docs: add dot prod & scalar_select

tfhe/docs/SUMMARY.md

@@ -30,8 +30,9 @@
   * [Min/Max operations](fhe-computation/operations/min-max-operations.md)
   * [Ternary conditional operations](fhe-computation/operations/ternary-conditional-operations.md)
   * [Casting operations](fhe-computation/operations/casting-operations.md)
-  * [Boolean Operations](fhe-computation/operations/boolean-operations.md)
-  * [String Operations](fhe-computation/operations/string-operations.md)
+  * [Boolean operations](fhe-computation/operations/boolean-operations.md)
+  * [String operations](fhe-computation/operations/string-operations.md)
+  * [Dot product](fhe-computation/operations/dot-product.md)
 * [Core workflow](fhe-computation/compute/README.md)
   * [Configuration and key generation](fhe-computation/compute/configure-and-generate-keys.md)
   * [Server key](fhe-computation/compute/set-the-server-key.md)

tfhe/docs/fhe-computation/operations/dot-product.md

@@ -0,0 +1,37 @@
+# Dot Product
+
+This document details the dot product operations supported by **TFHE-rs**.
+
+
+| name          | symbol         | type   |
+|---------------|----------------| ------ |
+| Dot Product   | `dot_product`  | Binary |
+
+
+Currently, the dot product supports the following case:
+- One operand is a slice of `FheBool`
+- The other operand is a slice of clear values (e.g., `u64`)
+- Both slices must be of the same length
+
+The following example shows how to perform dot product:
+
+```rust
+use tfhe::prelude::*;
+use tfhe::{generate_keys, set_server_key, ConfigBuilder, FheBool, FheUint8};
+
+fn main() {
+    let (client_key, server_key) = generate_keys(ConfigBuilder::default());
+    set_server_key(server_key);
+  
+    let a = [true, false, true]
+     .into_iter()
+     .map(|b| FheBool::encrypt(b, &client_key))
+     .collect::<Vec<_>>();
+   
+    let b = [2u8, 3u8, 4u8];
+   
+    let result = FheUint8::dot_product(&a, &b);
+    let decrypted: u8 = result.decrypt(&client_key);
+    assert_eq!(decrypted, 6u8);
+}
+```

tfhe/docs/fhe-computation/operations/ternary-conditional-operations.md

@@ -49,6 +49,21 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
     let clear_res: i32 = encrypted_res.decrypt(&client_key);
     assert_eq!(clear_res, clear_a);
     
+    // Ternary conditional also supports operands that are in clear (except for the condition)
+    // with the `scalar` prefix
+    let encrypted_res = &encrypted_comp.scalar_select(&encrypted_a, clear_b);
+    let clear_res: i32 = encrypted_res.decrypt(&client_key);
+    assert_eq!(clear_res, clear_a);
+
+    let encrypted_res = &encrypted_comp.scalar_select(clear_a, &encrypted_b);
+    let clear_res: i32 = encrypted_res.decrypt(&client_key);
+    assert_eq!(clear_res, clear_a);
+
+    // When both possible results are in clear the form to be used is
+    let encrypted_res = FheInt32::select(encrypted_comp, clear_a, clear_b);
+    let clear_res: i32 = encrypted_res.decrypt(&client_key);
+    assert_eq!(clear_res, clear_a);
+   
     Ok(())
 }
 ```

tfhe/src/test_user_docs.rs

@@ -109,6 +109,10 @@ mod test_cpu_doc {
         "../docs/fhe-computation/operations/string-operations.md",
         operations_string_operations
     );
+    doctest!(
+        "../docs/fhe-computation/operations/dot-product.md",
+        operations_dot_product
+    );
 
     // TOOLING
     doctest!("../docs/fhe-computation/tooling/debug.md", tooling_debug);