summaryrefslogtreecommitdiff
path: root/Code/correlation_per_group.R
blob: 65f20c58449e733c6ac0a2553c3f8b0922c418f8 (plain)
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
# Last modified on 9 Aug 2019 by Hui Lan

DATA.FILE      <- '../Data/history/expr/TPM.txt'
TARGET.TF.FILE <- '../Data/information/target_tf.txt'
AGINAME.FILE   <- '../Data/information/AGI-to-gene-names_v2.txt'
r.tau        <- 0.60
min.cluster  <- 3  # min number of clusters


# Make sure we have required files
if (! file.exists(DATA.FILE)) {
   stop(sprintf('[correlation_per_group.R] Unable to find %s', DATA.FILE))
}

if (! file.exists(TARGET.TF.FILE)) {
   stop(sprintf('[correlation_per_group.R] Unable to find %s', TARGET.TF.FILE))
}

if (! file.exists(AGINAME.FILE)) {
   stop(sprintf('[correlation_per_group.R] Unable to find %s', AGINAME.FILE))
}


cat(sprintf('Read %s\n', DATA.FILE))
X             <- read.table(DATA.FILE, header=TRUE, check.names=FALSE)
all.id        <- X$gene_id
X$gene_id     <- NULL   # remove column gene_id
row.names(X)  <- all.id # add row names
all.genes     <- rownames(X)

min.sample   <- max(50, ceiling(sqrt(dim(X)[2]))) # at least this many samples needed for computing a correlation coefficient
max.cluster  <- min(55, max(min.cluster + 1, ceiling(dim(X)[2]^0.50))) # max number of clusters, depending on total number of samples


# Filter genes
rowsum.tau <- dim(X)[2]       # the gene's TPM value is at least 1 on average
sd.val     <- apply(X, 1, sd)
lambda <- 0.3
#sd.tau  <- lambda * summary(sd.val)[3] + (1-lambda) * summary(sd.val)[5] # genes whose gene expression varies least are to be filtered
sd.tau <- 1
index.row <- rowSums(X) > rowsum.tau & sd.val > sd.tau & !is.na(sd.val)

X  <- log(X[index.row, ] + 1.0)

# Normalize each row such that its mean is 0 and standard deviation is 1
normalize <- function(X) {
    d <- dim(X)
    num_row <- d[1]
    num_col <- d[2]
    
    s <- apply(X, 1, sd)
    S <- matrix(rep(s, num_col), nrow=num_row)
    m <- apply(X, 1, mean)
    M <- matrix(rep(m, num_col), nrow=num_row)
    X <- (X - M)/S
}

X2 <- normalize(X)

cat(sprintf('Read %s\n', AGINAME.FILE))
agi        <- read.table(AGINAME.FILE, stringsAsFactors=F) # AGINAME_FILE cannot contain quotes

cat(sprintf('Read %s\n', TARGET.TF.FILE))
target.tf <- read.table(TARGET.TF.FILE, header=FALSE, check.names=FALSE, sep='\t')
total.pair <- dim(target.tf)[1]

cat(sprintf('min.cluster=%d, max.cluster=%d, min.sample=%d, r.tau=%4.2f\n', min.cluster, max.cluster, min.sample, r.tau))
cat('Hclust ...\n')
clusters <- hclust(dist(t(X2)), method = 'average')
cat('Go through pairs..\n')
output.file <- paste('../Data/history/edges/one_target/edges.txt', 'group', format(Sys.time(), '%b.%d.%Y.%H%M%S'), sep='.')
f <- file(output.file, 'w')

for (i in 1:total.pair) {
    
    gene.tf <- as.vector(target.tf[i,2])
    gene.target <- as.vector(target.tf[i,1])
    all.in <- gene.tf %in% all.genes & gene.target %in% all.genes
    if (!all.in) {
        next
    }
    if (!gene.tf %in% rownames(X) || !gene.target %in% rownames(X)) { # make sure both gene.tf and gene.target are in X
        next
    }

    # if too few rnaseq samples, or correlation on all rnaseq samples is good, don't look for group correlation
    x <- as.vector(t(X[gene.tf, ]))
    y <- as.vector(t(X[gene.target, ]))
    index <- x < 0.01 | y < 0.01 # don't include data that is too small
    x.1 <- x[!index]
    y.1 <- y[!index]
    if (length(x.1) < min.sample) {
        next
    } else if (cor(x.1, y.1) >= r.tau) {
        next
    }

    
    name1 <- agi$V2[which(agi$V1 == gene.tf)]
    name2 <- agi$V2[which(agi$V1 == gene.target)]	    

    # initial values
    max.r <- 0.0
    max.n <- 0
    max.samples <- c()

    # cut tree into different number of clusters
    for (cn in seq(min.cluster, max.cluster, 2)) { # cn is number of clusters
        cut <- cutree(clusters, cn)
        sample.names <- names(cut)
        for (c in unique(cut)) { # each cluster
            sample.index <- (cut == c)
            x <- as.vector(t(X[gene.tf, sample.index]))
            y <- as.vector(t(X[gene.target, sample.index]))
            n <- length(x)
            if (n > min.sample & sd(x) > 0.1 & sd(y) > 0.1) { # both x and y should vary
                r <- cor(x, y)
            } else {
                r <- 0.0
            }

            if (n > min.sample & abs(r) > r.tau & n > max.n) {
                max.r <- r
                max.n <- n
                max.samples <- sample.names[sample.index]
            }
        }
    }

    # save results
    if (max.n > 0) {
        curr.date <- gsub('-','',Sys.Date())
        loglik <- '-991.0'
        sub.cond <- paste(max.samples, collapse=' ')
	num.sub.cond <- length(max.samples)
        cond <- as.vector(target.tf[i,3])
        result <- sprintf('%s %s\t%s %s\t%4.2f\t%s\t%s\t%s\t%s\t%s\t%4.2f\t%s\n', gene.target, name2, gene.tf, name1, max.r, 'mix', num.sub.cond, cond, loglik, curr.date, max.r, 'hclust.group')
        cat(result, file=f, sep='')
    }
}

close(f)