1 files changed, 34 insertions, 0 deletions
diff --git a/meap/meap-code/ch5/ch5-fixed-width.rs b/meap/meap-code/ch5/ch5-fixed-width.rs
new file mode 100755
index 0000000..fa0b867
--- /dev/null
+++ b/meap/meap-code/ch5/ch5-fixed-width.rs
@@ -0,0 +1,34 @@
+use num::{Float};
+
+/// Q1_7 - single byte representation of a fixed point number with range [-1, 1]. 
+/// The name refers to the Texas Instrument representation
+/// 
+/// References:
+///  - English Wikipedia: "Q (number format)" https://en.wikipedia.org/wiki/Q_(number_format)
+struct Q1_7(i8); // tuple struct holding a i8 value
+
+impl From<T: Float> for Q1_7 {
+    fn from (n:T) -> Self {
+        let val = if n > 1.0 { // out of bounds numbers are coerced to the maximum of the range
+            1
+        } else if n < -1.0 {
+            -1
+        } else {
+            n * (2**7)
+        }
+
+        Q1_7(val as i8)
+    }
+}
+
+impl From for U: Float {
+    fn from(q: Q1_7) -> U {
+        q.0 * (2 ** -7)
+    }
+}
+
+mod tests {
+    use super::*;
+
+    test
+}
+\ No newline at end of file