27])
    plt.scatter(latitude, longtitude)
    plt.show()

it can be run, however, there is no any input of picture, i ran my codes in Pycharm and Jupyter notebook, it was the same situation.I am grateful for any help. Thanks in advance.

[buran]

This is just a function definition.It will mot produce any result unless you call it. Note that you need to pass some data when calling it (that is atlas_data)

[Tony]

This is just a function definition.It will mot produce any result unless you call it. Note that you need to pass some data when calling it (that is atlas_data)

I had modified my function and also called the functions,i still have two major issues.
1.If i put plt.show under plt.imshow and plt.scatter respectively, two diagrams outputted are what I want, however If i only put pat.show there, the scatter dot become only one dot. i tried, but there is no way to get rid of this issue.

2.if i put my extent argument in imshow function, the background picture which is a map will disappear,why is it so? I really have no idea.

here is my codes

def map_of_sighting(altas_data):
    """this function is used to iterate through the data and extract
    the values of latitude and longtitude from each sighting,then these values
     will be ploted on the map"""

    starting_index = 1
    latitude = []
    longtitude = []
    while starting_index < len(altas_data):
        float_latitude = float(altas_data[starting_index][1])
        latitude.append(float_latitude)
        float_longtitude = float(altas_data[starting_index][2])
        longtitude.append(float_longtitude)
        starting_index = starting_index + 1
    plt.imshow(mpimg.imread('map.png'),extent = (149.105, 149.130, -35.29, -35.27) )
    #plt.show()
    plt.scatter(latitude, longtitude)
    #plt.show()
    plt.show()

map_of_sighting(altas_data)