Add get_emission

cxx/emissions/BUILD

@@ -9,6 +9,19 @@ cc_library(
     ],
 )
 
+cc_library(
+    name = "get_emission",
+    srcs = ["get_emission.cc"],
+    hdrs = ["get_emission.hh"],
+    visibility = ["//:__subpackages__"],
+    deps = [
+        ":bitflip",
+        ":gaussian",
+        ":simple_string",
+        ":sometimes",
+    ],
+)
+
 cc_library(
     name = "bitflip",
     srcs = ["bitflip.hh"],
@@ -46,6 +59,16 @@ cc_library(
     ],
 )
 
+cc_test(
+    name = "get_emission_test",
+    srcs = ["get_emission_test.cc"],
+    deps = [
+        ":get_emission",
+        "@boost//:algorithm",
+        "@boost//:test",
+    ],
+)
+
 cc_test(
     name = "bitflip_test",
     srcs = ["bitflip_test.cc"],

cxx/emissions/get_emission.cc

@@ -0,0 +1,24 @@
+// Copyright 2024
+// See LICENSE.txt
+
+#include "emissions/get_emission.hh"
+
+#include <cassert>
+
+#include "emissions/bitflip.hh"
+#include "emissions/gaussian.hh"
+#include "emissions/simple_string.hh"
+
+EmissionVariant get_emission(const std::string& emission_name) {
+  if (emission_name == "gaussian") {
+    return new GaussianEmission();
+  } else if (emission_name == "simple_string") {
+    return new SimpleStringEmission();
+  } else if (emission_name == "sometimes_gaussian") {
+    return new SometimesGaussian();
+  } else if (emission_name == "sometimes_bitflip") {
+    return new SometimesBitFlip();
+  }
+  printf("Unknown emission name %s\n", emission_name.c_str());
+  assert(false);
+}

cxx/emissions/get_emission.hh

@@ -0,0 +1,20 @@
+// Copyright 2024
+// See LICENSE.txt
+
+#pragma once
+
+#include <string>
+#include <variant>
+
+#include "emissions/sometimes.hh"
+
+class BitFlip;
+class GaussianEmission;
+class SimpleStringEmission;
+using SometimesBitFlip = Sometimes<BitFlip, bool>;
+using SometimesGaussian = Sometimes<GaussianEmission, double>;
+
+using EmissionVariant = std::variant<GaussianEmission*, SometimesGaussian*,
+                                     SometimesBitFlip*, SimpleStringEmission*>;
+
+EmissionVariant get_emission(const std::string& emission_name);

cxx/emissions/get_emission_test.cc

@@ -0,0 +1,41 @@
+#define BOOST_TEST_MODULE test get_emission
+
+#include "emissions/get_emission.hh"
+
+#include <boost/test/included/unit_test.hpp>
+
+#include "emissions/bitflip.hh"
+#include "emissions/gaussian.hh"
+#include "emissions/simple_string.hh"
+
+BOOST_AUTO_TEST_CASE(test_get_emission_gaussian) {
+  EmissionVariant ev = get_emission("gaussian");
+  GaussianEmission* ge = std::get<GaussianEmission*>(ev);
+
+  ge->incorporate(std::make_pair<double, double>(2.0, 2.1));
+  BOOST_TEST(ge->N == 1);
+}
+
+BOOST_AUTO_TEST_CASE(test_get_emission_simple_string) {
+  EmissionVariant ev = get_emission("simple_string");
+  SimpleStringEmission* sse = std::get<SimpleStringEmission*>(ev);
+
+  sse->incorporate(std::make_pair<std::string, std::string>("hello", "hi"));
+  BOOST_TEST(sse->N == 1);
+}
+
+BOOST_AUTO_TEST_CASE(test_get_emission_sometimes_gaussian) {
+  EmissionVariant ev = get_emission("sometimes_gaussian");
+  SometimesGaussian* sg = std::get<SometimesGaussian*>(ev);
+
+  sg->incorporate(std::make_pair<double, double>(2.0, 2.1));
+  BOOST_TEST(sg->N == 1);
+}
+
+BOOST_AUTO_TEST_CASE(test_get_emission_sometimes_bitflip) {
+  EmissionVariant ev = get_emission("sometimes_bitflip");
+  SometimesBitFlip* sbf = std::get<SometimesBitFlip*>(ev);
+
+  sbf->incorporate(std::make_pair<bool, bool>(true, true));
+  BOOST_TEST(sbf->N == 1);
+}