nwcommands/nwbetween.ado at master · Driclit/nwcommands · GitHub

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
*! Date        : 19sept2014
*! Version     : 1.0
*! Author      : Thomas Grund, Linköping University
*! Email	   : contact@nwcommands.org

/////////////////////////////////
//
// Algorithm from Brandes (2001), Journal of Mathematical Sociology
// Implementation builds on Mata code from Modesto Escobar, 2014
//
/////////////////////////////////

capture program drop nwbetween
program nwbetween
	syntax [anything(name=netname)], [GENerate(string) nosym standardize outputoff]
	_nwsyntax `netname', max(9999)
	_nwsetobs

	if `networks' > 1 {
		local k = 1
	}

	local generate_all ""

	foreach netname_temp in `netname' {
		nwtomata `netname_temp', mat(betweennet)
		if "`sym'" != "" {
			mata: betweennet = betweennet :+ betweennet'
		}

		if "`sym'" == "" {
			mata: betweennet = betweennet :/ betweennet
			mata: _editmissing(betweennet, 0)
		}

		mata: C = between(betweennet)
		if "`sym'" != ""  {
			mata: C = C:/2
		}

		if "`generate'" == "" {
			local generate "_between"
		}


		if "`outputoff'" == "" {

		local generate_all "`generate_all' `generate'`k'"
		capture drop `generate'`k'
		nwtostata, mat(C) gen(`generate'`k')
		mata: mata drop betweennet
		qui nwname `netname_temp'
		if "`standardize'" != "" {
			if "`r(directed)'" == "true" {
				qui replace `generate'`k'  = `generate'`k'  / ((`nodes' - 1) * (`nodes' - 2))
			}
			else {
				qui replace `generate'`k'   = `generate'`k'  / ((`nodes' - 1) * (`nodes' - 2) / 2)
			}
		}
		}
		local k = `k' + 1
	}
	mata: st_rclear()


	di "{hline 40}"
	di "{txt}  Network name: {res}`netname'"
	di "{hline 40}"
	di "{txt}    Betweenness centrality"
	if "`standardize'" != "" {
		di "{txt}    (standardized)"
	}
	if "`outputoff'" == "" {
		sum `generate_all'
	}
	mata: st_numscalar("r(bw_central)", sum(J(`nodes',1,max(C)) :- C) / ((`nodes' - 2) * (`nodes' - 1) * (`nodes' - 1)))
	mata: mata drop C
end


/////////////////////////////////
//
// Algorithm from Brandes (2001), Journal of Mathematical Sociology
// Implementation builds on Mata code from Modesto Escobar, 2014
//
/////////////////////////////////

capture mata: mata drop between()
capture mata: mata drop dequeue()

mata:

real scalar function dequeue(real vector Queue)
{
	qvalue=Queue[1]
	for (q=1; q<cols(Queue); q++) {
		Queue[q]=Queue[q+1]
	}
	if(cols(Queue)==1) {
		Queue=J(1,0,.)
	}
	else {
		Queue=Queue[1..cols(Queue)-1]
	}
	return(qvalue)
}

real vector between(real matrix net){

	adjacencyList=J(rows(net),rows(net)-1,.)
	for (m=1; m<=rows(net); m++) {
		k=1
		for (n=1; n<=rows(net); n++) {
			if ( m!=n & net[m,n]>0) adjacencyList[m,k++]=n
		}
    }

	Cb=J(1,rows(net),0)
	for(s=1; s<=rows(net); s++) {
		Stack=J(1,0,.)
		P=J(rows(net),rows(net),.)
		nP=J(rows(net),1,1)
		S=J(1,rows(net),0)
		S[s]=1
		D=J(1,rows(net),-1)
		D[s]=0
		Queue=J(1,0,.)
		Queue=(cols(Queue)? Queue,s : s)

		while(cols(Queue)) {
			v=dequeue(Queue)

			Stack=cols(Stack)? v,Stack : v
			for(j=1; j<=sum(adjacencyList[v,.]:<.);j++) {
				w=adjacencyList[v,j]
				if(D[w]<0) {
					Queue=(cols(Queue)? Queue,w : w)
					D[w]=D[v]+1
				}
				if(D[w]==D[v]+1) {
					S[w]=S[w]+S[v]
					P[w,nP[w]]=v; nP[w]=nP[w]+1
				}
			}
		}

		Dd=J(1,rows(net),0)

		while (cols(Stack)) {
			w=dequeue(Stack)

			for(j=1; j<nP[w]; j++) {
				v=P[w,j]
				Dd[v]=Dd[v]+(S[v]/S[w])*(1+Dd[w])
			}
			if (w!=s) Cb[w]=Cb[w]+Dd[w]
		}
	}
	return(Cb')
}
end
*! v1.5.0 __ 17 Sep 2015 __ 13:09:53
*! v1.5.1 __ 17 Sep 2015 __ 14:54:23