Add penta example

examples/autumn_leaves.rs

@@ -0,0 +1,21 @@
+use musika_rs::{Bar, A, B, C, D, E, F, G};
+
+fn main() {
+    let chord = E.dom7();
+    println!("E7: {chord:X}");
+
+    let bar0 = Bar::new().with_silence(1);
+    let bar1 = Bar::new().with_chord(D.min7(), 1);
+    let bar2 = Bar::new().with_chord(G.dom7(), 1);
+    let bar3 = Bar::new().with_chord(C.maj7(), 1);
+    let bar4 = Bar::new().with_chord(F.maj7(), 1);
+    let bar5 = Bar::new().with_chord(B.min7b5(), 1);
+    let bar6 = Bar::new().with_chord(E.dom7(), 1);
+    let bar7 = Bar::new().with_chord(A.min7(), 1);
+    let s = [bar0, bar1, bar2, bar3, bar4, bar5, bar6, bar7]
+        .into_iter()
+        .map(|bar| format!("{bar}"))
+        .collect::<Vec<_>>()
+        .join(" | ");
+    println!("LH: | {s} |");
+}

src/scales/penta_minor.rs

@@ -0,0 +1,35 @@
+use super::Scales;
+use crate::Note;
+
+pub fn minor(tonic: Note) -> Scales {
+    let steps = [3, 2, 2, 3];
+    Scales::minor_with_steps(" penta_minor", tonic, steps.into_iter())
+}
+
+pub fn pentatonic_minor(tonic: Note) -> Scales {
+    let steps = [3, 2, 2, 3, 2];
+    Scales::minor_with_steps(" penta minor", tonic, steps.into_iter())
+}
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::{A, C};
+
+    #[test]
+    fn test_minor() {
+        let scale = minor(C);
+        assert_eq!(format!("{scale:X}"), "C minor [C, D, D#, F, G, G#, A#, C]");
+        assert_eq!(format!("{scale:x}"), "C minor [C, D, Eb, F, G, Ab, Bb, C]");
+    }
+
+    #[test]
+    fn test_penta_minor() {
+        let scale = pentatonic_minor(A);
+        assert_eq!(format!("{scale:X}"), "A penta minor [A, C, D, E, G, A]");
+        assert_eq!(format!("{scale:x}"), "A penta minor [A, C, D, E, G, A]");
+
+        let scale = pentatonic_minor(D);
+        assert_eq!(format!("{scale:X}"), "D penta minor [D, E, F, G, B, D]");
+        assert_eq!(format!("{scale:x}"), "D penta minor [D, E, F, G, B, D]");
+    }
+}