## ----echo = FALSE----------------------------------------- library(GiRaF) library(knitr) options(prompt = " ", continue=' ', width=60) ## ----eval = FALSE----------------------------------------- # # NC.mrf # # Dimension of the lattice # height <- 8 # width <- 10 # # # Interaction parameter # Beta <- 0.6 # Isotropic configuration # # Beta <- c(0.6, 0.6) # Anisotropic configuration for a first # # order dependency structure (nei = 4). # # Beta <- c(0.6, 0.6, 0.6, 0.6) # Anisotropic configuration for a second # # order dependency structure (nei = 8). # # # Number of colors. Automatically set to 2 if not specified. # K <- 2 # # Number of neighbors. Automatically set to 4 if not specified. # G <- 4 # # # Optional potential on sites. Automatically set to NULL if not specified # potential <- runif(K,-1,1) # # Optional borders. Automatically set to NULL if not specified # Top <- Bottom <- sample(0:(K-1), width, replace = TRUE) # Left <- Right <- sample(0:(K-1), height, replace = TRUE) # Corner <- sample(0:(K-1), 4, replace = TRUE) # # # Partition function for the default setting # NC.mrf(h = height, w = width, param = Beta) # # When specifying the number of colors and neighbors # NC.mrf(h = height, w = width, ncolors = K, nei = G, param = Beta) # # When specifying an optional potential on sites # NC.mrf(h = height, w = width, ncolors = K, nei = G, param = Beta, # pot = potential) # # When specifying possible borders. The users will omit to mention all # # the non-existing borders # NC.mrf(h = height, w = width, ncolors = K, nei = G, param = Beta, # top = Top, left = Left, bottom = Bottom, right = Right, # corner = Corner) ## ----eval = FALSE----------------------------------------- # # exact.mrf # # Dimension of the lattice # height <- 8 # width <- 10 # # # Interaction parameter # Beta <- 0.6 # Isotropic configuration # # Beta <- c(0.6, 0.6) # Anisotropic configuration for a first # # order dependency structure (nei = 4). # # Beta <- c(0.6, 0.6, 0.6, 0.6) # Anisotropic configuration for a second # # order dependency structure (nei = 8). # # # Number of colors. Automatically set to 2 if not specified. # K <- 2 # # Number of neighbors. Automatically set to 4 if not specified. # G <- 4 # # # Optional potential on sites. Automatically set to NULL if not specified # potential <- runif(K,-1,1) # # Optional borders. Automatically set to NULL if not specified # Top <- Bottom <- sample(0:(K-1), width, replace = TRUE) # Left <- Right <- sample(0:(K-1), height, replace = TRUE) # Corner <- sample(0:(K-1), 4, replace = TRUE) # # # Exact sampling for the default setting # exact.mrf(h = height, w = width, param = Beta, view = TRUE) # # When specifying the number of colors and neighbors # exact.mrf(h = height, w = width, ncolors = K, nei = G, param = Beta, # view = TRUE) # # When specifying an optional potential on sites # exact.mrf(h = height, w = width, ncolors = K, nei = G, param = Beta, # pot = potential, view = TRUE) # # When specifying possible borders. The users will omit to mention all # # the non-existing borders # exact.mrf(h = height, w = width, ncolors = K, nei = G, param = Beta, # top = Top, left = Left, bottom = Bottom, # right = Right, corner = Corner, view = TRUE) ## ----eval = FALSE----------------------------------------- # # sampler.mrf # # Algorithm settings # n <- 200 # method <- "Gibbs" # # # Dimension of the lattice # height <- width <- 100 # # # Interaction parameter # Beta <- 0.6 # Isotropic configuration # # Beta <- c(0.6, 0.6) # Anisotropic configuration for a first # # order dependency structure (nei = 4). # # Beta <- c(0.6, 0.6, 0.6, 0.6) # Anisotropic configuration for a second # # order dependency structure (nei = 8). # # # Number of colors. Automatically set to 2 if not specified. # K <- 2 # # Number of neighbors. Automatically set to 4 if not specified. # G <- 4 # # # Optional potential on sites. Automatically set to NULL if not specified # potential <- runif(K,-1,1) # # Optional borders. Automatically set to NULL if not specified # Top <- Bottom <- sample(0:(K-1), width, replace = TRUE) # Left <- Right <- sample(0:(K-1), height, replace = TRUE) # Corner <- sample(0:(K-1), 4, replace = TRUE) # # # Sampling method for the default setting # sampler.mrf(iter = n, sampler = method, h = height, w = width, # param = Beta, view = TRUE) # # Sampling using an existing configuration as starting point # sampler.mrf(iter = n, sampler = method, h = height, w = width, # ncolors = K, nei = G, param = Beta, # initialise = FALSE, view = TRUE) # # Specifying optional arguments. The users may omit to mention all # # the non-existing borders # sampler.mrf(iter = n, sampler = method, h = height, w = width, # ncolors = K, nei = G, param = Beta, # pot = potential, top = Top, left = Left, bottom = Bottom, # right = Right, corner = Corner, view = TRUE) # # Gibbs sampler with sequential updates of the sites. # sampler.mrf(iter = n, sampler = "Gibbs", h = height, w = width, # ncolors = K, nei = G, param = Beta, # random = FALSE, view = TRUE)