library(atSNP)
library(testthat)
data(example)
if(.Platform$OS.type == "unix") {
registerDoParallel(4)
} else {
registerDoParallel(cl <- makeCluster(4))
}
trans_mat <- matrix(rep(snpInfo$prior, each = 4), nrow = 4)
id <- 1
test_pwm <- motif_library[[id]]
##test_pwm <- motif_library[["ALX3_jolma_DBD_M449"]]
scores <- as.matrix(motif_scores$motif.scores[motif == names(motif_library)[id], list(log_lik_ref, log_lik_snp)])
motif_len <- nrow(test_pwm)
## these are functions for this test only
drawonesample <- function(theta) {
delta <- snpInfo$prior * t(test_pwm ^ theta)
delta <- delta / rep(apply(delta, 2, sum), each = 4)
sample <- sample(1:4, 2 * motif_len - 1, replace = TRUE, prob = snpInfo$prior)
id <- sample(seq(motif_len), 1)
sample[id : (id + motif_len - 1)] <- apply(delta, 2, function(x) sample(1:4, 1, prob = x))
sc <- s_cond <- 0
for(s in seq(motif_len)) {
sc <- sc + prod(test_pwm[cbind(seq(motif_len),
sample[s : (s + motif_len - 1)])]) ^ theta
}
s_cond <- prod(test_pwm[cbind(seq(motif_len),
sample[id : (id + motif_len - 1)])]) ^ theta
sample <- c(sample, id, sc, s_cond)
return(sample)
}
jointprob <- function(x) prod(test_pwm[cbind(seq(motif_len), x)])
maxjointprob <- function(x) {
maxp <- -Inf
p <- -Inf
for(i in 1:motif_len) {
p <- jointprob(x[i:(i+motif_len - 1)])
if(p > maxp)
maxp <- p
}
for(i in 1:motif_len) {
p <- jointprob(5 - x[(i+motif_len - 1):i])
if(p > maxp)
maxp <- p
}
return(maxp)
}
get_freq <- function(sample) {
ids <- cbind(
rep(sample[motif_len * 2, ], each = motif_len) + seq(motif_len),
rep(seq(1000), each = motif_len))
sample_motif <- matrix(sample[ids], nrow = motif_len) + 1
emp_freq <- matrix(0, nrow = motif_len, ncol = 4)
for(i in seq(motif_len)) {
for(j in seq(4)) {
emp_freq[i, j] <- sum(sample_motif[i, ] == j)
}
}
emp_freq <- emp_freq / apply(emp_freq, 1, sum)
return(emp_freq)
}
test_that("Error: quantile function computing are not equivalent.", {
for(p in c(1, 10, 50, 90, 99) / 100) {
delta <- .Call("test_find_percentile", c(scores), p, package = "atSNP")
delta.r <- -sort(-c(scores))[as.integer(p * length(scores)) + 1]
expect_equal(delta, delta.r)
}
})
test_that("Error: the scores for samples are not equivalent.", {
p <- 0.01
delta <- .Call("test_find_percentile", scores, p, package = "atSNP")
theta <- .Call("test_find_theta", test_pwm, snpInfo$prior, snpInfo$transition, delta, package = "atSNP")
## Use R code to generate a random sample
for(i in seq(10)) {
sample <- drawonesample(theta)
sample_score <- .Call("test_compute_sample_score", test_pwm, sample[seq(2 * motif_len - 1)] - 1, sample[motif_len * 2] - 1, theta, package = "atSNP")
expect_equal(sample[2 * motif_len + 1], sample_score[2])
expect_equal(sample[2 * motif_len + 2], sample_score[3])
}
## Use C code to generate a random sample
for(i in seq(10)) {
delta <- t(test_pwm ^ theta)
delta <- cbind(matrix(
sum(snpInfo$prior * delta[, 1]),
nrow = 4, ncol = motif_len - 1), delta)
sample <- .Call("test_importance_sample", delta, snpInfo$prior, trans_mat, test_pwm, theta, package = "atSNP")
start_pos <- sample[motif_len * 2]
adj_score <- 0
for(s in seq(motif_len) - 1) {
adj_score <- adj_score + prod(test_pwm[cbind(seq(motif_len),
sample[s + seq(motif_len)] + 1)]) ^ theta
}
adj_score_cond <- prod(test_pwm[cbind(seq(motif_len), sample[start_pos + seq(motif_len)] + 1)]) ^ theta
sample_score <- .Call("test_compute_sample_score", test_pwm, sample[seq(2 * motif_len - 1)], sample[motif_len * 2], theta, package = "atSNP")
expect_equal(adj_score, sample_score[2])
expect_equal(adj_score_cond, sample_score[3])
}
})
test_that("Error: compute the normalizing constant.", {
## parameters
p <- 0.01
delta <- .Call("test_find_percentile", scores, p, package = "atSNP")
theta <- .Call("test_find_theta", test_pwm, snpInfo$prior, snpInfo$transition, delta, package = "atSNP")
##
const <- .Call("test_func_delta", test_pwm, snpInfo$prior, trans_mat, theta, package = "atSNP")
const.r <- prod(apply(snpInfo$prior * t(test_pwm) ^ theta, 2, sum)) * motif_len
expect_equal(abs(const - const.r) / const < 1e-5, TRUE)
})
test_that("Error: sample distributions are not expected.", {
## parameters
p <- 0.1
delta <- .Call("test_find_percentile", scores, p, package = "atSNP")
theta <- .Call("test_find_theta", test_pwm, snpInfo$prior, trans_mat, delta, package = "atSNP")
delta <- t(test_pwm ^ theta)
delta <- cbind(matrix(
sum(snpInfo$prior * delta[, 1]),
nrow = 4, ncol = motif_len - 1), delta)
results <- foreach(i = seq(motif_len * 2)) %dopar% {
## generate 1000 samples
sample <- sapply(seq(1000), function(x)
.Call("test_importance_sample",
delta, snpInfo$prior, trans_mat, test_pwm, theta, package = "atSNP"))
emp_freq1 <- get_freq(sample)
target_freq <- test_pwm ^ theta * snpInfo$prior
target_freq <- target_freq / apply(target_freq, 1, sum)
## generate samples in R
sample <- sapply(rep(theta, 1000), drawonesample)
emp_freq2 <- get_freq(sample[seq(2 * motif_len), ] - 1)
max(abs(emp_freq1 - target_freq)) > max(abs(emp_freq2 - target_freq))
}
print(sum(unlist(results)))
print(pbinom(sum(unlist(results)), size = 20, prob = 0.5))
})
test_that("Error: the chosen pvalues should have the smaller variance.", {
.structure <- function(pval_mat) {
id1 <- apply(pval_mat[, c(2, 4)], 1, which.min)
return(cbind(
pval_mat[, c(1, 3)][cbind(seq_along(id1), id1)],
pval_mat[, c(2, 4)][cbind(seq_along(id1), id1)])
)
}
for(p in c(0.01, 0.05, 0.1)) {
theta <- .Call("test_find_theta", test_pwm, snpInfo$prior, trans_mat, quantile(c(scores), 1 - p), package = "atSNP")
p_values <- .Call("test_p_value", test_pwm, snpInfo$prior, snpInfo$transition, c(scores), theta, 1000, package = "atSNP")
p_values_s <- .structure(p_values)
expect_equal(p_values_s[, 2], apply(p_values[, c(2, 4)], 1, min))
}
})
## Visual checks
if(FALSE) {
plot(log(y <- sapply(seq(200) / 100 - 1, function(x)
.Call("test_func_delta", test_pwm, snpInfo$prior, snpInfo$transition, x, package = "atSNP"))))
## test the theta
theta <- .Call("test_find_theta", test_pwm, snpInfo$prior, trans_mat, quantile(c(scores), 0.01), package = "atSNP")
p_values_1 <- .Call("test_p_value", test_pwm, snpInfo$prior, snpInfo$transition, c(scores), theta, 1000, package = "atSNP")
theta <- .Call("test_find_theta", test_pwm, snpInfo$prior, trans_mat, quantile(c(scores), 0.9), package = "atSNP")
p_values_9 <- .Call("test_p_value", test_pwm, snpInfo$prior, snpInfo$transition, c(scores), theta, 1000, package = "atSNP")
theta <- .Call("test_find_theta", test_pwm, snpInfo$prior, trans_mat, quantile(c(scores), 0.99), package = "atSNP")
p_values_99 <- .Call("test_p_value", test_pwm, snpInfo$prior, snpInfo$transition, c(scores), theta, 1000, package = "atSNP")
par(mfrow = c(1, 3))
plot(log(p_values_1[, 1]) ~ c(scores))
plot(log(p_values_9[, 1]) ~ c(scores))
plot(log(p_values_99[, 1]) ~ c(scores))
theta <- .Call("test_find_theta", test_pwm, snpInfo$prior, trans_mat, quantile(c(scores), 0.9), package = "atSNP")
p_values_9 <- .Call("test_p_value", test_pwm, snpInfo$prior, trans_mat, c(scores), theta, 1000, package = "atSNP")
theta <- .Call("test_find_theta", test_pwm, snpInfo$prior, trans_mat, quantile(c(scores), 0.99), package = "atSNP")
p_values_99 <- .Call("test_p_value", test_pwm, snpInfo$prior, trans_mat, c(scores), theta, 1000, package = "atSNP")
pval_test <- function(x) {
delta <- .Call("test_find_percentile", c(scores), x, package = "atSNP")
theta <- .Call("test_find_theta", test_pwm, snpInfo$prior, trans_mat, delta, package = "atSNP")
const <- prod(apply(snpInfo$prior * t(test_pwm) ^ theta, 2, sum)) * motif_len
print(const)
sample <- sapply(rep(theta, 1000), drawonesample)
pr <- apply(sample[seq(2 * motif_len - 1), ], 2, maxjointprob)
wei <- const / sample[2 * motif_len + 1, ]
wei.cond <- const / motif_len / sample[2 * motif_len + 2, ]
print(mean(log(sample[2 * motif_len + 1, ])))
print(mean(log(pr)))
print(mean(wei))
pval <- sapply(c(scores), function(x) sum(wei[log(pr) >= x]) / length(wei))
pval.cond <- sapply(c(scores), function(x) sum(wei.cond[log(pr) >= x]) / length(wei.cond))
return(cbind(pval, pval.cond))
}
pval_99 <- pval_test(0.01)
pval_9 <- pval_test(0.1)
rbind(quantile(pval_9, seq(10) / 200),
quantile(p_values_9[, 1], seq(10) / 200),
quantile(pval_99, seq(10) / 200),
quantile(p_values_99[, 1], seq(10) / 200))
plot(log(pval_99[, 1]), log(p_values_99[, 1]))
abline(0,1)
plot(log(pval_9[, 1]), log(p_values_9[, 1]))
abline(0,1)
plot(log(pval_9[, 2]), log(p_values_9[, 5]))
abline(0,1)
plot(p_values_99[, 2], p_values_99[, 4])
abline(0, 1)
plot(p_values_99[, 6], p_values_99[, 8], ylim = c(0, 0.005))
abline(0, 1)
plot(p_values_99[, 1], p_values_99[, 3])
abline(0, 1)
plot(p_values_99[, 1], p_values_99[, 5], xlim = c(0, 0.001), ylim = c(0, 0.001))
abline(0, 0.1)
test1 <- sapply(seq(1000), function(x) drawonesample(0.01))
test2 <- sapply(seq(1000), function(x) drawonesample(0.15))
hist(log(test1[22, ]) / 0.01)
hist(log(test2[21, ]) / 0.15)
}
if(.Platform$OS.type != "unix") {
stopCluster(cl)
}
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