1 files changed, 44 insertions, 0 deletions
diff --git a/generic/SoftPlus.c b/generic/SoftPlus.c
new file mode 100644
index 0000000..7a097fb
--- /dev/null
+++ b/generic/SoftPlus.c
@@ -0,0 +1,44 @@
+#ifndef TH_GENERIC_FILE
+#define TH_GENERIC_FILE "generic/SoftPlus.c"
+#else
+
+static int nn_(SoftPlus_updateOutput)(lua_State *L)
+{
+  THTensor *input = luaT_checkudata(L, 2, torch_(Tensor_id));
+  THTensor *output = luaT_getfieldcheckudata(L, 1, "output", torch_(Tensor_id));
+  
+  THTensor_(resizeAs)(output, input);
+
+  TH_TENSOR_APPLY2(real, output, real, input,               \
+                   *output_data = log1p(exp(*input_data));)
+    
+    return 1;
+}
+
+static int nn_(SoftPlus_updateGradInput)(lua_State *L)
+{
+  THTensor *gradOutput = luaT_checkudata(L, 3, torch_(Tensor_id));
+  THTensor *output = luaT_getfieldcheckudata(L, 1, "output", torch_(Tensor_id));
+  THTensor *gradInput = luaT_getfieldcheckudata(L, 1, "gradInput", torch_(Tensor_id));
+
+  THTensor_(resizeAs)(gradInput, output);
+  TH_TENSOR_APPLY3(real, gradInput, real, gradOutput, real, output,    \
+                   real z = exp(*output_data);                         \
+                   *gradInput_data = *gradOutput_data * (z - 1.)/z;)
+    return 1;
+}
+
+static const struct luaL_Reg nn_(SoftPlus__) [] = {
+  {"SoftPlus_updateOutput", nn_(SoftPlus_updateOutput)},
+  {"SoftPlus_updateGradInput", nn_(SoftPlus_updateGradInput)},
+  {NULL, NULL}
+};
+
+static void nn_(SoftPlus_init)(lua_State *L)
+{
+  luaT_pushmetaclass(L, torch_(Tensor_id));
+  luaT_registeratname(L, nn_(SoftPlus__), "nn");
+  lua_pop(L,1);
+}
+
+#endif