3rd phase.

9 files changed, 134 insertions, 5 deletions

diff --git a/candle-book/src/SUMMARY.md b/candle-book/src/SUMMARY.md
index ddd6e916..e35a865f 100644
--- a/candle-book/src/SUMMARY.md
+++ b/candle-book/src/SUMMARY.md
@@ -12,11 +12,11 @@
 
 - [Running a model](inference/README.md)
     - [Using the hub](inference/hub.md)
-    - [Serialization](inference/serialization.md)
-    - [Advanced Cuda usage](inference/cuda/README.md)
-        - [Writing a custom kernel](inference/cuda/writing.md)
-        - [Porting a custom kernel](inference/cuda/porting.md)
 - [Error management](error_manage.md)
+- [Advanced Cuda usage](cuda/README.md)
+    - [Writing a custom kernel](cuda/writing.md)
+    - [Porting a custom kernel](cuda/porting.md)
+- [Using MKL](advanced/mkl.md)
 - [Creating apps](apps/README.md)
     - [Creating a WASM app](apps/wasm.md)
     - [Creating a REST api webserver](apps/rest.md)
@@ -24,4 +24,4 @@
 - [Training](training/README.md)
     - [MNIST](training/mnist.md)
     - [Fine-tuning](training/finetuning.md)
-- [Using MKL](advanced/mkl.md)
+    - [Serialization](training/serialization.md)
diff --git a/candle-book/src/cuda/README.md b/candle-book/src/cuda/README.md
new file mode 100644
index 00000000..68434cbf
--- /dev/null
+++ b/candle-book/src/cuda/README.md
@@ -0,0 +1 @@
+# Advanced Cuda usage
diff --git a/candle-book/src/cuda/porting.md b/candle-book/src/cuda/porting.md
new file mode 100644
index 00000000..e332146d
--- /dev/null
+++ b/candle-book/src/cuda/porting.md
@@ -0,0 +1 @@
+# Porting a custom kernel
diff --git a/candle-book/src/cuda/writing.md b/candle-book/src/cuda/writing.md
new file mode 100644
index 00000000..0fe1f3dc
--- /dev/null
+++ b/candle-book/src/cuda/writing.md
@@ -0,0 +1 @@
+# Writing a custom kernel
diff --git a/candle-book/src/error_manage.md b/candle-book/src/error_manage.md
index 042e191f..af7593d6 100644
--- a/candle-book/src/error_manage.md
+++ b/candle-book/src/error_manage.md
@@ -1 +1,39 @@
 # Error management
+
+You might have seen in the code base a lot of `.unwrap()` or `?`.
+If you're unfamiliar with Rust check out the [Rust book](https://doc.rust-lang.org/book/ch09-02-recoverable-errors-with-result.html)
+for more information.
+
+What's important to know though, is that if you want to know *where* a particular operation failed
+You can simply use `RUST_BACKTRACE=1` to get the location of where the model actually failed.
+
+Let's see on failing code:
+
+```rust,ignore
+let x = Tensor::zeros((1, 784), DType::F32, &device)?;
+let y = Tensor::zeros((1, 784), DType::F32, &device)?;
+let z = x.matmul(&y)?;
+```
+
+Will print at runtime:
+
+```bash
+Error: ShapeMismatchBinaryOp { lhs: [1, 784], rhs: [1, 784], op: "matmul" }
+``` 
+
+
+After adding `RUST_BACKTRACE=1`:
+
+
+```bash
+Error: WithBacktrace { inner: ShapeMismatchBinaryOp { lhs: [1, 784], rhs: [1, 784], op: "matmul" }, backtrace: Backtrace [{ fn: "candle::error::Error::bt", file: "/home/nicolas/.cargo/git/checkouts/candle-5bb8ef7e0626d693/f291065/candle-core/src/error.rs", line: 200 }, { fn: "candle::tensor::Tensor::matmul", file: "/home/nicolas/.cargo/git/checkouts/candle-5bb8ef7e0626d693/f291065/candle-core/src/tensor.rs", line: 816 }, { fn: "myapp::main", file: "./src/main.rs", line: 29 }, { fn: "core::ops::function::FnOnce::call_once", file: "/rustc/8ede3aae28fe6e4d52b38157d7bfe0d3bceef225/library/core/src/ops/function.rs", line: 250 }, { fn: "std::sys_common::backtrace::__rust_begin_short_backtrace", file: "/rustc/8ede3aae28fe6e4d52b38157d7bfe0d3bceef225/library/std/src/sys_common/backtrace.rs", line: 135 }, { fn: "std::rt::lang_start::{{closure}}", file: "/rustc/8ede3aae28fe6e4d52b38157d7bfe0d3bceef225/library/std/src/rt.rs", line: 166 }, { fn: "core::ops::function::impls::<impl core::ops::function::FnOnce<A> for &F>::call_once", file: "/rustc/8ede3aae28fe6e4d52b38157d7bfe0d3bceef225/library/core/src/ops/function.rs", line: 284 }, { fn: "std::panicking::try::do_call", file: "/rustc/8ede3aae28fe6e4d52b38157d7bfe0d3bceef225/library/std/src/panicking.rs", line: 500 }, { fn: "std::panicking::try", file: "/rustc/8ede3aae28fe6e4d52b38157d7bfe0d3bceef225/library/std/src/panicking.rs", line: 464 }, { fn: "std::panic::catch_unwind", file: "/rustc/8ede3aae28fe6e4d52b38157d7bfe0d3bceef225/library/std/src/panic.rs", line: 142 }, { fn: "std::rt::lang_start_internal::{{closure}}", file: "/rustc/8ede3aae28fe6e4d52b38157d7bfe0d3bceef225/library/std/src/rt.rs", line: 148 }, { fn: "std::panicking::try::do_call", file: "/rustc/8ede3aae28fe6e4d52b38157d7bfe0d3bceef225/library/std/src/panicking.rs", line: 500 }, { fn: "std::panicking::try", file: "/rustc/8ede3aae28fe6e4d52b38157d7bfe0d3bceef225/library/std/src/panicking.rs", line: 464 }, { fn: "std::panic::catch_unwind", file: "/rustc/8ede3aae28fe6e4d52b38157d7bfe0d3bceef225/library/std/src/panic.rs", line: 142 }, { fn: "std::rt::lang_start_internal", file: "/rustc/8ede3aae28fe6e4d52b38157d7bfe0d3bceef225/library/std/src/rt.rs", line: 148 }, { fn: "std::rt::lang_start", file: "/rustc/8ede3aae28fe6e4d52b38157d7bfe0d3bceef225/library/std/src/rt.rs", line: 165 }, { fn: "main" }, { fn: "__libc_start_main" }, { fn: "_start" }] }
+```
+
+Not super pretty at the moment, but we can see error occured on `{ fn: "myapp::main", file: "./src/main.rs", line: 29 }`
+
+
+Another thing to note, is that since Rust is compiled it is not necessarily as easy to recover proper stacktraces
+especially in release builds. We're using [`anyhow`](https://docs.rs/anyhow/latest/anyhow/) for that.
+The library is still young, please [report](https://github.com/LaurentMazare/candle/issues) any issues detecting where an error is coming from.
+
+
diff --git a/candle-book/src/inference/README.md b/candle-book/src/inference/README.md
index c82f85e1..1b75a310 100644
--- a/candle-book/src/inference/README.md
+++ b/candle-book/src/inference/README.md
@@ -1 +1,7 @@
 # Running a model
+
+
+In order to run an existing model, you will need to download and use existing weights.
+Most models are already available on https://huggingface.co/ in [`safetensors`](https://github.com/huggingface/safetensors) format.
+
+Let's get started by running an old model : `bert-base-uncased`.
diff --git a/candle-book/src/inference/hub.md b/candle-book/src/inference/hub.md
index 6242c070..8cf375d7 100644
--- a/candle-book/src/inference/hub.md
+++ b/candle-book/src/inference/hub.md
@@ -1 +1,80 @@
 # Using the hub
+
+Install the [`hf-hub`](https://github.com/huggingface/hf-hub) crate:
+
+```bash
+cargo add hf-hub
+```
+
+Then let's start by downloading the [model file](https://huggingface.co/bert-base-uncased/tree/main).
+
+
+```rust
+# extern crate candle;
+# extern crate hf_hub;
+use hf_hub::api::sync::Api;
+use candle::Device;
+
+let api = Api::new().unwrap();
+let repo = api.model("bert-base-uncased".to_string());
+
+let weights = repo.get("model.safetensors").unwrap();
+
+let weights = candle::safetensors::load(weights, &Device::Cpu);
+```
+
+We now have access to all the [tensors](https://huggingface.co/bert-base-uncased?show_tensors=true) within the file.
+
+
+## Using async 
+
+`hf-hub` comes with an async API.
+
+```bash
+cargo add hf-hub --features tokio
+```
+
+```rust,ignore
+# extern crate candle;
+# extern crate hf_hub;
+use hf_hub::api::tokio::Api;
+use candle::Device;
+
+let api = Api::new().unwrap();
+let repo = api.model("bert-base-uncased".to_string());
+
+let weights = repo.get("model.safetensors").await.unwrap();
+
+let weights = candle::safetensors::load(weights, &Device::Cpu);
+```
+
+
+## Using in a real model.
+
+Now that we have our weights, we can use them in our bert architecture:
+
+```rust
+# extern crate candle;
+# extern crate candle_nn;
+# extern crate hf_hub;
+# use hf_hub::api::sync::Api;
+# use candle::Device;
+# 
+# let api = Api::new().unwrap();
+# let repo = api.model("bert-base-uncased".to_string());
+# 
+# let weights = repo.get("model.safetensors").unwrap();
+use candle_nn::Linear;
+
+let weights = candle::safetensors::load(weights, &Device::Cpu);
+
+let weight = weights.get("bert.encoder.layer.0.attention.self.query.weight").unwrap();
+let bias = weights.get("bert.encoder.layer.0.attention.self.query.bias").unwrap();
+
+let linear = Linear::new(weight, Some(bias));
+
+let input_ids = Tensor::zeros((3, 7680), DType::F32, &Device::Cpu).unwrap();
+let output = linear.forward(&input_ids);
+```
+
+For a full reference, you can check out the full [bert](https://github.com/LaurentMazare/candle/tree/main/candle-examples/examples/bert) example.
diff --git a/candle-book/src/inference/serialization.md b/candle-book/src/inference/serialization.md
index 0dfc62d3..133ff025 100644
--- a/candle-book/src/inference/serialization.md
+++ b/candle-book/src/inference/serialization.md
@@ -1 +1,3 @@
 # Serialization
+
+Once you have a r
diff --git a/candle-book/src/training/serialization.md b/candle-book/src/training/serialization.md
new file mode 100644
index 00000000..0dfc62d3
--- /dev/null
+++ b/candle-book/src/training/serialization.md
@@ -0,0 +1 @@
+# Serialization