This sample demonstrates how point clustering can be used to group points into clusters based on their spatial proximity to one another. Clustering is enabled on the layer's featureReduction property.
Since featureReduction
is independent of the renderer, the symbol and popupTemplate
of each cluster graphic can be used to summarize features within the cluster. See Clustering styles and configurations for more information about the various ways clusters can summarize the points they represent.
The layer's renderer in this sample visualizes weather data with three visual variables, each representing a different attribute:
- Color:
TEMP
- Size:
WIND_SPEED
- Rotation:
WIND_DIRECT
The renderer object looks like the the following:
Calculate cluster statistics
Use dark colors for code blocksCopy 46
46
46
46
46
46
46
46
46
46
46
46
46
46
46
46
46
46
46
46
46
46
46
46
46
46
46
46
46
46
46
46
46
46
46
46
46
46
46
46
46
46
46
46
46
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
99
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
const renderer = {
type: "simple", // autocasts as new SimpleRenderer()
symbol: {
type: "simple-marker", // autocasts as new SimpleMarkerSymbol()
// Arrow marker
path: "M14.5,29 23.5,0 14.5,9 5.5,0z",
color: [50, 50, 50],
outline: {
color: [0, 0, 0, 0.7],
width: 0.5
},
angle: 180,
size: 15
},
visualVariables: [
{
type: "rotation",
// Use {cluster_avg_WIND_DIRECT} in the
// featureReudction.popupTemplate to
// display the average temperature of all
// features within the cluster
field: "WIND_DIRECT",
rotationType: "geographic"
},
{
type: "size",
// Use {cluster_avg_WIND_SPEED} in the
// featureReudction.popupTemplate to
// display the average temperature of all
// features within the cluster
field: "WIND_SPEED",
minDataValue: 0,
maxDataValue: 60,
minSize: 8,
maxSize: 40
},
{
type: "color",
// Use {cluster_avg_TEMP} in the
// featureReudction.popupTemplate to
// display the average temperature of all
// features within the cluster
field: "TEMP",
stops: [
{ value: 20, color: "#2b83ba" },
{ value: 35, color: "#abdda4" },
{ value: 50, color: "#ffffbf" },
{ value: 65, color: "#fdae61" },
{ value: 80, color: "#d7191c" }
]
}
]
};
To enable clustering on the layer, you simply have to set the featureReduction
property to type cluster
,
Use dark colors for code blocksCopy
1
2
3
layer.featureReduction = {
type: "cluster"
};
This will cluster the points using the default clusterRadius
(80px), and assign a symbol to each cluster conforming to the visualVariables
in the renderer in the following manner:
- Color: average
TEMP
of all features in the cluster - Size: average
WIND_SPEED
of all features in the cluster - Rotation: average
WIND_DIRECT
of all features in the cluster
No feature reduction | Clustered features |
---|
|
) |
If a UniqueValueRenderer were used, the symbol of the predominant uniqueValueInfo
among the features in the cluster would be used to represent the cluster.
To provide more meaning to the app, you can configure a popupTemplate to display the average values of all the fields used by the renderer when the user clicks or taps the cluster.
Configure clustering based on renderer
Use dark colors for code blocksCopy 107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
137
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
const clusterConfig = {
type: "cluster",
popupTemplate: {
content: [{
type: "text",
text: "This cluster represents <b>{cluster_count}</b> weather stations."
}, {
type: "fields",
fieldInfos: [{
fieldName: "cluster_avg_WIND_SPEED",
label: "Average wind speed (km/h)",
format: {
places: 0
}
}, {
fieldName: "cluster_avg_WIND_DIRECT",
label: "Average wind direction (degrees)",
format: {
places: 0
}
}, {
fieldName: "cluster_avg_TEMP",
label: "Average temperature (°F)",
format: {
places: 0
}
}]
}]
}
};