1 files changed, 6 insertions, 2 deletions
diff --git a/examples/errorbar.rs b/examples/errorbar.rs
index 7f11dd9..75c5dbe 100644
--- a/examples/errorbar.rs
+++ b/examples/errorbar.rs
@@ -8,12 +8,12 @@ use itertools::Itertools;
 
 use num_traits::sign::Signed;
 
+const OUT_FILE_NAME: &'static str = "plotters-doc-data/errorbar.png";
 fn main() -> Result<(), Box<dyn std::error::Error>> {
     let data = generate_random_data();
     let down_sampled = down_sample(&data[..]);
 
-    let root =
-        BitMapBackend::new("plotters-doc-data/errorbar.png", (1024, 768)).into_drawing_area();
+    let root = BitMapBackend::new(OUT_FILE_NAME, (1024, 768)).into_drawing_area();
 
     root.fill(&WHITE)?;
 
@@ -50,6 +50,10 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
         .background_style(WHITE.filled())
         .draw()?;
 
+    // To avoid the IO failure being ignored silently, we manually call the present function
+    root.present().expect("Unable to write result to file, please make sure 'plotters-doc-data' dir exists under current dir");
+    println!("Result has been saved to {}", OUT_FILE_NAME);
+
     Ok(())
 }