diff --git a/quad12/labmoderna/p9/r/regressio.r b/quad12/labmoderna/p9/r/regressio.r
new file mode 100644
index 0000000..d0db5dd
--- /dev/null
+++ b/quad12/labmoderna/p9/r/regressio.r
@@ -0,0 +1,28 @@
+library(svglite)
+library(tikzDevice)
+
+filename = 'regressio'
+
+args = commandArgs(trailingOnly=TRUE)
+
+table <- read.table(paste0('dades/', filename, '.txt'), sep=" ", dec='.', header=TRUE)
+
+fit <- lm(X ~ Y, data = table)
+summary(fit)
+
+# Plot the data
+plotall <- function() {
+  par(mar=c(4,4,0.5,0.5))
+  plot(table$Y, table$X, pch = 4, xlab = "$\\sin(\\theta)$", ylab = "$\\frac{n \\lambda}{2}$ (pm)")
+  abline(fit, col = "#799B6F")
+}
+
+svg(paste0('output/', filename, '.svg'), width = 4*0.82, height = 3*0.82)
+plotall()
+dev.off()
+
+if (length(args) < 1 || args[1] != "preview") {
+  tikz(paste0('output/', filename, '.tex'), width = 4*0.82, height = 3*0.82)
+  plotall()
+  dev.off()
+}