--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/rk_Lorenz.R	Tue Jul 23 03:31:21 2024 +0900
@@ -0,0 +1,29 @@
+dll <- paste("rksub", .Platform$dynlib.ext, sep="")
+dyn.load(dll)
+
+max_i <- as.integer(5000)
+
+r <- .Fortran("rk_sakamoti",
+	as.double(c(0.5, 0.5, 0.5)), 
+	max_i,
+        matrix(0, max_i, 4))
+dyn.unload(dll)
+
+m <- r[[3]]
+colnames(m) <- c("t", "x", "y", "z")
+
+png(filename = "Lorenz system.png", 
+    width = 800, height = 600, bg="white", type="cairo")
+library(scatterplot3d)
+scatterplot3d(m[,2], m[,3], m[,4], 
+    highlight.3d = FALSE, 
+    col.axis = "blue", col.grid = "lightblue", 
+    type = "l", color = "purple", lwd = 2,
+    main = "Lorenz system", 
+    xlab = colnames(m)[2],
+    ylab = colnames(m)[3],
+    zlab = colnames(m)[4],
+    cex.main = 3,
+    cex.lab = 2)
+dev.off()
+