Test softmax

test/layers/test_activation.cu

@@ -0,0 +1,34 @@
+#include "activation.cuh"
+#include <gtest/gtest.h>
+#include <cuda_runtime.h>
+#include <vector>
+
+TEST(ActivationTest, SoftmaxTest) {
+    CUDANet::Layers::Activation activation(
+        CUDANet::Layers::ActivationType::SOFTMAX, 5
+    );
+
+    std::vector<float> input = {0.573f, 0.619f, 0.732f, 0.055f, 0.243f};
+
+    float* d_input;
+    cudaMalloc((void**)&d_input, sizeof(float) * 5);
+    cudaMemcpy(d_input, input.data(), sizeof(float) * 5, cudaMemcpyHostToDevice);
+
+    activation.activate(d_input);
+    std::vector<float> output(5);
+    cudaMemcpy(
+        output.data(), d_input, sizeof(float) * 5, cudaMemcpyDeviceToHost
+    );
+    
+    float sum = 0.0f;
+
+    std::vector<float> expected = {0.22055f, 0.23094f, 0.25856f, 0.13139f, 0.15856f};
+    for (int i = 0; i < 5; ++i) {
+        sum += output[i];
+        EXPECT_NEAR(output[i], expected[i], 1e-5f);
+    }
+
+    EXPECT_NEAR(sum, 1.0f, 1e-5f);
+
+    cudaFree(d_input);
+}