refactor(gamma): big decimal

Author: cong-or

src/audit/src/offline/bin/main.rs

@@ -37,10 +37,10 @@ pub struct Args {
     /// cross reference official results
     #[clap(short, long)]
     official_results: Option<String>,
-    /// Quadratic scaling
+    /// Gamma value for Quadratic scaling
     #[clap(short, long)]
     gamma: Option<String>,
-    /// Quadratic scaling
+    /// Rounding precision for arithmetic
     #[clap(short, long)]
     precision: Option<String>,
 }
@@ -103,8 +103,8 @@ fn main() -> Result<(), Box<dyn Error>> {
     let shares_and_results = extract_decryption_shares_and_results(all_fragments);
 
     if let Some(gamma) = args.gamma {
-        const SCALE_FACTOR: &str = "QUADRATIC_VOTING_SCALING_FACTOR";
-        std::env::set_var(SCALE_FACTOR, gamma);
+        const GAMMA: &str = "QUADRATIC_VOTING_GAMMA";
+        std::env::set_var(GAMMA, gamma);
     }
 
     if let Some(precision) = args.precision {

src/chain-libs/chain-impl-mockchain/src/vote/tally.rs

@@ -173,14 +173,14 @@ impl TallyResult {
         } else {
             let index = choice.as_byte() as usize;
 
-            const SCALE_FACTOR: &str = "QUADRATIC_VOTING_SCALING_FACTOR";
+            const GAMMA: &str = "QUADRATIC_VOTING_GAMMA";
             const PRECISION: &str = "QUADRATIC_VOTING_PRECISION";
 
-            let scaling_factor = env::var(SCALE_FACTOR).unwrap_or(1.to_string());
+            let gamma = env::var(GAMMA).unwrap_or(1.to_string());
             let precision =
                 i64::from_str(&env::var(PRECISION).unwrap_or(1.to_string())).unwrap_or(1);
 
-            let gamma = BigDecimal::from_str(&scaling_factor).unwrap_or(BigDecimal::from(1));
+            let gamma = BigDecimal::from_str(&gamma).unwrap_or(BigDecimal::from(1));
             let stake = BigDecimal::from(weight.0);
 
             let weight = (gamma * stake)

src/chain-libs/chain-vote/src/tally.rs

@@ -165,13 +165,13 @@ impl EncryptedTally {
         assert_eq!(ballot.vote().len(), self.r.len());
         assert_eq!(ballot.fingerprint(), &self.fingerprint);
 
-        const SCALE_FACTOR: &str = "QUADRATIC_VOTING_SCALING_FACTOR";
+        const GAMMA: &str = "QUADRATIC_VOTING_GAMMA";
         const PRECISION: &str = "QUADRATIC_VOTING_PRECISION";
 
-        let scaling_factor = env::var(SCALE_FACTOR).unwrap_or(1.to_string());
+        let gamma = env::var(GAMMA).unwrap_or(1.to_string());
         let precision = i64::from_str(&env::var(PRECISION).unwrap_or(1.to_string())).unwrap_or(1);
 
-        let gamma = BigDecimal::from_str(&scaling_factor).unwrap_or(BigDecimal::from(1));
+        let gamma = BigDecimal::from_str(&gamma).unwrap_or(BigDecimal::from(1));
         let stake = BigDecimal::from(weight);
 
         let weight = (gamma * stake).round(precision).to_u64().unwrap_or(weight);