use csv reader for roach_data

Author: SteveBronder

test/unit/math/laplace/aki_ex_test.cpp

@@ -3,12 +3,9 @@
 #include <stan/math/mix.hpp>
 #include <test/unit/math/rev/fun/util.hpp>
 #include <test/unit/math/laplace/laplace_utility.hpp>
-#include <test/unit/math/laplace/roach_data/mu_bad.hpp>
-#include <test/unit/math/laplace/roach_data/sigma_bad.hpp>
-#include <test/unit/math/laplace/roach_data/y_bad.hpp>
-#include <test/unit/math/laplace/roach_data/mu.hpp>
 #include <test/unit/math/laplace/roach_data/sigmaz.hpp>
 #include <test/unit/math/laplace/roach_data/y.hpp>
+#include <test/unit/math/laplace/csv_reader.hpp>
 
 #include <gtest/gtest.h>
 #include <iostream>
@@ -79,22 +76,20 @@ struct cov_fun_functor {
 TEST(WriteArrayBodySimple, ExceededIteration) {
   stan::test::relative_tolerance rel_tol(5e-2);
   const double integrate_1d_reltol = 1e-8;
-  auto&& mu_bad_raw = stan::test::laplace::roach::mu_bad_raw;
-  Eigen::Map<const Eigen::VectorXd> mu_bad(mu_bad_raw.data(),
-                                           mu_bad_raw.size());
-  auto&& sigma_bad_raw = stan::test::laplace::roach::sigma_bad_raw;
-  Eigen::Map<const Eigen::VectorXd> sigma_bad(sigma_bad_raw.data(),
-                                              sigma_bad_raw.size());
-  auto&& y_bad_raw = stan::test::laplace::roach::y_bad_raw;
-  Eigen::Map<const Eigen::Matrix<int, -1, 1>> y_bad(y_bad_raw.data(),
-                                                    y_bad_raw.size());
-  const int num_samples = mu_bad.cols();
-  const int N = mu_bad.rows();
+  auto mu_samples = stan::math::test::laplace::read_matrix_csv(
+      "./test/unit/math/laplace/roach_data/mu_bad.csv");
+  auto sigmaz_samples = stan::math::test::laplace::read_matrix_csv(
+      "./test/unit/math/laplace/roach_data/sigma_bad.csv");
+  auto y_samples_dbl = stan::math::test::laplace::read_matrix_csv(
+      "./test/unit/math/laplace/roach_data/y_bad.csv");
+  auto y_samples = y_samples_dbl.cast<int>();
+  const int num_samples = mu_samples.cols();
+  const int N = mu_samples.rows();
   std::ostream* pstream = nullptr;
   for (int i = 1; i <= N; ++i) {
-    auto y = y_bad(i - 1);
-    auto mu = mu_bad(i - 1);
-    auto sigmaz = sigma_bad(i - 1);
+    auto y = y_samples(i - 1, 0);
+    auto mu = mu_samples(i - 1, 0);
+    auto sigmaz = sigmaz_samples(i - 1, 0);
     double ll_laplace_val{0};
     try {
       ll_laplace_val = stan::math::laplace_marginal(
@@ -129,15 +124,10 @@ TEST(WriteArrayBodySimple, ExceededIteration) {
 TEST(WriteArrayBodySimple, ExecutesBodyWithHardcodedData) {
   stan::test::relative_tolerance rel_tol(5e-1);
   const double integrate_1d_reltol = 1e-8;
-  auto&& y = stan::test::laplace::roach::y;
-  auto&& sigmaz_samples = stan::test::laplace::roach::sigmaz;
-  auto&& mu_raw = stan::test::laplace::roach::mu_raw;
-  std::size_t mu_cols = mu_raw.size() / y.size();
-  Eigen::MatrixXd mu_samples(y.size(), mu_cols);
-  for (std::size_t i = 0; i < y.size(); ++i) {
-    mu_samples.row(i) = Eigen::Map<const Eigen::RowVectorXd>(
-        mu_raw.data() + i * mu_cols, mu_cols);
-  }
+  auto&& y = stan::math::test::roaches::y;
+  auto&& sigmaz_samples = stan::math::test::roaches::sigmaz;
+  auto mu_samples = stan::math::test::laplace::read_matrix_csv(
+      "./test/unit/math/laplace/roach_data/mu.csv");
   const int num_samples = mu_samples.cols();
   const int N = mu_samples.rows();
   std::ostream* pstream = nullptr;

test/unit/math/laplace/csv_reader.hpp

@@ -0,0 +1,66 @@
+#pragma once
+#include <stan/math/prim/fun/Eigen.hpp>  // or <Eigen/Dense>
+#include <fstream>
+#include <sstream>
+#include <stdexcept>
+#include <string>
+#include <vector>
+
+namespace stan::math::test::laplace {
+
+/**
+ * Reads a CSV of doubles into a dynamically sized Eigen::Matrix.
+ *
+ * @param file_path  Path to a CSV file with R-style numeric matrix
+ *                   (no header, no row names, comma-separated).
+ * @return           Matrix(rows, cols) filled from the file.
+ * @throws std::runtime_error on I/O error or inconsistent column counts.
+ */
+inline Eigen::Matrix<double, Eigen::Dynamic, Eigen::Dynamic> read_matrix_csv(
+    const std::string& file_path) {
+  std::ifstream in(file_path);
+  if (!in.is_open()) {
+    throw std::runtime_error("Could not open CSV file: " + file_path);
+  }
+
+  std::vector<std::vector<double>> buffer;
+  std::string line;
+  while (std::getline(in, line)) {
+    if (line.empty()) {
+      continue;  // skip blank lines
+    }
+    std::vector<double> row;
+    std::stringstream ss(line);
+    std::string cell;
+    while (std::getline(ss, cell, ',')) {
+      try {
+        row.push_back(std::stod(cell));
+      } catch (const std::invalid_argument&) {
+        throw std::runtime_error("Non-numeric value in CSV at line: " + line);
+      }
+    }
+    if (!buffer.empty() && row.size() != buffer[0].size()) {
+      throw std::runtime_error("Inconsistent column count in CSV: expected "
+                               + std::to_string(buffer[0].size()) + " but got "
+                               + std::to_string(row.size()));
+    }
+    buffer.push_back(std::move(row));
+  }
+
+  // If empty file, return a 0×0 matrix
+  if (buffer.empty()) {
+    return Eigen::Matrix<double, Eigen::Dynamic, Eigen::Dynamic>(0, 0);
+  }
+
+  const int rows = static_cast<int>(buffer.size());
+  const int cols = static_cast<int>(buffer[0].size());
+  Eigen::Matrix<double, Eigen::Dynamic, Eigen::Dynamic> mat(rows, cols);
+  for (int i = 0; i < rows; ++i) {
+    for (int j = 0; j < cols; ++j) {
+      mat(i, j) = buffer[i][j];
+    }
+  }
+  return mat;
+}
+
+}  // namespace stan::math::test::laplace