NNSDR/simulations/simulations_binary.R

148 lines
4.7 KiB
R

#!/usr/bin/env Rscript
library(MAVE)
library(CVarE)
Sys.setenv(TF_CPP_MIN_LOG_LEVEL = "3") # Suppress `tensorflow` notes/warnings
suppressPackageStartupMessages({
library(NNSDR)
})
## Parse script parameters
args <- parse.args(defaults = list(
# Simulation configuration
reps = 100, # Number of replications
dataset = 'B2', # Name ('B' for Binary) of the data set
# Neuronal Net. structure/definitions
hidden_units = 512L,
activation = 'relu',
trainable_reduction = TRUE,
# Neuronal Net. training
epochs = c(100L, 200L), # Number of training epochs for (`OPG`, Refinement)
batch_size = 32L,
initializer = 'fromOPG',
seed = 956294L
))
################################################################################
dataset <- function(name = "M1", n = NULL, p = 20, sd = 0.5, ...) {
name <- toupper(name)
if (nchar(name) == 1) { name <- paste0("M", name) }
if (name == "B1") {
if (missing(n)) { n <- 400 }
if (missing(sd)) { sd <- 1 }
eps <- sqrt(.Machine$double.eps)
B <- diag(1, p, 2)
Z <- matrix(rnorm(2 * n, 0, sd), n, 2)
Y <- sample(c(FALSE, TRUE), n, replace = TRUE)
theta <- rnorm(n, Y * pi, 0.25 * pi)
X <- cbind(
10 * (cos(theta) + 0.75 * (2 * Y - 1)) + Z[, 1],
10 * sin(theta) + Z[, 2],
matrix(rnorm(n * (p - 2), 0, sd), n)
)
} else if (name == "B2") {
if (missing(n)) { n <- 400 }
if (missing(sd)) { sd <- 0.2 }
eps <- sqrt(.Machine$double.eps)
B <- diag(1, p, 2)
X <- matrix(runif(n * p, -2, 2), n, p)
XB <- X %*% B
Y <- (sin(XB[, 1]) / (XB[, 2]^2 + eps) + rnorm(n, 0, sd)) > 0
# } else if (name == "B2") {
# if (missing(n)) { n <- 400 }
# if (missing(sd)) { sd <- 0.2 }
# eps <- sqrt(.Machine$double.eps)
# B <- diag(1, p, 2)
# X <- matrix(runif(n * p, -2, 2), n, p)
# XB <- X %*% B
# Y <- (sin(XB[, 1]) / (XB[, 2]^2 + eps) + rnorm(n, 0, sd)) > 0
} else {
stop("Got unknown dataset name.")
}
return(list(X = X, Y = as.matrix(Y), B = B, name = name))
}
## Generate reference data (gets re-sampled for each replication)
ds <- dataset(args$dataset, n = 100) # Generates a list with `X`, `Y`, `B` and `name`
# plot(ds$X %*% ds$B, col = 2 * (ds$Y + 1))
################################################################################
metric.subspace <- function(B_true, name = "metric.subspace", normalize = FALSE) {
if (!is.matrix(B_true))
B_true <- as.matrix(B_true)
P_true <- B_true %*% solve(crossprod(B_true), t(B_true))
P_true <- tf$constant(P_true, dtype = 'float32')
if (normalize) {
rankSum <- 2 * ncol(B_true)
c <- 1 / sqrt(min(rankSum, 2 * nrow(B_true) - rankSum))
} else {
c <- sqrt(2)
}
c <- tf$constant(c, dtype = 'float32')
structure(function(model) {
B <- model$get_layer('reduction')$weights
function(y_true, y_pred) {
P <- tf$linalg$matmul(B, B, transpose_b = TRUE)
diff <- P_true - P
c * tf$sqrt(tf$reduce_sum(tf$math$multiply(diff, diff)))
}
},
class = c("nnsdr.metric", "Refinement"),
name = name
)
}
ds <- dataset(args$dataset)
## Build Dimension Reduction Neuronal Network model (matching the data)
nn <- nnsdr$new(
input_shapes = list(x = ncol(ds$X)),
d = ncol(ds$B),
hidden_units = args$hidden_units,
activation = args$activation,
trainable_reduction = args$trainable_reduction,
output_activation = 'sigmoid',
loss = 'binary_crossentropy',
metrics = list('accuracy', metric.subspace(ds$B, normalize = TRUE))
# metrics = list('accuracy')
)
with(ds, {
## Sample test dataset
ds.test <- dataset(ds$name, n = 1000)
nn$reset()
nn$fit(X, Y, epochs = args$epochs,
batch_size = args$batch_size, initializer = args$initializer,
verbose = 2L)
# `OPG` estimate
cat("OPG subspace: ", dist.subspace(B, coef(nn, 'OPG'), normalize = TRUE), '\n')
cat("OPG grassmann:", dist.grassmann(B, coef(nn, 'OPG')), '\n')
# Refinement estimate
cat("Ref subspace: ", dist.subspace(B, coef(nn), normalize = TRUE), '\n')
cat("Ref grassmann:", dist.grassmann(B, coef(nn)), '\n')
# MSE
cat("MSE: ", mean((nn$predict(ds.test$X) - ds.test$Y)^2), '\n')
})
library(ggplot2)
ggplot(nn$history, aes(x = epoch)) +
geom_line(aes(y = loss), col = 'red') +
geom_line(aes(y = accuracy), col = 'blue')
with(dataset('B2', n = 400), {
ggplot(data.frame(XB1 = (X %*% B)[, 1], XB2 = (X %*% B)[, 2], Y = Y)) +
geom_point(aes(x = XB1, y = XB2, col = Y))
})