Printing zip lists whose data comes from input user in a loop

Question

Printing zip lists whose data comes from input user in a loop I have made a program that calculates area and perimeter based on 2D coordinates (latitude and latitude) given by the user, asking if they want to include more coordinates from the third pair, and evaluating the area and perimeter each time a pair of coordinates are added.

Besides, it compares the values of the area and perimeter from different regions, choosing how many regions the user want to evaluate.

from pyproj import Geod
geod = Geod(ellps='WGS84')
regions = 0
area_list = []
perimeter_list = []
while True:
 regions += 1
 lats = []
 lons = []
 count = 0
 while True:
 count += 1
 lat = float(input(f"Enter latitude #{count}: "))
 lon = float(input(f"Enter longitude #{count}: "))
 lats.append(lat)
 lons.append(lon)
 
 if count < 3:
 print("Not enough information to calculate the area.")
 continue
 
 poly_area, poly_perimeter = geod.polygon_area_perimeter(lons, lats)
 print(f"Área #{regions}:", (abs(float(poly_area))) / (1000000), "km^2")
 print(f"Perímetro #{regions}:", (abs(float(poly_perimeter))) / (1000), "km")
 if input('Enter more coordinates? [Y/N] ') in ['n', 'N', 'No', 'no', 'non']:
 area_list.append(poly_area)
 perimeter_list.append(poly_perimeter)
# p1 = Polygon([lat lon])
 break 
 if input('More regions? [Y/N] ') in ['n', 'N', 'No', 'no', 'non']:
 break 
while True:
 dividend = int(input(f"Write what region is the dividend:")) - 1
 area_km_dividend = (abs(area_list[dividend])/1000000)
 perimeter_km_dividend = (abs(perimeter_list[dividend])/1000)
 print(f"Area: {area_km_dividend}")
 print(f"Perimeter: {perimeter_km_dividend}")
 
 divisor = int(input(f"Which region is the divisor?:")) - 1
 area_km_divisor = (abs(area_list[divisor])/1000000)
 perimeter_km_divisor = (abs(perimeter_list[divisor])/1000)
 print(f"Area: {area_km_divisor}")
 print(f"Perimeter: {perimeter_km_divisor}")
 
 area_divid_div = area_km_dividend / area_km_divisor
 area_div_divid = area_km_divisor / area_km_dividend
 
 perimeter_divid_div = perimeter_km_dividend / perimeter_km_divisor
 perimeter_div_divid = perimeter_km_divisor / perimeter_km_dividend
 
 if area_divid_div > 1:
 print(f"\nArea of region #{dividend + 1} is", area_divid_div*100 - 100, f"% larger than #{divisor + 1}")
 if perimeter_divid_div > 1:
 print(f"Perimeter of region #{dividend + 1} is", perimeter_divid_div*100 - 100, f"% larger than #{divisor + 1}")
 else:
 print(f"Perimeter of region #{divisor + 1} es un", perimeter_div_divid*100 - 100, f"% larger than #{dividend + 1}")
 else:
 print(f"\nArea of region #{divisor + 1} is", (area_div_divid*100) - 100, f"% larger than #{dividend + 1}")
 if perimeter_divid_div > 1:
 print(f"Perimeter of region #{dividend + 1} is", perimeter_divid_div*100 - 100, f"% larger than #{divisor + 1}")
 else:
 print(f"Perimeter of region #{divisor + 1} is", perimeter_div_divid*100 - 100, f"% larger than #{dividend + 1}")
 
 if input('Do you want to evaluate more regions? [Y/N] ') in ['n', 'N', 'No', 'no', 'non']:
 break

To know if the regions evaluated intercepts, and what percentage of the surface they do, I have added a zip that "joins" each latitude to its longitude value, and I have converted that zip in a list, so I can print it each time because it is in a loop (that calculates the number of areas the user wants):

from pyproj import Geod
geod = Geod(ellps='WGS84')
regions = 0
area_list = []
perimeter_list = []
pair_coordinates_list = [] #NEW
while True:
 regions += 1
 lats = []
 lons = []
 count = 0
 while True:
 count += 1
 lat = float(input(f"Enter latitude #{count}: "))
 lon = float(input(f"Enter longitude #{count}: "))
 lats.append(lat)
 lons.append(lon)
 
 if count < 3:
 print("Not enough information to calculate the area.")
 continue
 
 poly_area, poly_perimeter = geod.polygon_area_perimeter(lons, lats)
#NEW UNTIL...
 print(f"\nLatitude coordinates #{regions}: {lats}")
 print(f"Longitude coordinates #{regions}: {lons}")
 
 pair_coordinates = zip(lats,lons)
 type(pair_coordinates)
 pair_coordinates_list = list(pair_coordinates)
 print(f"Pair of coordinates #{regions}: ", pair_coordinates_list)
 
 for info in zip(lats,lons):
 print(info)
#....HERE
 print(f"Area #{regions}:", (abs(float(poly_area))) / (1000000), "km^2")
 print(f"Perimeter #{regions}:", (abs(float(poly_perimeter))) / (1000), "km")
 if input('Enter more coordinates? [Y/N] ') in ['n', 'N', 'No', 'no', 'non']:
 area_list.append(poly_area)
 perimeter_list.append(poly_perimeter)
# p1 = Polygon([lat lon])
 break 
 if input('More regions? [Y/N] ') in ['n', 'N', 'No', 'no', 'non']:
 break 
while True:
 dividend = int(input(f"Write what region is the dividend:")) - 1
 area_km_dividend = (abs(area_list[dividend])/1000000)
 perimeter_km_dividend = (abs(perimeter_list[dividend])/1000)
 print(f"Area: {area_km_dividend}")
 print(f"Perimeter: {perimeter_km_dividend}")
 print(f"Pair of coordinates of region #{dividend + 1}: ", list(pair_coordinates_list)) #NEW
 
 divisor = int(input(f"Which region is the divisor?:")) - 1
 area_km_divisor = (abs(area_list[divisor])/1000000)
 perimeter_km_divisor = (abs(perimeter_list[divisor])/1000)
 print(f"Area: {area_km_divisor}")
 print(f"Perimeter: {perimeter_km_divisor}")
 print(f"Pair of coordinates of region #{divisor + 1}: ", list(pair_coordinates_list)) #NEW
 
 
 area_divid_div = area_km_dividend / area_km_divisor
 area_div_divid = area_km_divisor / area_km_dividend
 
 perimeter_divid_div = perimeter_km_dividend / perimeter_km_divisor
 perimeter_div_divid = perimeter_km_divisor / perimeter_km_dividend
 
 if area_divid_div > 1:
 print(f"\nArea of region #{dividend + 1} is", area_divid_div*100 - 100, f"% larger than #{divisor + 1}")
 if perimeter_divid_div > 1:
 print(f"Perimeter of region #{dividend + 1} is", perimeter_divid_div*100 - 100, f"% larger than #{divisor + 1}")
 else:
 print(f"Perimeter of region #{divisor + 1} es un", perimeter_div_divid*100 - 100, f"% larger than #{dividend + 1}")
 else:
 print(f"\nArea of region #{divisor + 1} is", (area_div_divid*100) - 100, f"% larger than #{dividend + 1}")
 if perimeter_divid_div > 1:
 print(f"Perimeter of region #{dividend + 1} is", perimeter_divid_div*100 - 100, f"% larger than #{divisor + 1}")
 else:
 print(f"Perimeter of region #{divisor + 1} is", perimeter_div_divid*100 - 100, f"% larger than #{dividend + 1}")
 
 if input('Do you want to evaluate more regions? [Y/N] ') in ['n', 'N', 'No', 'no', 'non']:
 break

For the first loop, it prints correctly each area, but when I call the pair_coordinates_list, it just prints the last list of a pair of coordinates calculated, for any number of regions evaluated.

It goes like this:

Enter latitude #1: 7
Enter longitude #1: 1
Not enough information to calculate the area.
Enter latitude #2: 8
Enter longitude #2: 4
Not enough information to calculate the area.
Enter latitude #3: 9
Enter longitude #3: 1
Latitude coordinates #1: [7.0, 8.0, 9.0]
Longitude coordinates #1: [1.0, 4.0, 1.0]
Pair of coordinates #1: [(7.0, 1.0), (8.0, 4.0), (9.0, 1.0)]
(7.0, 1.0)
(8.0, 4.0)
(9.0, 1.0)
Area #1: 36586.21308722247 km^2
Perimeter #1: 918.6214017289213 km
Enter more coordinates? [Y/N] n
More regions? [Y/N] 3
Enter latitude #1: 4
Enter longitude #1: 8
Not enough information to calculate the area.
Enter latitude #2: 7
Enter longitude #2: 4
Not enough information to calculate the area.
Enter latitude #3: 6
Enter longitude #3: -8
Latitude coordinates #2: [4.0, 7.0, 6.0]
Longitude coordinates #2: [8.0, 4.0, -8.0]
Pair of coordinates #2: [(4.0, 8.0), (7.0, 4.0), (6.0, -8.0)]
(4.0, 8.0)
(7.0, 4.0)
(6.0, -8.0)
Area #2: 242137.74313303368 km^2
Perimeter #2: 3673.4333319086 km
Enter more coordinates? [Y/N] y
Enter latitude #4: 1
Enter longitude #4: 0
Latitude coordinates #2: [4.0, 7.0, 6.0, 1.0]
Longitude coordinates #2: [8.0, 4.0, -8.0, 0.0]
Pair of coordinates #2: [(4.0, 8.0), (7.0, 4.0), (6.0, -8.0), (1.0, 0.0)]
(4.0, 8.0)
(7.0, 4.0)
(6.0, -8.0)
(1.0, 0.0)
Area #2: 640301.386532112 km^2
Perimeter #2: 3881.491201974232 km
Enter more coordinates? [Y/N] n
More regions? [Y/N] n
Write what region is the dividend:2
Area: 640301.386532112
Perimeter: 3881.491201974232
Pair of coordinates of region #2: [(4.0, 8.0), (7.0, 4.0), (6.0, -8.0), (1.0, 0.0)]
Which region is the divisor?:1
Area: 36586.21308722247
Perimeter: 918.6214017289213
Pair of coordinates of region #1: [(4.0, 8.0), (7.0, 4.0), (6.0, -8.0), (1.0, 0.0)]
Area of region #2 is 1650.1165944822358 % larger than #1
Perimeter of region #2 is 322.5343753878306 % larger than #1
Do you want to evaluate more regions? [Y/N] n

"Pair of coordinates of region" line is the same for region #2 and #1, because it takes the last value from that list, which is the second area.

How can I solve it?

Answer 1

You assign zip(lats,lons) to pair_coordinates in every loop. Therefore, when you exit out of the loop, pair_coordinates and pair_coordinates_list always contain the coordinates of the last region you entered.

To solve this, define pair_coordinates_list as a dictionary.

pair_coordinates_list = {}

Then change all pair_coordinates_list as follows, respectively:

line 33 pair_coordinates_list[regions-1] = list(pair_coordinates)
line 34 print(f"Pair of coordinates #{regions}: ", pair_coordinates_list[regions-1])
 ...
line 55 print(f"Pair of coordinates of region #{dividend + 1}: ", list(pair_coordinates_list[dividend]))
 ...
line 62 print(f"Pair of coordinates of region #{divisor + 1}: ", list(pair_coordinates_list[divisor]))

• Tyler Welsh: Massive thanks to Kadir, I was stuck for a lot of hours. Won't forget the "dictionary" definition.