1
00:00:00,000 --> 00:00:02,278
Great, well, we're able to build this

2
00:00:02,279 --> 00:00:04,529
map in the previous lecture. So we have

3
00:00:04,529 --> 00:00:07,193
a base map and we have a marker feature here.

4
00:00:08,123 --> 00:00:10,739
Now, this is our code. Now in this

5
00:00:10,739 --> 00:00:11,879
lecture, I'll show you how to add

6
00:00:11,879 --> 00:00:14,334
multiple markers to your map.

7
00:00:15,248 --> 00:00:19,474
And the way to do that is to, one of the ways to

8
00:00:19,499 --> 00:00:21,959
do that is to write this expression

9
00:00:21,959 --> 00:00:26,053
multiple times. So like that, and of course, you

10
00:00:26,054 --> 00:00:29,576
need to change the locations of those markers.

11
00:00:29,577 --> 00:00:31,746
[No audio]

12
00:00:31,748 --> 00:00:35,436
Save the script and execute,

13
00:00:35,437 --> 00:00:37,621
[No audio]

14
00:00:37,623 --> 00:00:40,527
reload, and so you have multiple markers.

15
00:00:41,045 --> 00:00:43,499
So I think as you realize it's

16
00:00:43,499 --> 00:00:46,139
not possible to add multiple markers

17
00:00:46,529 --> 00:00:50,729
with one single method. So with one

18
00:00:50,729 --> 00:00:52,829
single marker method, you need to apply

19
00:00:52,829 --> 00:00:55,589
the method multiple times. However, this

20
00:00:55,589 --> 00:00:59,219
is not very smart to do, and that's the

21
00:00:59,219 --> 00:01:01,491
beauty of programming, you can use a

22
00:01:01,493 --> 00:01:05,459
for loop to actually add multiple markers to

23
00:01:05,489 --> 00:01:09,149
the map. So we're talking about the Python

24
00:01:09,149 --> 00:01:11,459
for loop, which is a one of the

25
00:01:11,459 --> 00:01:13,919
fundamental features of Python. So the

26
00:01:13,919 --> 00:01:15,749
for loop has nothing to do with folium.

27
00:01:16,949 --> 00:01:18,282
Let's say for

28
00:01:18,283 --> 00:01:21,155
[No audio]

29
00:01:21,157 --> 00:01:24,553
for coordinates in,

30
00:01:24,554 --> 00:01:26,602
[No audio]

31
00:01:26,604 --> 00:01:28,379
of course, you would need some sort of

32
00:01:28,409 --> 00:01:31,919
input with the coordinates. I don't

33
00:01:31,919 --> 00:01:35,459
know, let's say like that, let's say a

34
00:01:35,459 --> 00:01:39,119
list of lists. So we have these two

35
00:01:39,119 --> 00:01:41,928
coordinates. Let me copy this,

36
00:01:41,929 --> 00:01:44,387
[No audio]

37
00:01:44,389 --> 00:01:48,269
put it there, and another time and let me

38
00:01:48,269 --> 00:01:52,820
change them to 9, and 7,

39
00:01:52,821 --> 00:01:57,536
[No audio]

40
00:01:57,538 --> 00:02:01,289
and then you'd need to indent this with four

41
00:02:01,385 --> 00:02:04,748
whitespaces. I'll explain this in just a bit.

42
00:02:04,773 --> 00:02:06,891
[No audio]

43
00:02:06,893 --> 00:02:11,443
And in location, you'd need to pass coordinates.

44
00:02:11,444 --> 00:02:14,457
[No audio]

45
00:02:14,459 --> 00:02:17,154
Before explaining the code to you, let me try this alt.

46
00:02:19,077 --> 00:02:25,815
Execute, go to reload, and yep, we still

47
00:02:25,816 --> 00:02:28,229
have the markers there. Of course, the location

48
00:02:28,229 --> 00:02:30,539
changed from the previous one because I

49
00:02:30,539 --> 00:02:33,419
changed the coordinates, here and here.

50
00:02:34,169 --> 00:02:36,539
So how is this working? Well, I'm

51
00:02:36,569 --> 00:02:39,239
iterating with a for loop through this

52
00:02:39,269 --> 00:02:43,259
list of lists. So the items obviously,

53
00:02:43,829 --> 00:02:46,919
of this main list or two other lists,

54
00:02:47,129 --> 00:02:48,809
something items can be anything, in this

55
00:02:48,809 --> 00:02:50,399
case, there are two lists. So what

56
00:02:50,399 --> 00:02:52,079
happens is that, the coordinates

57
00:02:52,109 --> 00:02:54,659
variable in the first iteration, it

58
00:02:54,659 --> 00:02:58,259
will get this first item of the list,

59
00:02:58,649 --> 00:03:04,199
and it will put that small list. So 38.2

60
00:03:04,229 --> 00:03:08,518
-99.1, if you put that list in here.

61
00:03:08,519 --> 00:03:10,840
[No audio]

62
00:03:10,842 --> 00:03:13,589
So basically, this will be

63
00:03:13,589 --> 00:03:17,369
put in here, more or less. That's the

64
00:03:17,369 --> 00:03:20,339
idea. And then in the next iteration

65
00:03:20,399 --> 00:03:22,469
coordinates with fetch, these are the

66
00:03:22,469 --> 00:03:24,299
list and it will put it in here again.

67
00:03:24,929 --> 00:03:28,049
So the marker method will be executed

68
00:03:28,049 --> 00:03:30,749
two times. So the first time it will

69
00:03:30,749 --> 00:03:34,169
generate a marker with this coordinates,

70
00:03:34,169 --> 00:03:35,519
and then in the second iterate

71
00:03:35,549 --> 00:03:37,469
iteration, it will generate a marker

72
00:03:37,469 --> 00:03:39,449
with this coordinates. And that's it.

73
00:03:39,989 --> 00:03:42,149
However, we have a small issue here, the

74
00:03:42,149 --> 00:03:45,359
issue is that, you know, in reality, you

75
00:03:45,599 --> 00:03:48,149
cannot just type the coordinates in a

76
00:03:48,149 --> 00:03:50,669
Python list. Let's say you have 1000

77
00:03:50,699 --> 00:03:53,189
coordinates that you need to map into a

78
00:03:53,189 --> 00:03:57,209
map. And you can, and it's hard to type

79
00:03:57,209 --> 00:04:00,839
them in here or even paste them, copy

80
00:04:00,839 --> 00:04:03,899
and paste them from document in here. So

81
00:04:03,899 --> 00:04:06,839
the solution to that is that, that your

82
00:04:06,839 --> 00:04:08,729
coordinates normally in real life,

83
00:04:08,729 --> 00:04:12,719
they've come as maybe a text file, like

84
00:04:12,719 --> 00:04:16,710
a comma separated text file, CSV, Excel files, etc.

85
00:04:16,711 --> 00:04:18,750
[No audio]

86
00:04:18,752 --> 00:04:20,339
You want to load that file

87
00:04:20,339 --> 00:04:23,249
into Python and then you want to add

88
00:04:23,639 --> 00:04:26,129
the values of that file into the Marker

89
00:04:26,129 --> 00:04:29,609
methods. And you can do that using a for

90
00:04:29,609 --> 00:04:32,039
loop. And how you do that exactly. Well

91
00:04:32,039 --> 00:04:33,959
explain that in the next lecture. Well,

92
00:04:34,319 --> 00:04:36,989
I'll give you a comma separated file

93
00:04:37,019 --> 00:04:39,749
with a lots of coordinates. And we're

94
00:04:39,749 --> 00:04:41,909
going to use that in the script. So I'll

95
00:04:41,909 --> 00:04:43,264
talk to you later.