diff --git a/module3/analyse cours.Rmd b/module3/analyse cours.Rmd
index 7fe69f9a024ce7aa3d4eaa7937aa805010b0f1db..78be6b060374820254bd665448ac34522514217b 100644
--- a/module3/analyse cours.Rmd	
+++ b/module3/analyse cours.Rmd	
@@ -44,15 +44,33 @@ data [lignes_na,]
 library(parsedate)
 ```
 ```{r}
-convert_date = function(date) {
-  ws = paste(date)
+convert_date = function(w) {
+  ws = paste(w)
   iso = paste0(substring(ws,1,4),"-W",substring(ws,5,6))
-  iso
-  parse_iso_8601(iso)
+  as.character(parse_iso_8601(iso))
 }
 ```
 
 ```{r}
-data$date = sapply(data$week, FUN = convert_date)
+data$date = as.Date(convert_date(data$week))
+```
+
+```{r}
+class(data$date)
+```
+```{r}
+data = data[order(data$date),]
+```
+
+
+```{r}
+all(diff(data$date) == 7)
+```
+```{r}
+plot(data$date, data$inc, type="l", xlab="Date", ylab="Incidence hebdomadaire")
+```
+
+```{r}
+with(tail(data, 200), plot(date, inc, type="l", xlab="Date", ylab="Incidence hebdomadaire"))
 ```