1 files changed, 174 insertions, 0 deletions
diff --git a/src/data.rs b/src/data.rs
new file mode 100755
index 0000000..eb1f738
--- /dev/null
+++ b/src/data.rs
@@ -0,0 +1,174 @@
+#![allow(deprecated)]
+
+use std::mem;
+
+use cast::From as _0;
+
+use crate::traits::Data;
+
+macro_rules! impl_data {
+    ($($ty:ty),+) => {
+        $(
+            impl Data for $ty {
+                fn f64(self) -> f64 {
+                    f64::cast(self)
+                }
+            }
+
+            impl<'a> Data for &'a $ty {
+                fn f64(self) -> f64 {
+                    f64::cast(*self)
+                }
+            }
+        )+
+    }
+}
+
+impl_data!(f32, f64, i16, i32, i64, i8, isize, u16, u32, u64, u8, usize);
+
+#[derive(Clone)]
+pub struct Matrix {
+    bytes: Vec<u8>,
+    ncols: usize,
+    nrows: usize,
+}
+
+impl Matrix {
+    pub fn new<I>(rows: I, scale: <I::Item as Row>::Scale) -> Matrix
+    where
+        I: Iterator,
+        I::Item: Row,
+    {
+        let ncols = I::Item::ncols();
+        let bytes_per_row = ncols * mem::size_of::<f64>();
+        let mut bytes = Vec::with_capacity(rows.size_hint().0 * bytes_per_row);
+
+        let mut nrows = 0;
+        for row in rows {
+            nrows += 1;
+            row.append_to(&mut bytes, scale);
+        }
+
+        Matrix {
+            bytes,
+            ncols,
+            nrows,
+        }
+    }
+
+    pub fn bytes(&self) -> &[u8] {
+        &self.bytes
+    }
+
+    pub fn ncols(&self) -> usize {
+        self.ncols
+    }
+
+    pub fn nrows(&self) -> usize {
+        self.nrows
+    }
+}
+
+/// Data that can serve as a row of the data matrix
+pub trait Row {
+    /// Private
+    type Scale: Copy;
+
+    /// Append this row to a buffer
+    fn append_to(self, buffer: &mut Vec<u8>, scale: Self::Scale);
+    /// Number of columns of the row
+    fn ncols() -> usize;
+}
+
+fn write_f64(w: &mut impl std::io::Write, f: f64) -> std::io::Result<()> {
+    w.write_all(&f.to_bits().to_le_bytes())
+}
+
+impl<A, B> Row for (A, B)
+where
+    A: Data,
+    B: Data,
+{
+    type Scale = (f64, f64);
+
+    fn append_to(self, buffer: &mut Vec<u8>, scale: (f64, f64)) {
+        let (a, b) = self;
+
+        write_f64(buffer, a.f64() * scale.0).unwrap();
+        write_f64(buffer, b.f64() * scale.1).unwrap();
+    }
+
+    fn ncols() -> usize {
+        2
+    }
+}
+
+impl<A, B, C> Row for (A, B, C)
+where
+    A: Data,
+    B: Data,
+    C: Data,
+{
+    type Scale = (f64, f64, f64);
+
+    fn append_to(self, buffer: &mut Vec<u8>, scale: (f64, f64, f64)) {
+        let (a, b, c) = self;
+
+        write_f64(buffer, a.f64() * scale.0).unwrap();
+        write_f64(buffer, b.f64() * scale.1).unwrap();
+        write_f64(buffer, c.f64() * scale.2).unwrap();
+    }
+
+    fn ncols() -> usize {
+        3
+    }
+}
+
+impl<A, B, C, D> Row for (A, B, C, D)
+where
+    A: Data,
+    B: Data,
+    C: Data,
+    D: Data,
+{
+    type Scale = (f64, f64, f64, f64);
+
+    fn append_to(self, buffer: &mut Vec<u8>, scale: (f64, f64, f64, f64)) {
+        let (a, b, c, d) = self;
+
+        write_f64(buffer, a.f64() * scale.0).unwrap();
+        write_f64(buffer, b.f64() * scale.1).unwrap();
+        write_f64(buffer, c.f64() * scale.2).unwrap();
+        write_f64(buffer, d.f64() * scale.3).unwrap();
+    }
+
+    fn ncols() -> usize {
+        4
+    }
+}
+
+impl<A, B, C, D, E> Row for (A, B, C, D, E)
+where
+    A: Data,
+    B: Data,
+    C: Data,
+    D: Data,
+    E: Data,
+{
+    type Scale = (f64, f64, f64, f64, f64);
+
+    #[cfg_attr(feature = "cargo-clippy", allow(clippy::many_single_char_names))]
+    fn append_to(self, buffer: &mut Vec<u8>, scale: (f64, f64, f64, f64, f64)) {
+        let (a, b, c, d, e) = self;
+
+        write_f64(buffer, a.f64() * scale.0).unwrap();
+        write_f64(buffer, b.f64() * scale.1).unwrap();
+        write_f64(buffer, c.f64() * scale.2).unwrap();
+        write_f64(buffer, d.f64() * scale.3).unwrap();
+        write_f64(buffer, e.f64() * scale.4).unwrap();
+    }
+
+    fn ncols() -> usize {
+        5
+    }
+}