From 019c0a0d2cb2ffde562da4c466d090f5854c7995 Mon Sep 17 00:00:00 2001
From: Stefan Mesken <kappadistributive@gmail.com>
Date: Sat, 13 Jun 2020 23:18:33 +0200
Subject: [PATCH] (de)-serialize a matrix (#589)

* (de)-serialize a matrix

* enable serde-serialize for nalgebra

* fix typo

* add references
---
 Cargo.toml                                    |  2 +-
 src/science/mathematics/linear_algebra.md     |  1 +
 .../linear_algebra/deserialize-matrix.md      | 33 +++++++++++++++++++
 3 files changed, 35 insertions(+), 1 deletion(-)
 create mode 100644 src/science/mathematics/linear_algebra/deserialize-matrix.md

diff --git a/Cargo.toml b/Cargo.toml
index 4a76bc0..9e01325 100755
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -30,7 +30,7 @@ log = "0.4"
 log4rs = "0.8"
 memmap = "0.7"
 mime = "0.3"
-nalgebra = "0.16.12"
+nalgebra = { version = "0.16.12", features = ["serde-serialize"] }
 ndarray = { version = "0.13", features = ["approx"] }
 num = "0.2"
 num_cpus = "1.8"
diff --git a/src/science/mathematics/linear_algebra.md b/src/science/mathematics/linear_algebra.md
index bc339c0..9ce7ae4 100644
--- a/src/science/mathematics/linear_algebra.md
+++ b/src/science/mathematics/linear_algebra.md
@@ -6,5 +6,6 @@
 {{#include linear_algebra/vector-comparison.md}}
 {{#include linear_algebra/vector-norm.md}}
 {{#include linear_algebra/invert-matrix.md}}
+{{#include linear_algebra/deserialize-matrix.md}}
 
 {{#include ../../links.md}}
diff --git a/src/science/mathematics/linear_algebra/deserialize-matrix.md b/src/science/mathematics/linear_algebra/deserialize-matrix.md
new file mode 100644
index 0000000..49ddb7a
--- /dev/null
+++ b/src/science/mathematics/linear_algebra/deserialize-matrix.md
@@ -0,0 +1,33 @@
+## (De)-Serialize a Matrix
+[![ndarray-badge]][ndarray] [![cat-science-badge]][cat-science]
+
+Serialize and deserialize a matrix to and from JSON. Serialization is taken care of
+by [`serde_json::to_string`] and [`serde_json::from_str`] performs deserialization.
+
+Note that serialization followed by deserialization gives back the original matrix.
+
+```rust
+extern crate nalgebra;
+extern crate serde_json;
+
+use nalgebra::DMatrix;
+
+fn main() -> Result<(), std::io::Error> {
+    let row_slice: Vec<i32> = (1..5001).collect();
+    let matrix = DMatrix::from_row_slice(50, 100, &row_slice);
+
+    // serialize matrix
+    let serialized_matrix = serde_json::to_string(&matrix)?;
+
+    // deserialize matrix
+    let deserialized_matrix: DMatrix<i32> = serde_json::from_str(&serialized_matrix)?;
+
+    // verify that `deserialized_matrix` is equal to `matrix`
+    assert!(deserialized_matrix == matrix);
+
+    Ok(())
+}
+```
+
+[`serde_json::to_string`]: https://docs.rs/serde_json/*/serde_json/fn.to_string.html
+[`serde_json::from_str`]: https://docs.rs/serde_json/*/serde_json/fn.from_str.html