Fix up the test to compare with R.

.gitignore

@@ -29,3 +29,4 @@ backup
 coverage
 coverage/*
 .venv
+samples.txt

cpp/Makefile

@@ -22,7 +22,7 @@ debug_build:
 test: build
 	./builddir/fuc2it -v
 
-r_test:
+r_test: test
 	$(R_SCRIPT) tests/confirm.r
 
 run: build test

cpp/include/stats.hpp

@@ -67,9 +67,6 @@ struct Stats {
 
     auto as_ms = std::chrono::duration_cast<std::chrono::nanoseconds>(elapsed);
 
-    fmt::println("sample time: {} vs. my calc: {}; as_ms: {}",
-        elapsed.count(), 1.0/elapsed.count(), as_ms.count());
-
     if(elapsed.count() > 0.0) {
       sample(1.0/elapsed.count());
     }

cpp/tests/confirm.r

@@ -1,7 +1,3 @@
-samples <- read.table("bad_samples.txt")
-t.test(samples$V1, samples$V2)
-
-
 samples <- read.table("samples.txt")
 print(samples)
 t.test(samples$V1, samples$V2)

cpp/tests/stats_tests.cpp

@@ -113,11 +113,20 @@ namespace stats_tests {
       welf2.sample(num + skew_factor);
     }
 
-    fmt::println("welford samples t-test:");
     welf.t_test(welf2);
-
-    fmt::println("naive algebra samples t-test:");
     stats.t_test(stats2);
+
+    auto stats_test = stats.t_test(stats2);
+    auto welf_test = welf.t_test(welf2);
+
+    ALMOST_EQUAL(stats_test.t_stat, welf_test.t_stat, 5);
+    ALMOST_EQUAL(stats_test.dof, welf_test.dof, 1);
+    ALMOST_EQUAL(stats_test.p_val, welf_test.p_val, 5);
+
+    fmt::println("welford samples t-test: t-val: {}, dof: {}, p-val: {}",
+        welf_test.t_stat, welf_test.dof, welf_test.p_val);
+    fmt::println("naive algebra samples t-test: t-val: {}, dof: {}, p-val: {}",
+        stats_test.t_stat, stats_test.dof, stats_test.p_val);
   }
 
   void failing_bad_t_test() {