Python question clearing graphic variable

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One of the projects in the book was finding the ISS. I added in the Latitude and Longitude along with Astronaut names. How can I clear the variables each time so they can overwrite not copy over the top.

# !/bin/python3


import json
import time
import turtle
import urllib.request

count = 1
while count > 0:


    url = 'http://api.open-notify.org/astros.json'
    response = urllib.request.urlopen(url)
    result = json.loads(response.read())


    url2 = 'http://api.open-notify.org/iss-now.json'
    response2 = urllib.request.urlopen(url2)
    result2 = json.loads(response2.read())
    people = result['people']


    location = result2['iss_position']
    lat = location['latitude']
    lat = float(lat)
    lon = location['longitude']
    lon = float(lon)


    screen = turtle.Screen()
    screen.setup(720, 360)
    screen.setworldcoordinates(-180, -90, 180, 90)
    screen.bgpic('map.gif')


    screen.register_shape('iss.gif')
    iss = turtle.Turtle()
    iss.shape('iss.gif')
    iss.setheading(90)


    iss.speed('fastest')
    iss.penup()
    iss.goto(lon, lat)

    # set marker location for Clinton, Township
    lat_man = 42.58502
    lon_man = -82.916985
    location_man = turtle.Turtle()
    location_man.penup()
    location_man.color('yellow')
    location_man.goto(lon_man, lat_man)
    location_man.dot(5)
    location_man.hideturtle()

    url_man = 'http://api.open-notify.org/iss-pass.json?lat=42.58502&lon=-82.916985'
    response_man = urllib.request.urlopen(url_man)
    result_man = json.loads(response_man.read())
    over_man = result_man['response'][1]['risetime']

    style = ('Arial', 8, 'bold')
    location_man.write(time.ctime(over_man), font=style)

    coor_lon = -42.0
    coor_lat = -170.0
    location_lon = turtle.Turtle()
    location_lon.penup()
    location_lon.color('yellow')
    location_lon.goto(coor_lat, coor_lon)
    location_lon.hideturtle()
    location_lon.speed('fastest')

    style = ('Arial', 8, 'bold')
    location_lon.write('Longitude', font=style)

    coor_lon = -42.0
    coor_lat = -140.0
    location_lon = turtle.Turtle()
    location_lon.penup()
    location_lon.color('yellow')
    location_lon.goto(coor_lat, coor_lon)
    location_lon.hideturtle()

    style = ('Arial', 8, 'bold')
    location_lon.clear()
    location_lon.write(lon, font=style)

    # ISS Latitude
    coor_lon = -49.0
    coor_lat = -170.0
    location_lon = turtle.Turtle()
    location_lon.penup()
    location_lon.color('yellow')
    location_lon.goto(coor_lat, coor_lon)
    location_lon.hideturtle()

    style = ('Arial', 8, 'bold')
    location_lon.write('Latitude', font=style)

    # ISS Longitude
    coor_lon = -49.0
    coor_lat = -140.0

    location_lon = turtle.Turtle()
    location_lon.penup()
    location_lon.color('yellow')
    location_lon.goto(coor_lat, coor_lon)
    location_lon.hideturtle()

    style = ('Arial', 8, 'bold')
    location_lon.write(lat, font=style)

    # people on ISS
    number_on_iss = len(people)
    start_name_lon = -22.0
    for p in people:
        coor_lon = start_name_lon
        coor_lat = 55.0
        location_lon = turtle.Turtle()
        location_lon.penup()
        location_lon.color('yellow')
        location_lon.goto(coor_lat, coor_lon)
        location_lon.hideturtle()

        style = ('Arial', 8, 'bold')
        location_lon.write(p['name'], font=style)
        start_name_lon -= 7

turtle.mainloop()
time.sleep(0.01)

ISS.zip graphics for project

@Michael-McKenney,
Could you point me specifically to the variables that you are referring to? Moreover, I am not sure what you mean by, "so they can overwrite not copy over the top".

In the loop they keep overwriting the lat and lon values. I want to clear them and then write the new one.

location_lon.write('Latitude', font=style)
location_lon.write(lat, font=style)

location_lon.write('Longitude', font=style)
location_lon.write(lon, font=style)

I am going to rewrite it today to change the variable names.

I made the changes to the variable names to make it easier to read.

# !/bin/python3


import json
import time
import turtle
import urllib.request

count = 1
while count > 0:


    url = 'http://api.open-notify.org/astros.json'
    response = urllib.request.urlopen(url)
    result = json.loads(response.read())


    url2 = 'http://api.open-notify.org/iss-now.json'
    response2 = urllib.request.urlopen(url2)
    result2 = json.loads(response2.read())
    people = result['people']


    location = result2['iss_position']
    lat = location['latitude']
    lat = float(lat)
    lon = location['longitude']
    lon = float(lon)


    screen = turtle.Screen()
    screen.setup(720, 360)
    screen.setworldcoordinates(-180, -90, 180, 90)
    screen.bgpic('map.gif')


    screen.register_shape('iss.gif')
    iss = turtle.Turtle()
    iss.shape('iss.gif')
    iss.setheading(90)


    iss.speed('fastest')
    iss.penup()
    iss.goto(lon, lat)

    # set marker location for Clinton, Township
    lat_man = 42.58502
    lon_man = -82.916985
    location_man = turtle.Turtle()
    location_man.penup()
    location_man.color('yellow')
    location_man.goto(lon_man, lat_man)
    location_man.dot(5)
    location_man.hideturtle()

    url_man = 'http://api.open-notify.org/iss-pass.json?lat=42.58502&lon=-82.916985'
    response_man = urllib.request.urlopen(url_man)
    result_man = json.loads(response_man.read())
    over_man = result_man['response'][1]['risetime']

    style = ('Arial', 8, 'bold')
    location_man.write(time.ctime(over_man), font=style)

    coor_lon = -42.0
    coor_lat = -170.0
    location_lon_name = turtle.Turtle()
    location_lon_name.penup()
    location_lon_name.color('yellow')
    location_lon_name.goto(coor_lat, coor_lon)
    location_lon_name.hideturtle()
    location_lon_name.speed('fastest')

    style = ('Arial', 8, 'bold')
    location_lon_name.write('Longitude', font=style)

    coor_lon = -42.0
    coor_lat = -140.0
    location_lon = turtle.Turtle()
    location_lon.penup()
    location_lon.color('yellow')
    location_lon.goto(coor_lat, coor_lon)
    location_lon.hideturtle()
    style = ('Arial', 8, 'bold')
    location_lon.clear()
    location_lon.write(lon, font=style)

    # ISS Latitude
    coor_lon = -49.0
    coor_lat = -170.0
    location_lat_name = turtle.Turtle()
    location_lat_name.penup()
    location_lat_name.color('yellow')
    location_lat_name.goto(coor_lat, coor_lon)
    location_lat_name.hideturtle()
    style = ('Arial', 8, 'bold')
    location_lat_name.write('Latitude', font=style)

    # ISS Longitude
    coor_lon = -49.0
    coor_lat = -140.0

    location_lat = turtle.Turtle()
    location_lat.penup()
    location_lat.color('yellow')
    location_lat.goto(coor_lat, coor_lon)
    location_lat.hideturtle()
    style = ('Arial', 8, 'bold')
    location_lat.write(lat, font=style)

    # people on ISS
    number_on_iss = len(people)
    start_name_lon = -22.0
    for p in people:
        coor_lon = start_name_lon
        coor_lat = 55.0
        people_iss = turtle.Turtle()
        people_iss.penup()
        people_iss.color('yellow')
        people_iss.goto(coor_lat, coor_lon)
        people_iss.hideturtle()

        style = ('Arial', 8, 'bold')
        people_iss.write(p['name'], font=style)
        start_name_lon -= 7

turtle.mainloop()
time.sleep(0.01)

@Michael-McKenney
If I am understanding you correctly, then you would need to either call location_lon_man.clear() or you could try to call turtle.clearscreen(). These are only going to affect the graphical rendering of your program, but not necessarily do anything to the other variables at hand. During each loop, you are reassigning a value to the variables that you are declaring in the scope of the loop. If you want, you could just add one of these method/function calls at the very beginning of the loop.

clearscreen() blanks the entire screen. .clear() doesn't seem to remove the variable before it sends the next value.

I came up with changing the background to blue and then writing yellow over it.

# !/bin/python3


import json
import time
import turtle
import urllib.request

prev_lon = 888.8888
prev_lat = 888.8888


count = 1
while count > 0:
    turtle.reset()
    url = 'http://api.open-notify.org/astros.json'
    response = urllib.request.urlopen(url)
    result = json.loads(response.read())


    url2 = 'http://api.open-notify.org/iss-now.json'
    response2 = urllib.request.urlopen(url2)
    result2 = json.loads(response2.read())
    people = result['people']


    location = result2['iss_position']
    lat = location['latitude']
    lat = float(lat)
    lon = location['longitude']
    lon = float(lon)


    screen = turtle.Screen()
    screen.setup(720, 360)
    screen.setworldcoordinates(-180, -90, 180, 90)
    screen.bgpic('map.gif')


    screen.register_shape('iss.gif')
    iss = turtle.Turtle()
    iss.shape('iss.gif')
    iss.setheading(90)


    iss.speed('fastest')
    iss.penup()
    iss.goto(lon, lat)

    # set marker location for Clinton, Township
    lat_man = 42.58502
    lon_man = -82.916985
    location_man = turtle.Turtle()
    location_man.penup()
    location_man.color('yellow')
    location_man.goto(lon_man, lat_man)
    location_man.dot(5)
    location_man.hideturtle()

    url_man = 'http://api.open-notify.org/iss-pass.json?lat=42.58502&lon=-82.916985'
    response_man = urllib.request.urlopen(url_man)
    result_man = json.loads(response_man.read())
    over_man = result_man['response'][1]['risetime']

    style = ('Arial', 8, 'bold')
    location_man.write(time.ctime(over_man), font=style)

    coor_lon = -42.0
    coor_lat = -170.0
    location_lon_name = turtle.Turtle()
    location_lon_name.penup()
    location_lon_name.color('yellow')
    location_lon_name.goto(coor_lat, coor_lon)
    location_lon_name.hideturtle()
    location_lon_name.speed('fastest')

    style = ('Arial', 8, 'bold')
    location_lon_name.clear()
    location_lon_name.write('Longitude', font=style)

    #change to blue
    coor_lon = -42.0
    coor_lat = -140.0
    location_lon = turtle.Turtle()
    location_lon.penup()
    location_lon.color('blue')
    location_lon.goto(coor_lat, coor_lon)
    location_lon.hideturtle()
    style = ('Arial', 8, 'bold')
    location_lon.clear()
    change_color = prev_lon
    location_lon.write(change_color, font=style)


    coor_lon = -42.0
    coor_lat = -140.0
    location_lon = turtle.Turtle()
    location_lon.penup()
    location_lon.color('yellow')
    location_lon.goto(coor_lat, coor_lon)
    location_lon.hideturtle()
    style = ('Arial', 8, 'bold')
    location_lon.clear()
    location_lon.write(lon, font=style)

    # ISS Latitude
    coor_lon = -49.0
    coor_lat = -170.0
    location_lat_name = turtle.Turtle()
    location_lat_name.penup()
    location_lat_name.color('yellow')
    location_lat_name.goto(coor_lat, coor_lon)
    location_lat_name.hideturtle()
    style = ('Arial', 8, 'bold')
    location_lat_name.clear()
    location_lat_name.write('Latitude', font=style)

    # ISS Longitude
    coor_lon = -49.0
    coor_lat = -140.0
    location_lat = turtle.Turtle()
    location_lat.penup()
    location_lat.color('blue')
    location_lat.goto(coor_lat, coor_lon)
    location_lat.hideturtle()
    style = ('Arial', 8, 'bold')
    change_color = prev_lat
    location_lat.write(change_color, font=style)






    # ISS Longitude
    coor_lon = -49.0
    coor_lat = -140.0
    location_lat = turtle.Turtle()
    location_lat.penup()
    location_lat.color('yellow')
    location_lat.goto(coor_lat, coor_lon)
    location_lat.hideturtle()
    style = ('Arial', 8, 'bold')
    location_lat.clear()
    location_lat.write(lat, font=style)

    # people on ISS
    number_on_iss = len(people)
    start_name_lon = -22.0
    for p in people:
        coor_lon = start_name_lon
        coor_lat = 55.0
        people_iss = turtle.Turtle()
        people_iss.penup()
        people_iss.color('blue')
        people_iss.goto(coor_lat, coor_lon)
        people_iss.hideturtle()
        style = ('Arial', 8, 'bold')
        people_iss.clear()
        people_iss.write(p['name'], font=style)
        start_name_lon -= 7



    # people on ISS
    number_on_iss = len(people)
    start_name_lon = -22.0
    for p in people:
        coor_lon = start_name_lon
        coor_lat = 55.0
        people_iss = turtle.Turtle()
        people_iss.penup()
        people_iss.color('yellow')
        people_iss.goto(coor_lat, coor_lon)
        people_iss.hideturtle()
        style = ('Arial', 8, 'bold')
        people_iss.clear()
        people_iss.write(p['name'], font=style)
        start_name_lon -= 7

        prev_lon = lon
        prev_lat = lat

turtle.mainloop()
time.sleep(0.01)