fix: sampling should use DistIter, but not collect it

Author: YeungOnion

examples/random_clap.rs

@@ -159,24 +159,24 @@ fn run_command_sample(count: Option<usize>, dist: DistributionAsCommand) -> Resu
     match dist {
         // multinomial should print `count` of Vec<uint>
         DistributionAsCommand::Multinomial { n, p } => {
-            let samples = thread_rng().sample_iter(Multinomial::new(p, n)?);
+            let sample_iter = thread_rng().sample_iter(Multinomial::new(p, n)?);
             print_multivariate_samples(
                 count,
-                samples.map(|v: na::DVector<u64>| {
+                sample_iter.map(|v: na::DVector<u64>| {
                     let vec: Vec<_> = v.into_iter().cloned().collect();
                     vec
                 }),
             )?;
         }
         // binomial should print `count` of uint
         DistributionAsCommand::Binomial { n, p } => {
-            let samples: Vec<u64> = thread_rng().sample_iter(Binomial::new(p, n)?).collect();
-            print_samples(count, samples)?;
+            let sample_iter = thread_rng().sample_iter::<u64, Binomial>(Binomial::new(p, n)?);
+            print_samples(count, sample_iter)?;
         }
         // normal should print `count` of float
         DistributionAsCommand::Normal { mu, sigma } => {
-            let samples = thread_rng().sample_iter(Normal::new(mu, sigma)?);
-            print_samples(count, samples)?
+            let sample_iter = thread_rng().sample_iter(Normal::new(mu, sigma)?);
+            print_samples(count, sample_iter)?
         }
     }