@@ -1,3 +1,4 @@
+use crate::ffi::vec_znx;
 use crate::znx_base::ZnxInfos;
 use crate::{
     Backend, DataView, DataViewMut, Module, VecZnx, VecZnxToMut, VecZnxToRef, ZnxSliceSize, ZnxView, ZnxViewMut, alloc_aligned,
@@ -119,6 +120,69 @@ ScalarZnxOwned::new::<i64>(self.n(), cols)
     }
     fn new_scalar_znx_from_bytes(&self, cols: usize, bytes: Vec<u8>) -> ScalarZnxOwned {
         ScalarZnxOwned::new_from_bytes::<i64>(self.n(), cols, bytes)
+    }
+}
+
+pub trait ScalarZnxOps {
+    fn scalar_znx_automorphism<R, A>(&self, k: i64, res: &mut R, res_col: usize, a: &A, a_col: usize)
+    where
+        R: ScalarZnxToMut,
+        A: ScalarZnxToRef;
+
+    /// Applies the automorphism X^i -> X^ik on the selected column of `a`.
+    fn vec_znx_automorphism_inplace<A>(&self, k: i64, a: &mut A, a_col: usize)
+    where
+        A: ScalarZnxToMut;
+}
+
+impl<B: Backend> ScalarZnxOps for Module<B> {
+    fn scalar_znx_automorphism<R, A>(&self, k: i64, res: &mut R, res_col: usize, a: &A, a_col: usize)
+    where
+        R: ScalarZnxToMut,
+        A: ScalarZnxToRef,
+    {
+        let a: ScalarZnx<&[u8]> = a.to_ref();
+        let mut res: ScalarZnx<&mut [u8]> = res.to_mut();
+        #[cfg(debug_assertions)]
+        {
+            assert_eq!(a.n(), self.n());
+            assert_eq!(res.n(), self.n());
+        }
+        unsafe {
+            vec_znx::vec_znx_automorphism(
+                self.ptr,
+                k,
+                res.at_mut_ptr(res_col, 0),
+                res.size() as u64,
+                res.sl() as u64,
+                a.at_ptr(a_col, 0),
+                a.size() as u64,
+                a.sl() as u64,
+            )
+        }
+    }
+
+    fn vec_znx_automorphism_inplace<A>(&self, k: i64, a: &mut A, a_col: usize)
+    where
+        A: ScalarZnxToMut,
+    {
+        let mut a: ScalarZnx<&mut [u8]> = a.to_mut();
+        #[cfg(debug_assertions)]
+        {
+            assert_eq!(a.n(), self.n());
+        }
+        unsafe {
+            vec_znx::vec_znx_automorphism(
+                self.ptr,
+                k,
+                a.at_mut_ptr(a_col, 0),
+                a.size() as u64,
+                a.sl() as u64,
+                a.at_ptr(a_col, 0),
+                a.size() as u64,
+                a.sl() as u64,
+            )
+        }
     }
 }
 

@@ -0,0 +1,253 @@
+use base2k::{
+    Backend, FFT64, MatZnxDft, MatZnxDftOps, MatZnxDftToMut, MatZnxDftToRef, Module, ScalarZnx, ScalarZnxDftOps, ScalarZnxOps,
+    ScalarZnxToRef, Scratch, VecZnxDft, VecZnxDftToMut, VecZnxDftToRef,
+};
+use sampling::source::Source;
+
+use crate::{
+    elem::{GetRow, Infos, SetRow},
+    gglwe_ciphertext::GGLWECiphertext,
+    ggsw_ciphertext::GGSWCiphertext,
+    glwe_ciphertext_fourier::GLWECiphertextFourier,
+    keys::{SecretKey, SecretKeyFourier},
+    keyswitch_key::GLWESwitchingKey,
+};
+
+pub struct AutomorphismKey<Data, B: Backend> {
+    pub(crate) key: GLWESwitchingKey<Data, B>,
+    pub(crate) p: i64,
+}
+
+impl AutomorphismKey<Vec<u8>, FFT64> {
+    pub fn new(module: &Module<FFT64>, basek: usize, p: i64, k: usize, rows: usize, rank: usize) -> Self {
+        AutomorphismKey {
+            key: GLWESwitchingKey::new(module, basek, k, rows, rank, rank),
+            p: p,
+        }
+    }
+}
+
+impl<T, B: Backend> Infos for AutomorphismKey<T, B> {
+    type Inner = MatZnxDft<T, B>;
+
+    fn inner(&self) -> &Self::Inner {
+        &self.key.inner()
+    }
+
+    fn basek(&self) -> usize {
+        self.key.basek()
+    }
+
+    fn k(&self) -> usize {
+        self.key.k()
+    }
+}
+
+impl<T, B: Backend> AutomorphismKey<T, B> {
+    pub fn p(&self) -> i64 {
+        self.p
+    }
+
+    pub fn rank(&self) -> usize {
+        self.key.rank()
+    }
+
+    pub fn rank_in(&self) -> usize {
+        self.key.rank_in()
+    }
+
+    pub fn rank_out(&self) -> usize {
+        self.key.rank_out()
+    }
+}
+
+impl<DataSelf, B: Backend> MatZnxDftToMut<B> for AutomorphismKey<DataSelf, B>
+where
+    MatZnxDft<DataSelf, B>: MatZnxDftToMut<B>,
+{
+    fn to_mut(&mut self) -> MatZnxDft<&mut [u8], B> {
+        self.key.to_mut()
+    }
+}
+
+impl<DataSelf, B: Backend> MatZnxDftToRef<B> for AutomorphismKey<DataSelf, B>
+where
+    MatZnxDft<DataSelf, B>: MatZnxDftToRef<B>,
+{
+    fn to_ref(&self) -> MatZnxDft<&[u8], B> {
+        self.key.to_ref()
+    }
+}
+
+impl<C> GetRow<FFT64> for AutomorphismKey<C, FFT64>
+where
+    MatZnxDft<C, FFT64>: MatZnxDftToRef<FFT64>,
+{
+    fn get_row<R>(&self, module: &Module<FFT64>, row_i: usize, col_j: usize, res: &mut GLWECiphertextFourier<R, FFT64>)
+    where
+        VecZnxDft<R, FFT64>: VecZnxDftToMut<FFT64>,
+    {
+        module.vmp_extract_row(res, self, row_i, col_j);
+    }
+}
+
+impl<C> SetRow<FFT64> for AutomorphismKey<C, FFT64>
+where
+    MatZnxDft<C, FFT64>: MatZnxDftToMut<FFT64>,
+{
+    fn set_row<R>(&mut self, module: &Module<FFT64>, row_i: usize, col_j: usize, a: &GLWECiphertextFourier<R, FFT64>)
+    where
+        VecZnxDft<R, FFT64>: VecZnxDftToRef<FFT64>,
+    {
+        module.vmp_prepare_row(self, row_i, col_j, a);
+    }
+}
+
+impl AutomorphismKey<Vec<u8>, FFT64> {
+    pub fn encrypt_sk_scratch_space(module: &Module<FFT64>, rank: usize, size: usize) -> usize {
+        GGLWECiphertext::encrypt_sk_scratch_space(module, rank, size)
+    }
+
+    pub fn encrypt_pk_scratch_space(module: &Module<FFT64>, rank: usize, pk_size: usize) -> usize {
+        GGLWECiphertext::encrypt_pk_scratch_space(module, rank, pk_size)
+    }
+
+    pub fn keyswitch_scratch_space(
+        module: &Module<FFT64>,
+        out_size: usize,
+        in_size: usize,
+        ksk_size: usize,
+        rank: usize,
+    ) -> usize {
+        GLWESwitchingKey::keyswitch_scratch_space(module, out_size, rank, in_size, rank, ksk_size)
+    }
+
+    pub fn keyswitch_inplace_scratch_space(module: &Module<FFT64>, out_size: usize, out_rank: usize, ksk_size: usize) -> usize {
+        GLWESwitchingKey::keyswitch_inplace_scratch_space(module, out_size, out_rank, ksk_size)
+    }
+
+    pub fn external_product_scratch_space(
+        module: &Module<FFT64>,
+        out_size: usize,
+        in_size: usize,
+        ggsw_size: usize,
+        rank: usize,
+    ) -> usize {
+        GLWESwitchingKey::external_product_scratch_space(module, out_size, in_size, ggsw_size, rank)
+    }
+
+    pub fn external_product_inplace_scratch_space(
+        module: &Module<FFT64>,
+        out_size: usize,
+        ggsw_size: usize,
+        rank: usize,
+    ) -> usize {
+        GLWESwitchingKey::external_product_inplace_scratch_space(module, out_size, ggsw_size, rank)
+    }
+}
+
+impl<DataSelf> AutomorphismKey<DataSelf, FFT64>
+where
+    MatZnxDft<DataSelf, FFT64>: MatZnxDftToMut<FFT64> + MatZnxDftToRef<FFT64>,
+{
+    pub fn encrypt_sk<DataSk>(
+        &mut self,
+        module: &Module<FFT64>,
+        p: i64,
+        sk: &SecretKey<DataSk>,
+        source_xa: &mut Source,
+        source_xe: &mut Source,
+        sigma: f64,
+        scratch: &mut Scratch,
+    ) where
+        ScalarZnx<DataSk>: ScalarZnxToRef,
+    {
+        #[cfg(debug_assertions)]
+        {
+            assert_eq!(self.n(), module.n());
+            assert_eq!(sk.n(), module.n());
+            assert_eq!(self.rank_out(), self.rank_in());
+            assert_eq!(sk.rank(), self.rank());
+        }
+
+        let (sk_out_dft_data, scratch_1) = scratch.tmp_scalar_znx_dft(module, sk.rank());
+
+        let mut sk_out_dft: SecretKeyFourier<&mut [u8], FFT64> = SecretKeyFourier {
+            data: sk_out_dft_data,
+            dist: sk.dist,
+        };
+
+        {
+            (0..self.rank()).for_each(|i| {
+                let (mut sk_inv_auto, _) = scratch_1.tmp_scalar_znx(module, 1);
+                module.scalar_znx_automorphism(module.galois_element_inv(p), &mut sk_inv_auto, 0, sk, i);
+                module.svp_prepare(&mut sk_out_dft, i, &sk_inv_auto, 0);
+            });
+        }
+
+        self.key.encrypt_sk(
+            module,
+            &sk,
+            &sk_out_dft,
+            source_xa,
+            source_xe,
+            sigma,
+            scratch_1,
+        );
+
+        self.p = p;
+    }
+}
+
+impl<DataSelf> AutomorphismKey<DataSelf, FFT64>
+where
+    MatZnxDft<DataSelf, FFT64>: MatZnxDftToMut<FFT64> + MatZnxDftToRef<FFT64>,
+{
+    pub fn keyswitch<DataLhs, DataRhs>(
+        &mut self,
+        module: &Module<FFT64>,
+        lhs: &AutomorphismKey<DataLhs, FFT64>,
+        rhs: &GLWESwitchingKey<DataRhs, FFT64>,
+        scratch: &mut base2k::Scratch,
+    ) where
+        MatZnxDft<DataLhs, FFT64>: MatZnxDftToRef<FFT64>,
+        MatZnxDft<DataRhs, FFT64>: MatZnxDftToRef<FFT64>,
+    {
+        self.key.keyswitch(module, &lhs.key, rhs, scratch);
+    }
+
+    pub fn keyswitch_inplace<DataRhs>(
+        &mut self,
+        module: &Module<FFT64>,
+        rhs: &AutomorphismKey<DataRhs, FFT64>,
+        scratch: &mut base2k::Scratch,
+    ) where
+        MatZnxDft<DataRhs, FFT64>: MatZnxDftToRef<FFT64>,
+    {
+        self.key.keyswitch_inplace(module, &rhs.key, scratch);
+    }
+
+    pub fn external_product<DataLhs, DataRhs>(
+        &mut self,
+        module: &Module<FFT64>,
+        lhs: &AutomorphismKey<DataLhs, FFT64>,
+        rhs: &GGSWCiphertext<DataRhs, FFT64>,
+        scratch: &mut Scratch,
+    ) where
+        MatZnxDft<DataLhs, FFT64>: MatZnxDftToRef<FFT64>,
+        MatZnxDft<DataRhs, FFT64>: MatZnxDftToRef<FFT64>,
+    {
+        self.key.external_product(module, &lhs.key, rhs, scratch);
+    }
+
+    pub fn external_product_inplace<DataRhs>(
+        &mut self,
+        module: &Module<FFT64>,
+        rhs: &GGSWCiphertext<DataRhs, FFT64>,
+        scratch: &mut Scratch,
+    ) where
+        MatZnxDft<DataRhs, FFT64>: MatZnxDftToRef<FFT64>,
+    {
+        self.key.external_product_inplace(module, rhs, scratch);
+    }
+}

@@ -21,10 +21,10 @@ pub(crate) k: usize,
 }
 
 impl<B: Backend> GGLWECiphertext<Vec<u8>, B> {
-    pub fn new(module: &Module<B>, base2k: usize, k: usize, rows: usize, rank_in: usize, rank_out: usize) -> Self {
+    pub fn new(module: &Module<B>, basek: usize, k: usize, rows: usize, rank_in: usize, rank_out: usize) -> Self {
         Self {
-            data: module.new_mat_znx_dft(rows, rank_in, rank_out + 1, derive_size(base2k, k)),
-            basek: base2k,
+            data: module.new_mat_znx_dft(rows, rank_in, rank_out + 1, derive_size(basek, k)),
+            basek: basek,
             k,
         }
     }
@@ -161,6 +161,7 @@ // (-(b*s) + s1, b)
         (0..cols_in).for_each(|col_i| {
             (0..rows).for_each(|row_i| {
                 // Adds the scalar_znx_pt to the i-th limb of the vec_znx_pt
+                vec_znx_pt.data.zero(); // zeroes for next iteration
                 module.vec_znx_add_scalar_inplace(&mut vec_znx_pt, 0, row_i, pt, col_i); // Selects the i-th
                 module.vec_znx_normalize_inplace(basek, &mut vec_znx_pt, 0, scratch_3);
 
@@ -174,8 +175,6 @@ source_xe,
                     sigma,
                     scratch_3,
                 );
-
-                vec_znx_pt.data.zero(); // zeroes for next iteration
 
                 // Switch vec_znx_ct into DFT domain
                 vec_znx_ct.dft(module, &mut vec_znx_ct_dft);

@@ -8,6 +8,7 @@ use sampling::source::Source;
 
 use crate::{
     SIX_SIGMA,
+    automorphism::AutomorphismKey,
     elem::Infos,
     ggsw_ciphertext::GGSWCiphertext,
     glwe_ciphertext_fourier::GLWECiphertextFourier,
@@ -137,21 +138,40 @@ pub fn keyswitch_inplace_scratch_space(module: &Module<FFT64>, out_size: usize, out_rank: usize, ksk_size: usize) -> usize {
         GLWECiphertext::keyswitch_scratch_space(module, out_size, out_rank, out_size, out_rank, ksk_size)
     }
 
+    pub fn automorphism_scratch_space(
+        module: &Module<FFT64>,
+        out_size: usize,
+        out_rank: usize,
+        in_size: usize,
+        autokey_size: usize,
+    ) -> usize {
+        GLWECiphertext::keyswitch_scratch_space(module, out_size, out_rank, in_size, out_rank, autokey_size)
+    }
+
+    pub fn automorphism_inplace_scratch_space(
+        module: &Module<FFT64>,
+        out_size: usize,
+        out_rank: usize,
+        autokey_size: usize,
+    ) -> usize {
+        GLWECiphertext::keyswitch_scratch_space(module, out_size, out_rank, out_size, out_rank, autokey_size)
+    }
+
     pub fn external_product_scratch_space(
         module: &Module<FFT64>,
         out_size: usize,
+        out_rank: usize,
         in_size: usize,
         ggsw_size: usize,
-        rank: usize,
     ) -> usize {
-        let res_dft: usize = module.bytes_of_vec_znx_dft(rank + 1, ggsw_size);
-        let vmp: usize = module.bytes_of_vec_znx_dft(rank + 1, in_size)
+        let res_dft: usize = module.bytes_of_vec_znx_dft(out_rank + 1, ggsw_size);
+        let vmp: usize = module.bytes_of_vec_znx_dft(out_rank + 1, in_size)
             + module.vmp_apply_tmp_bytes(
                 out_size,
                 in_size,
-                in_size,  // rows
-                rank + 1, // cols in
-                rank + 1, // cols out
+                in_size,      // rows
+                out_rank + 1, // cols in
+                out_rank + 1, // cols out
                 ggsw_size,
             );
         let normalize: usize = module.vec_znx_big_normalize_tmp_bytes();
@@ -159,8 +179,13 @@
         res_dft + (vmp | normalize)
     }
 
-    pub fn external_product_inplace_scratch_space(module: &Module<FFT64>, res_size: usize, rhs: usize, rank: usize) -> usize {
-        GLWECiphertext::external_product_scratch_space(module, res_size, res_size, rhs, rank)
+    pub fn external_product_inplace_scratch_space(
+        module: &Module<FFT64>,
+        out_size: usize,
+        out_rank: usize,
+        ggsw_size: usize,
+    ) -> usize {
+        GLWECiphertext::external_product_scratch_space(module, out_size, out_rank, out_size, ggsw_size)
     }
 }
 
@@ -242,6 +267,36 @@ ) where
         VecZnxDft<DataPk, FFT64>: VecZnxDftToRef<FFT64>,
     {
         self.encrypt_pk_private(module, None, pk, source_xu, source_xe, sigma, scratch);
+    }
+
+    pub fn automorphism<DataLhs, DataRhs>(
+        &mut self,
+        module: &Module<FFT64>,
+        lhs: &GLWECiphertext<DataLhs>,
+        rhs: &AutomorphismKey<DataRhs, FFT64>,
+        scratch: &mut Scratch,
+    ) where
+        VecZnx<DataLhs>: VecZnxToRef,
+        MatZnxDft<DataRhs, FFT64>: MatZnxDftToRef<FFT64>,
+    {
+        self.keyswitch(module, lhs, &rhs.key, scratch);
+        //(0..self.rank() + 1).for_each(|i| {
+        //    module.vec_znx_automorphism_inplace(rhs.p(), self, i);
+        //})
+    }
+
+    pub fn automorphism_inplace<DataRhs>(
+        &mut self,
+        module: &Module<FFT64>,
+        rhs: &AutomorphismKey<DataRhs, FFT64>,
+        scratch: &mut Scratch,
+    ) where
+        MatZnxDft<DataRhs, FFT64>: MatZnxDftToRef<FFT64>,
+    {
+        self.keyswitch_inplace(module, &rhs.key, scratch);
+        (0..self.rank() + 1).for_each(|i| {
+            module.vec_znx_automorphism_inplace(rhs.p(), self, i);
+        })
     }
 
     pub fn keyswitch<DataLhs, DataRhs>(

@@ -15,9 +15,9 @@
 pub struct GLWESwitchingKey<Data, B: Backend>(pub(crate) GGLWECiphertext<Data, B>);
 
 impl GLWESwitchingKey<Vec<u8>, FFT64> {
-    pub fn new(module: &Module<FFT64>, base2k: usize, k: usize, rows: usize, rank_in: usize, rank_out: usize) -> Self {
+    pub fn new(module: &Module<FFT64>, basek: usize, k: usize, rows: usize, rank_in: usize, rank_out: usize) -> Self {
         GLWESwitchingKey(GGLWECiphertext::new(
-            module, base2k, k, rows, rank_in, rank_out,
+            module, basek, k, rows, rank_in, rank_out,
         ))
     }
 }
@@ -26,7 +26,7 @@ impl<T, B: Backend> Infos for GLWESwitchingKey<T, B> {
     type Inner = MatZnxDft<T, B>;
 
     fn inner(&self) -> &Self::Inner {
-        &self.0.inner()
+        self.0.inner()
     }
 
     fn basek(&self) -> usize {
@@ -102,38 +102,7 @@
     pub fn encrypt_pk_scratch_space(module: &Module<FFT64>, rank: usize, pk_size: usize) -> usize {
         GGLWECiphertext::encrypt_pk_scratch_space(module, rank, pk_size)
     }
-}
 
-impl<DataSelf> GLWESwitchingKey<DataSelf, FFT64>
-where
-    MatZnxDft<DataSelf, FFT64>: MatZnxDftToMut<FFT64> + MatZnxDftToRef<FFT64>,
-{
-    pub fn encrypt_sk<DataSkIn, DataSkOut>(
-        &mut self,
-        module: &Module<FFT64>,
-        sk_in: &SecretKey<DataSkIn>,
-        sk_out_dft: &SecretKeyFourier<DataSkOut, FFT64>,
-        source_xa: &mut Source,
-        source_xe: &mut Source,
-        sigma: f64,
-        scratch: &mut Scratch,
-    ) where
-        ScalarZnx<DataSkIn>: ScalarZnxToRef,
-        ScalarZnxDft<DataSkOut, FFT64>: ScalarZnxDftToRef<FFT64>,
-    {
-        self.0.encrypt_sk(
-            module,
-            &sk_in.data,
-            sk_out_dft,
-            source_xa,
-            source_xe,
-            sigma,
-            scratch,
-        );
-    }
-}
-
-impl GLWESwitchingKey<Vec<u8>, FFT64> {
     pub fn keyswitch_scratch_space(
         module: &Module<FFT64>,
         out_size: usize,
@@ -178,11 +147,34 @@ let ggsw: usize = GLWECiphertextFourier::external_product_inplace_scratch_space(module, out_size, ggsw_size, rank);
         tmp + ggsw
     }
 }
-
 impl<DataSelf> GLWESwitchingKey<DataSelf, FFT64>
 where
     MatZnxDft<DataSelf, FFT64>: MatZnxDftToMut<FFT64> + MatZnxDftToRef<FFT64>,
 {
+    pub fn encrypt_sk<DataSkIn, DataSkOut>(
+        &mut self,
+        module: &Module<FFT64>,
+        sk_in: &SecretKey<DataSkIn>,
+        sk_out_dft: &SecretKeyFourier<DataSkOut, FFT64>,
+        source_xa: &mut Source,
+        source_xe: &mut Source,
+        sigma: f64,
+        scratch: &mut Scratch,
+    ) where
+        ScalarZnx<DataSkIn>: ScalarZnxToRef,
+        ScalarZnxDft<DataSkOut, FFT64>: ScalarZnxDftToRef<FFT64>,
+    {
+        self.0.encrypt_sk(
+            module,
+            &sk_in.data,
+            sk_out_dft,
+            source_xa,
+            source_xe,
+            sigma,
+            scratch,
+        );
+    }
+
     pub fn keyswitch<DataLhs, DataRhs>(
         &mut self,
         module: &Module<FFT64>,

@@ -1,3 +1,4 @@
+pub mod automorphism;
 pub mod elem;
 pub mod gglwe_ciphertext;
 pub mod ggsw_ciphertext;

@@ -6,6 +6,7 @@ use itertools::izip;
 use sampling::source::Source;
 
 use crate::{
+    automorphism::AutomorphismKey,
     elem::Infos,
     ggsw_ciphertext::GGSWCiphertext,
     glwe_ciphertext::GLWECiphertext,
@@ -405,6 +406,114 @@ 0f64,
         rank as f64,
         k_ct,
         k_ksk,
+    );
+
+    assert!(
+        (noise_have - noise_want).abs() <= 0.1,
+        "{} {}",
+        noise_have,
+        noise_want
+    );
+}
+
+#[test]
+fn automorphism() {
+    (1..4).for_each(|rank| {
+        println!("test automorphism rank: {}", rank);
+        test_automorphism(12, 12, 1, 60, 45, 60, rank, 3.2);
+    });
+}
+
+fn test_automorphism(
+    log_n: usize,
+    basek: usize,
+    p: i64,
+    k_autokey: usize,
+    k_ct_in: usize,
+    k_ct_out: usize,
+    rank: usize,
+    sigma: f64,
+) {
+    let module: Module<FFT64> = Module::<FFT64>::new(1 << log_n);
+    let rows: usize = (k_ct_in + basek - 1) / basek;
+
+    let mut autokey: AutomorphismKey<Vec<u8>, FFT64> = AutomorphismKey::new(&module, basek, p, k_autokey, rows, rank);
+    let mut ct_in: GLWECiphertext<Vec<u8>> = GLWECiphertext::new(&module, basek, k_ct_in, rank);
+    let mut ct_out: GLWECiphertext<Vec<u8>> = GLWECiphertext::new(&module, basek, k_ct_out, rank);
+    let mut pt_want: GLWEPlaintext<Vec<u8>> = GLWEPlaintext::new(&module, basek, k_ct_in);
+    let mut pt_have: GLWEPlaintext<Vec<u8>> = GLWEPlaintext::new(&module, basek, k_ct_out);
+
+    let mut source_xs: Source = Source::new([0u8; 32]);
+    let mut source_xe: Source = Source::new([0u8; 32]);
+    let mut source_xa: Source = Source::new([0u8; 32]);
+
+    // Random input plaintext
+    // pt_want
+    // .data
+    // .fill_uniform(basek, 0, pt_want.size(), &mut source_xa);
+
+    pt_want
+        .to_mut()
+        .at_mut(0, 1)
+        .iter_mut()
+        .enumerate()
+        .for_each(|(i, x)| {
+            *x = i as i64;
+        });
+
+    let mut scratch: ScratchOwned = ScratchOwned::new(
+        GLWESwitchingKey::encrypt_sk_scratch_space(&module, rank, autokey.size())
+            | GLWECiphertext::decrypt_scratch_space(&module, ct_out.size())
+            | GLWECiphertext::encrypt_sk_scratch_space(&module, ct_in.size())
+            | GLWECiphertext::automorphism_scratch_space(&module, ct_out.size(), rank, ct_in.size(), autokey.size()),
+    );
+
+    let mut sk: SecretKey<Vec<u8>> = SecretKey::new(&module, rank);
+    sk.fill_ternary_prob(0.5, &mut source_xs);
+
+    let mut sk_dft: SecretKeyFourier<Vec<u8>, FFT64> = SecretKeyFourier::new(&module, rank);
+    sk_dft.dft(&module, &sk);
+
+    autokey.encrypt_sk(
+        &module,
+        p,
+        &sk,
+        &mut source_xa,
+        &mut source_xe,
+        sigma,
+        scratch.borrow(),
+    );
+
+    ct_in.encrypt_sk(
+        &module,
+        &pt_want,
+        &sk_dft,
+        &mut source_xa,
+        &mut source_xe,
+        sigma,
+        scratch.borrow(),
+    );
+
+    ct_out.automorphism(&module, &ct_in, &autokey, scratch.borrow());
+
+    ct_out.decrypt(&module, &mut pt_have, &sk_dft, scratch.borrow());
+
+    module.vec_znx_automorphism_inplace(p, &mut pt_want, 0);
+
+    module.vec_znx_sub_ab_inplace(&mut pt_have, 0, &pt_want, 0);
+
+    let noise_have: f64 = pt_have.data.std(0, basek).log2();
+    let noise_want: f64 = noise_gglwe_product(
+        module.n() as f64,
+        basek,
+        0.5,
+        0.5,
+        0f64,
+        sigma * sigma,
+        0f64,
+        rank as f64,
+        k_ct_in,
+        k_autokey,
     );
 
     assert!(