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Nova/src/spartan/mod.rs
src/spartan/mod.rsRaw
  1//! This module implements RelaxedR1CSSNARKTrait using Spartan that is generic
  2//! over the polynomial commitment and evaluation argument (i.e., a PCS)
  3mod math;
  4pub(crate) mod polynomial;
  5pub mod pp;
  6mod sumcheck;
  7
  8use crate::{
  9  errors::NovaError,
 10  r1cs::{R1CSShape, RelaxedR1CSInstance, RelaxedR1CSWitness},
 11  traits::{
 12    evaluation::EvaluationEngineTrait, snark::RelaxedR1CSSNARKTrait, Group, TranscriptEngineTrait,
 13  },
 14  Commitment, CommitmentKey,
 15};
 16use ff::Field;
 17use itertools::concat;
 18use polynomial::{EqPolynomial, MultilinearPolynomial, SparsePolynomial};
 19use rayon::prelude::*;
 20use serde::{Deserialize, Serialize};
 21use sumcheck::SumcheckProof;
 22
 23fn powers<G: Group>(s: &G::Scalar, n: usize) -> Vec<G::Scalar> {
 24  assert!(n >= 1);
 25  let mut powers = Vec::new();
 26  powers.push(G::Scalar::ONE);
 27  for i in 1..n {
 28    powers.push(powers[i - 1] * s);
 29  }
 30  powers
 31}
 32
 33/// A type that holds a witness to a polynomial evaluation instance
 34pub struct PolyEvalWitness<G: Group> {
 35  p: Vec<G::Scalar>, // polynomial
 36}
 37
 38impl<G: Group> PolyEvalWitness<G> {
 39  fn pad(W: &[PolyEvalWitness<G>]) -> Vec<PolyEvalWitness<G>> {
 40    // determine the maximum size
 41    if let Some(n) = W.iter().map(|w| w.p.len()).max() {
 42      W.iter()
 43        .map(|w| {
 44          let mut p = w.p.clone();
 45          p.resize(n, G::Scalar::ZERO);
 46          PolyEvalWitness { p }
 47        })
 48        .collect()
 49    } else {
 50      Vec::new()
 51    }
 52  }
 53
 54  fn weighted_sum(W: &[PolyEvalWitness<G>], s: &[G::Scalar]) -> PolyEvalWitness<G> {
 55    assert_eq!(W.len(), s.len());
 56    let mut p = vec![G::Scalar::ZERO; W[0].p.len()];
 57    for i in 0..W.len() {
 58      for j in 0..W[i].p.len() {
 59        p[j] += W[i].p[j] * s[i]
 60      }
 61    }
 62    PolyEvalWitness { p }
 63  }
 64
 65  fn batch(p_vec: &[&Vec<G::Scalar>], s: &G::Scalar) -> PolyEvalWitness<G> {
 66    let powers_of_s = powers::<G>(s, p_vec.len());
 67    let mut p = vec![G::Scalar::ZERO; p_vec[0].len()];
 68    for i in 0..p_vec.len() {
 69      for (j, item) in p.iter_mut().enumerate().take(p_vec[i].len()) {
 70        *item += p_vec[i][j] * powers_of_s[i]
 71      }
 72    }
 73    PolyEvalWitness { p }
 74  }
 75}
 76
 77/// A type that holds a polynomial evaluation instance
 78pub struct PolyEvalInstance<G: Group> {
 79  c: Commitment<G>,  // commitment to the polynomial
 80  x: Vec<G::Scalar>, // evaluation point
 81  e: G::Scalar,      // claimed evaluation
 82}
 83
 84impl<G: Group> PolyEvalInstance<G> {
 85  fn pad(U: &[PolyEvalInstance<G>]) -> Vec<PolyEvalInstance<G>> {
 86    // determine the maximum size
 87    if let Some(ell) = U.iter().map(|u| u.x.len()).max() {
 88      U.iter()
 89        .map(|u| {
 90          let mut x = vec![G::Scalar::ZERO; ell - u.x.len()];
 91          x.extend(u.x.clone());
 92          PolyEvalInstance { c: u.c, x, e: u.e }
 93        })
 94        .collect()
 95    } else {
 96      Vec::new()
 97    }
 98  }
 99
100  fn batch(
101    c_vec: &[Commitment<G>],
102    x: &[G::Scalar],
103    e_vec: &[G::Scalar],
104    s: &G::Scalar,
105  ) -> PolyEvalInstance<G> {
106    let powers_of_s = powers::<G>(s, c_vec.len());
107    let e = e_vec
108      .iter()
109      .zip(powers_of_s.iter())
110      .map(|(e, p)| *e * p)
111      .fold(G::Scalar::ZERO, |acc, item| acc + item);
112    let c = c_vec
113      .iter()
114      .zip(powers_of_s.iter())
115      .map(|(c, p)| *c * *p)
116      .fold(Commitment::<G>::default(), |acc, item| acc + item);
117
118    PolyEvalInstance {
119      c,
120      x: x.to_vec(),
121      e,
122    }
123  }
124}
125
126/// A type that represents the prover's key
127#[derive(Serialize, Deserialize)]
128#[serde(bound = "")]
129pub struct ProverKey<G: Group, EE: EvaluationEngineTrait<G, CE = G::CE>> {
130  pk_ee: EE::ProverKey,
131  S: R1CSShape<G>,
132}
133
134/// A type that represents the verifier's key
135#[derive(Serialize, Deserialize)]
136#[serde(bound = "")]
137pub struct VerifierKey<G: Group, EE: EvaluationEngineTrait<G, CE = G::CE>> {
138  vk_ee: EE::VerifierKey,
139  S: R1CSShape<G>,
140}
141
142/// A succinct proof of knowledge of a witness to a relaxed R1CS instance
143/// The proof is produced using Spartan's combination of the sum-check and
144/// the commitment to a vector viewed as a polynomial commitment
145#[derive(Serialize, Deserialize)]
146#[serde(bound = "")]
147pub struct RelaxedR1CSSNARK<G: Group, EE: EvaluationEngineTrait<G, CE = G::CE>> {
148  sc_proof_outer: SumcheckProof<G>,
149  claims_outer: (G::Scalar, G::Scalar, G::Scalar),
150  eval_E: G::Scalar,
151  sc_proof_inner: SumcheckProof<G>,
152  eval_W: G::Scalar,
153  sc_proof_batch: SumcheckProof<G>,
154  evals_batch: Vec<G::Scalar>,
155  eval_arg: EE::EvaluationArgument,
156}
157
158impl<G: Group, EE: EvaluationEngineTrait<G, CE = G::CE>> RelaxedR1CSSNARKTrait<G>
159  for RelaxedR1CSSNARK<G, EE>
160{
161  type ProverKey = ProverKey<G, EE>;
162  type VerifierKey = VerifierKey<G, EE>;
163
164  fn setup(
165    ck: &CommitmentKey<G>,
166    S: &R1CSShape<G>,
167  ) -> Result<(Self::ProverKey, Self::VerifierKey), NovaError> {
168    let (pk_ee, vk_ee) = EE::setup(ck);
169
170    let S = S.pad();
171
172    let vk = VerifierKey {
173      vk_ee,
174      S: S.clone(),
175    };
176
177    let pk = ProverKey { pk_ee, S };
178
179    Ok((pk, vk))
180  }
181
182  /// produces a succinct proof of satisfiability of a RelaxedR1CS instance
183  fn prove(
184    ck: &CommitmentKey<G>,
185    pk: &Self::ProverKey,
186    U: &RelaxedR1CSInstance<G>,
187    W: &RelaxedR1CSWitness<G>,
188  ) -> Result<Self, NovaError> {
189    let W = W.pad(&pk.S); // pad the witness
190    let mut transcript = G::TE::new(b"RelaxedR1CSSNARK");
191
192    // sanity check that R1CSShape has certain size characteristics
193    assert_eq!(pk.S.num_cons.next_power_of_two(), pk.S.num_cons);
194    assert_eq!(pk.S.num_vars.next_power_of_two(), pk.S.num_vars);
195    assert_eq!(pk.S.num_io.next_power_of_two(), pk.S.num_io);
196    assert!(pk.S.num_io < pk.S.num_vars);
197
198    // append the digest of R1CS matrices and the RelaxedR1CSInstance to the transcript
199    transcript.absorb(b"S", &pk.S);
200    transcript.absorb(b"U", U);
201
202    // compute the full satisfying assignment by concatenating W.W, U.u, and U.X
203    let mut z = concat(vec![W.W.clone(), vec![U.u], U.X.clone()]);
204
205    let (num_rounds_x, num_rounds_y) = (
206      (pk.S.num_cons as f64).log2() as usize,
207      ((pk.S.num_vars as f64).log2() as usize + 1),
208    );
209
210    // outer sum-check
211    let tau = (0..num_rounds_x)
212      .map(|_i| transcript.squeeze(b"t"))
213      .collect::<Result<Vec<G::Scalar>, NovaError>>()?;
214
215    let mut poly_tau = MultilinearPolynomial::new(EqPolynomial::new(tau).evals());
216    let (mut poly_Az, mut poly_Bz, poly_Cz, mut poly_uCz_E) = {
217      let (poly_Az, poly_Bz, poly_Cz) = pk.S.multiply_vec(&z)?;
218      let poly_uCz_E = (0..pk.S.num_cons)
219        .map(|i| U.u * poly_Cz[i] + W.E[i])
220        .collect::<Vec<G::Scalar>>();
221      (
222        MultilinearPolynomial::new(poly_Az),
223        MultilinearPolynomial::new(poly_Bz),
224        MultilinearPolynomial::new(poly_Cz),
225        MultilinearPolynomial::new(poly_uCz_E),
226      )
227    };
228
229    let comb_func_outer =
230      |poly_A_comp: &G::Scalar,
231       poly_B_comp: &G::Scalar,
232       poly_C_comp: &G::Scalar,
233       poly_D_comp: &G::Scalar|
234       -> G::Scalar { *poly_A_comp * (*poly_B_comp * *poly_C_comp - *poly_D_comp) };
235    let (sc_proof_outer, r_x, claims_outer) = SumcheckProof::prove_cubic_with_additive_term(
236      &G::Scalar::ZERO, // claim is zero
237      num_rounds_x,
238      &mut poly_tau,
239      &mut poly_Az,
240      &mut poly_Bz,
241      &mut poly_uCz_E,
242      comb_func_outer,
243      &mut transcript,
244    )?;
245
246    // claims from the end of sum-check
247    let (claim_Az, claim_Bz): (G::Scalar, G::Scalar) = (claims_outer[1], claims_outer[2]);
248    let claim_Cz = poly_Cz.evaluate(&r_x);
249    let eval_E = MultilinearPolynomial::new(W.E.clone()).evaluate(&r_x);
250    transcript.absorb(
251      b"claims_outer",
252      &[claim_Az, claim_Bz, claim_Cz, eval_E].as_slice(),
253    );
254
255    // inner sum-check
256    let r = transcript.squeeze(b"r")?;
257    let claim_inner_joint = claim_Az + r * claim_Bz + r * r * claim_Cz;
258
259    let poly_ABC = {
260      // compute the initial evaluation table for R(\tau, x)
261      let evals_rx = EqPolynomial::new(r_x.clone()).evals();
262
263      // Bounds "row" variables of (A, B, C) matrices viewed as 2d multilinear polynomials
264      let compute_eval_table_sparse =
265        |S: &R1CSShape<G>, rx: &[G::Scalar]| -> (Vec<G::Scalar>, Vec<G::Scalar>, Vec<G::Scalar>) {
266          assert_eq!(rx.len(), S.num_cons);
267
268          let inner = |M: &Vec<(usize, usize, G::Scalar)>, M_evals: &mut Vec<G::Scalar>| {
269            for (row, col, val) in M {
270              M_evals[*col] += rx[*row] * val;
271            }
272          };
273
274          let (A_evals, (B_evals, C_evals)) = rayon::join(
275            || {
276              let mut A_evals: Vec<G::Scalar> = vec![G::Scalar::ZERO; 2 * S.num_vars];
277              inner(&S.A, &mut A_evals);
278              A_evals
279            },
280            || {
281              rayon::join(
282                || {
283                  let mut B_evals: Vec<G::Scalar> = vec![G::Scalar::ZERO; 2 * S.num_vars];
284                  inner(&S.B, &mut B_evals);
285                  B_evals
286                },
287                || {
288                  let mut C_evals: Vec<G::Scalar> = vec![G::Scalar::ZERO; 2 * S.num_vars];
289                  inner(&S.C, &mut C_evals);
290                  C_evals
291                },
292              )
293            },
294          );
295
296          (A_evals, B_evals, C_evals)
297        };
298
299      let (evals_A, evals_B, evals_C) = compute_eval_table_sparse(&pk.S, &evals_rx);
300
301      assert_eq!(evals_A.len(), evals_B.len());
302      assert_eq!(evals_A.len(), evals_C.len());
303      (0..evals_A.len())
304        .into_par_iter()
305        .map(|i| evals_A[i] + r * evals_B[i] + r * r * evals_C[i])
306        .collect::<Vec<G::Scalar>>()
307    };
308
309    let poly_z = {
310      z.resize(pk.S.num_vars * 2, G::Scalar::ZERO);
311      z
312    };
313
314    let comb_func = |poly_A_comp: &G::Scalar, poly_B_comp: &G::Scalar| -> G::Scalar {
315      *poly_A_comp * *poly_B_comp
316    };
317    let (sc_proof_inner, r_y, _claims_inner) = SumcheckProof::prove_quad(
318      &claim_inner_joint,
319      num_rounds_y,
320      &mut MultilinearPolynomial::new(poly_ABC),
321      &mut MultilinearPolynomial::new(poly_z),
322      comb_func,
323      &mut transcript,
324    )?;
325
326    // add additional claims about W and E polynomials to the list from CC
327    let mut w_u_vec = Vec::new();
328    let eval_W = MultilinearPolynomial::evaluate_with(&W.W, &r_y[1..]);
329    w_u_vec.push((
330      PolyEvalWitness { p: W.W.clone() },
331      PolyEvalInstance {
332        c: U.comm_W,
333        x: r_y[1..].to_vec(),
334        e: eval_W,
335      },
336    ));
337
338    w_u_vec.push((
339      PolyEvalWitness { p: W.E },
340      PolyEvalInstance {
341        c: U.comm_E,
342        x: r_x,
343        e: eval_E,
344      },
345    ));
346
347    // We will now reduce a vector of claims of evaluations at different points into claims about them at the same point.
348    // For example, eval_W =? W(r_y[1..]) and eval_W =? E(r_x) into
349    // two claims: eval_W_prime =? W(rz) and eval_E_prime =? E(rz)
350    // We can them combine the two into one: eval_W_prime + gamma * eval_E_prime =? (W + gamma*E)(rz),
351    // where gamma is a public challenge
352    // Since commitments to W and E are homomorphic, the verifier can compute a commitment
353    // to the batched polynomial.
354    assert!(w_u_vec.len() >= 2);
355
356    let (w_vec, u_vec): (Vec<PolyEvalWitness<G>>, Vec<PolyEvalInstance<G>>) =
357      w_u_vec.into_iter().unzip();
358    let w_vec_padded = PolyEvalWitness::pad(&w_vec); // pad the polynomials to be of the same size
359    let u_vec_padded = PolyEvalInstance::pad(&u_vec); // pad the evaluation points
360
361    // generate a challenge
362    let rho = transcript.squeeze(b"r")?;
363    let num_claims = w_vec_padded.len();
364    let powers_of_rho = powers::<G>(&rho, num_claims);
365    let claim_batch_joint = u_vec_padded
366      .iter()
367      .zip(powers_of_rho.iter())
368      .map(|(u, p)| u.e * p)
369      .fold(G::Scalar::ZERO, |acc, item| acc + item);
370
371    let mut polys_left: Vec<MultilinearPolynomial<G::Scalar>> = w_vec_padded
372      .iter()
373      .map(|w| MultilinearPolynomial::new(w.p.clone()))
374      .collect();
375    let mut polys_right: Vec<MultilinearPolynomial<G::Scalar>> = u_vec_padded
376      .iter()
377      .map(|u| MultilinearPolynomial::new(EqPolynomial::new(u.x.clone()).evals()))
378      .collect();
379
380    let num_rounds_z = u_vec_padded[0].x.len();
381    let comb_func = |poly_A_comp: &G::Scalar, poly_B_comp: &G::Scalar| -> G::Scalar {
382      *poly_A_comp * *poly_B_comp
383    };
384    let (sc_proof_batch, r_z, claims_batch) = SumcheckProof::prove_quad_batch(
385      &claim_batch_joint,
386      num_rounds_z,
387      &mut polys_left,
388      &mut polys_right,
389      &powers_of_rho,
390      comb_func,
391      &mut transcript,
392    )?;
393
394    let (claims_batch_left, _): (Vec<G::Scalar>, Vec<G::Scalar>) = claims_batch;
395
396    transcript.absorb(b"l", &claims_batch_left.as_slice());
397
398    // we now combine evaluation claims at the same point rz into one
399    let gamma = transcript.squeeze(b"g")?;
400    let powers_of_gamma: Vec<G::Scalar> = powers::<G>(&gamma, num_claims);
401    let comm_joint = u_vec_padded
402      .iter()
403      .zip(powers_of_gamma.iter())
404      .map(|(u, g_i)| u.c * *g_i)
405      .fold(Commitment::<G>::default(), |acc, item| acc + item);
406    let poly_joint = PolyEvalWitness::weighted_sum(&w_vec_padded, &powers_of_gamma);
407    let eval_joint = claims_batch_left
408      .iter()
409      .zip(powers_of_gamma.iter())
410      .map(|(e, g_i)| *e * *g_i)
411      .fold(G::Scalar::ZERO, |acc, item| acc + item);
412
413    let eval_arg = EE::prove(
414      ck,
415      &pk.pk_ee,
416      &mut transcript,
417      &comm_joint,
418      &poly_joint.p,
419      &r_z,
420      &eval_joint,
421    )?;
422
423    Ok(RelaxedR1CSSNARK {
424      sc_proof_outer,
425      claims_outer: (claim_Az, claim_Bz, claim_Cz),
426      eval_E,
427      sc_proof_inner,
428      eval_W,
429      sc_proof_batch,
430      evals_batch: claims_batch_left,
431      eval_arg,
432    })
433  }
434
435  /// verifies a proof of satisfiability of a RelaxedR1CS instance
436  fn verify(&self, vk: &Self::VerifierKey, U: &RelaxedR1CSInstance<G>) -> Result<(), NovaError> {
437    let mut transcript = G::TE::new(b"RelaxedR1CSSNARK");
438
439    // append the digest of R1CS matrices and the RelaxedR1CSInstance to the transcript
440    transcript.absorb(b"S", &vk.S);
441    transcript.absorb(b"U", U);
442
443    let (num_rounds_x, num_rounds_y) = (
444      (vk.S.num_cons as f64).log2() as usize,
445      ((vk.S.num_vars as f64).log2() as usize + 1),
446    );
447
448    // outer sum-check
449    let tau = (0..num_rounds_x)
450      .map(|_i| transcript.squeeze(b"t"))
451      .collect::<Result<Vec<G::Scalar>, NovaError>>()?;
452
453    let (claim_outer_final, r_x) =
454      self
455        .sc_proof_outer
456        .verify(G::Scalar::ZERO, num_rounds_x, 3, &mut transcript)?;
457
458    // verify claim_outer_final
459    let (claim_Az, claim_Bz, claim_Cz) = self.claims_outer;
460    let taus_bound_rx = EqPolynomial::new(tau).evaluate(&r_x);
461    let claim_outer_final_expected =
462      taus_bound_rx * (claim_Az * claim_Bz - U.u * claim_Cz - self.eval_E);
463    if claim_outer_final != claim_outer_final_expected {
464      return Err(NovaError::InvalidSumcheckProof);
465    }
466
467    transcript.absorb(
468      b"claims_outer",
469      &[
470        self.claims_outer.0,
471        self.claims_outer.1,
472        self.claims_outer.2,
473        self.eval_E,
474      ]
475      .as_slice(),
476    );
477
478    // inner sum-check
479    let r = transcript.squeeze(b"r")?;
480    let claim_inner_joint =
481      self.claims_outer.0 + r * self.claims_outer.1 + r * r * self.claims_outer.2;
482
483    let (claim_inner_final, r_y) =
484      self
485        .sc_proof_inner
486        .verify(claim_inner_joint, num_rounds_y, 2, &mut transcript)?;
487
488    // verify claim_inner_final
489    let eval_Z = {
490      let eval_X = {
491        // constant term
492        let mut poly_X = vec![(0, U.u)];
493        //remaining inputs
494        poly_X.extend(
495          (0..U.X.len())
496            .map(|i| (i + 1, U.X[i]))
497            .collect::<Vec<(usize, G::Scalar)>>(),
498        );
499        SparsePolynomial::new((vk.S.num_vars as f64).log2() as usize, poly_X).evaluate(&r_y[1..])
500      };
501      (G::Scalar::ONE - r_y[0]) * self.eval_W + r_y[0] * eval_X
502    };
503
504    // compute evaluations of R1CS matrices
505    let multi_evaluate = |M_vec: &[&[(usize, usize, G::Scalar)]],
506                          r_x: &[G::Scalar],
507                          r_y: &[G::Scalar]|
508     -> Vec<G::Scalar> {
509      let evaluate_with_table =
510        |M: &[(usize, usize, G::Scalar)], T_x: &[G::Scalar], T_y: &[G::Scalar]| -> G::Scalar {
511          (0..M.len())
512            .collect::<Vec<usize>>()
513            .par_iter()
514            .map(|&i| {
515              let (row, col, val) = M[i];
516              T_x[row] * T_y[col] * val
517            })
518            .reduce(|| G::Scalar::ZERO, |acc, x| acc + x)
519        };
520
521      let (T_x, T_y) = rayon::join(
522        || EqPolynomial::new(r_x.to_vec()).evals(),
523        || EqPolynomial::new(r_y.to_vec()).evals(),
524      );
525
526      (0..M_vec.len())
527        .collect::<Vec<usize>>()
528        .par_iter()
529        .map(|&i| evaluate_with_table(M_vec[i], &T_x, &T_y))
530        .collect()
531    };
532
533    let evals = multi_evaluate(&[&vk.S.A, &vk.S.B, &vk.S.C], &r_x, &r_y);
534
535    let claim_inner_final_expected = (evals[0] + r * evals[1] + r * r * evals[2]) * eval_Z;
536    if claim_inner_final != claim_inner_final_expected {
537      return Err(NovaError::InvalidSumcheckProof);
538    }
539
540    // add claims about W and E polynomials
541    let u_vec: Vec<PolyEvalInstance<G>> = vec![
542      PolyEvalInstance {
543        c: U.comm_W,
544        x: r_y[1..].to_vec(),
545        e: self.eval_W,
546      },
547      PolyEvalInstance {
548        c: U.comm_E,
549        x: r_x,
550        e: self.eval_E,
551      },
552    ];
553
554    let u_vec_padded = PolyEvalInstance::pad(&u_vec); // pad the evaluation points
555
556    // generate a challenge
557    let rho = transcript.squeeze(b"r")?;
558    let num_claims = u_vec.len();
559    let powers_of_rho = powers::<G>(&rho, num_claims);
560    let claim_batch_joint = u_vec
561      .iter()
562      .zip(powers_of_rho.iter())
563      .map(|(u, p)| u.e * p)
564      .fold(G::Scalar::ZERO, |acc, item| acc + item);
565
566    let num_rounds_z = u_vec_padded[0].x.len();
567    let (claim_batch_final, r_z) =
568      self
569        .sc_proof_batch
570        .verify(claim_batch_joint, num_rounds_z, 2, &mut transcript)?;
571
572    let claim_batch_final_expected = {
573      let poly_rz = EqPolynomial::new(r_z.clone());
574      let evals = u_vec_padded
575        .iter()
576        .map(|u| poly_rz.evaluate(&u.x))
577        .collect::<Vec<G::Scalar>>();
578
579      evals
580        .iter()
581        .zip(self.evals_batch.iter())
582        .zip(powers_of_rho.iter())
583        .map(|((e_i, p_i), rho_i)| *e_i * *p_i * rho_i)
584        .fold(G::Scalar::ZERO, |acc, item| acc + item)
585    };
586
587    if claim_batch_final != claim_batch_final_expected {
588      return Err(NovaError::InvalidSumcheckProof);
589    }
590
591    transcript.absorb(b"l", &self.evals_batch.as_slice());
592
593    // we now combine evaluation claims at the same point rz into one
594    let gamma = transcript.squeeze(b"g")?;
595    let powers_of_gamma: Vec<G::Scalar> = powers::<G>(&gamma, num_claims);
596    let comm_joint = u_vec_padded
597      .iter()
598      .zip(powers_of_gamma.iter())
599      .map(|(u, g_i)| u.c * *g_i)
600      .fold(Commitment::<G>::default(), |acc, item| acc + item);
601    let eval_joint = self
602      .evals_batch
603      .iter()
604      .zip(powers_of_gamma.iter())
605      .map(|(e, g_i)| *e * *g_i)
606      .fold(G::Scalar::ZERO, |acc, item| acc + item);
607
608    // verify
609    EE::verify(
610      &vk.vk_ee,
611      &mut transcript,
612      &comm_joint,
613      &r_z,
614      &eval_joint,
615      &self.eval_arg,
616    )?;
617
618    Ok(())
619  }
620}