added missing ts.Lstsq API

tensor/patch.go

@@ -560,3 +560,31 @@ func MustWhere(condition Tensor, del bool) (retVal []Tensor) {
 
 	return retVal
 }
+
+// NOTE. patches for APIs `agt_` missing in tensor/ but existing in lib
+// ====================================================================
+
+// void atg_lstsq(tensor *, tensor self, tensor A);
+func (ts *Tensor) Lstsq(a *ts.Tensor, del bool) (retVal *Tensor, err error) {
+	if del {
+		defer ts.MustDrop()
+	}
+	ptr := (*lib.Ctensor)(unsafe.Pointer(C.malloc(0)))
+
+	lib.AtgLstsq(ptr, ts.ctensor, a.ctensor)
+	if err = TorchErr(); err != nil {
+		return retVal, err
+	}
+	retVal = &Tensor{ctensor: *ptr}
+
+	return retVal, err
+}
+
+func (ts *Tensor) MustLstsq(a *ts.Tensor, del bool) (retVal *Tensor) {
+	retVal, err := ts.Lstsq(del)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	return retVal
+}