Green kernel (#105)

* WIP: Laplace kernels

* WIP: Clean-Up and unit tests

* Unit tests for Laplace 3d working.

* Updated documentation.

* Updated cargo path for rlst

* Updated Rayon version

* Fixed num_cpus version

---------

Co-authored-by: Matthew Scroggs <[email protected]>

.cargo/config.toml

@@ -0,0 +1,3 @@
+[build]
+rustflags = ["-C", "target-cpu=native"]
+

Cargo.toml

@@ -9,6 +9,7 @@ members = [
     "quadrature",
     "tools",
     "tree",
+    "kernel",
     "traits",
 ]
 
@@ -21,5 +22,6 @@ default-members = [
     "quadrature",
     "tools",
     "tree",
+    "kernel",
     "traits",
 ]

fmm/Cargo.toml

@@ -35,8 +35,8 @@ blas-src = { version = "*", features = ["openblas"] }
 openblas-src = { version = "*", features = ["cblas", "system"] }
 ndarray-linalg = { version = "*", features = ["openblas-system"] }
 float-cmp = "0.9.0"
-rayon = "1.5.1"
-num_cpus = "1.0"
+rayon = "1.7"
+num_cpus = "1"
 ndrustfft = "0.4.0"
 num = "0.4"
 ndarray-ndimage = "0.3.0"

kernel/Cargo.toml

@@ -0,0 +1,33 @@
+[features]
+# Treat warnings as a build error.
+strict = []
+
+[package]
+name = "bempp-kernel"
+version = "0.1.0"
+edition = "2021"
+authors = ["Timo Betcke <[email protected]>"]
+description = "Evaluation of Green's function kernels."
+license = "BSD-3-Clause"
+homepage = "https://github.com/bempp/bempp-rs"
+repository = "https://github.com/bempp/bempp-rs"
+readme = "README.md"
+keywords = ["numerics"]
+categories = ["mathematics", "science"]
+
+[lib]
+name = "bempp_kernel"
+crate-type = ["lib", "cdylib"]
+
+[dependencies]
+bempp-tools = { path = "../tools"}
+bempp-traits = { path = "../traits" }
+paste = "1.*"
+libc = "0.2"
+approx = "0.5"
+rayon = "1.7"
+num = "0.4"
+num_cpus = "1"
+
+[dev-dependencies]
+rlst = {git = "https://github.com/linalg-rs/rlst.git" }

kernel/src/helpers.rs

@@ -0,0 +1,45 @@
+use crate::traits::Kernel;
+use crate::types::EvalType;
+use bempp_traits::types::Scalar;
+
+pub(crate) fn check_dimensions_evaluate<K: Kernel, T: Scalar>(
+    kernel: &K,
+    eval_type: EvalType,
+    sources: &[T::Real],
+    targets: &[T::Real],
+    charges: &[T],
+    result: &[T],
+) {
+    assert!(
+        sources.len() % kernel.space_dimension() == 0,
+        "Length of sources {} is not a multiple of space dimension {}.",
+        sources.len(),
+        kernel.space_dimension()
+    );
+
+    assert!(
+        targets.len() % kernel.space_dimension() == 0,
+        "Length of targets {} is not a multiple of space dimension {}.",
+        sources.len(),
+        kernel.space_dimension()
+    );
+
+    let nsources = sources.len() / kernel.space_dimension();
+    let ntargets = targets.len() / kernel.space_dimension();
+
+    assert_eq!(
+        charges.len(),
+        nsources,
+        "Wrong dimension for `charges`. {} != {} ",
+        charges.len(),
+        nsources,
+    );
+
+    assert_eq!(
+        result.len(),
+        kernel.range_component_count(eval_type) * ntargets,
+        "Wrong dimension for `result`. {} != {} ",
+        result.len(),
+        ntargets * kernel.range_component_count(eval_type),
+    );
+}