Merge branch 'master' into fix-mode-gamma

Author: YeungOnion

.github/workflows/test.yml

@@ -6,34 +6,55 @@ on:
   pull_request:
     branches: [ master ]
 
+env:
+  CARGO_INCREMENTAL: 0
+  RUSTFLAGS: "-Dwarnings"
+
 jobs:
+  clippy:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Install Rust stable with clippy
+        uses: dtolnay/rust-toolchain@stable
+        with:
+          components: clippy
+
+      - name: Run cargo clippy
+        run: cargo clippy --all-targets
+
+  fmt:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Install Rust nightly with rustfmt
+        uses: dtolnay/rust-toolchain@nightly
+        with:
+          components: rustfmt
+
+      - name: Run rustfmt --check
+        run: cargo fmt -- --check
+
   test:
-    name: Test
+    needs: [clippy, fmt]
     runs-on: ${{ matrix.os }}
     strategy:
-      fail-fast: false
       matrix:
-        include:
-          - os: ubuntu-latest
-            target: x86_64-unknown-linux-gnu
-            toolchain: stable
-          - os: ubuntu-latest
-            target: x86_64-unknown-linux-gnu
-            toolchain: nightly
+          os: [ubuntu-latest, macos-latest, windows-latest]
+          toolchain: [stable, nightly]
+
     steps:
-      - uses: actions/checkout@v2
-      - name: Install toolchain
-        uses: actions-rs/toolchain@v1
+      - uses: actions/checkout@v4
+      - name: Install Rust ${{ matrix.toolchain }}
+        uses: dtolnay/rust-toolchain@master
         with:
-          profile: minimal
-          target: ${{ matrix.target }}
           toolchain: ${{ matrix.toolchain }}
-          override: true
-      - name: Test nightly feature (if possible)
-        if: ${{ matrix.toolchain == 'nightly' }}
-        run: |
-          cargo test --target ${{ matrix.target }} --features=nightly
-          cargo test --target ${{ matrix.target }} --benches --features=nightly
+
+      - name: Test nightly feature
+        if: matrix.toolchain == 'nightly'
+        run: cargo test --all-targets --features=nightly
+
       - name: Test default features
-        run: |
-          cargo test --target ${{ matrix.target }}
+        if: matrix.toolchain != 'nightly'
+        run: cargo test --all-targets
+

src/distribution/bernoulli.rs

@@ -257,7 +257,7 @@ impl Discrete<u64, f64> for Bernoulli {
 }
 
 #[rustfmt::skip]
-#[cfg(all(test, feature = "nightly"))]
+#[cfg(test)]
 mod testing {
     use std::fmt::Debug;
     use crate::distribution::DiscreteCDF;

src/distribution/cauchy.rs

@@ -432,7 +432,7 @@ mod tests {
         test_almost(0.0, 0.1, 0.9936346508990272, 1e-16, sf(-5.0));
         test_almost(0.0, 0.1, 0.9682744825694465, 1e-16, sf(-1.0));
         test_case(0.0, 0.1, 0.5, sf(0.0));
-        test_case(0.0, 0.1, 0.03172551743055352, sf(1.0));
+        test_almost(0.0, 0.1, 0.03172551743055352, 1e-16, sf(1.0));
         test_case(0.0, 0.1, 0.006365349100972806, sf(5.0));
         test_almost(0.0, 1.0, 0.9371670418109989, 1e-16, sf(-5.0));
         test_case(0.0, 1.0, 0.75, sf(-1.0));

src/distribution/dirac.rs

@@ -185,7 +185,7 @@ impl Mode<Option<f64>> for Dirac {
 }
 
 #[rustfmt::skip]
-#[cfg(all(test, feature = "nightly"))]
+#[cfg(test)]
 mod tests {
     use crate::statistics::*;
     use crate::distribution::{ContinuousCDF, Continuous, Dirac};

src/distribution/dirichlet.rs

@@ -301,7 +301,7 @@ fn is_valid_alpha(a: &[f64]) -> bool {
 }
 
 #[rustfmt::skip]
-#[cfg(all(test, feature = "nightly"))]
+#[cfg(test)]
 mod tests {
     use super::*;
     use nalgebra::{DVector};

src/distribution/discrete_uniform.rs

@@ -248,7 +248,7 @@ impl Discrete<i64, f64> for DiscreteUniform {
 }
 
 #[rustfmt::skip]
-#[cfg(all(test, feature = "nightly"))]
+#[cfg(test)]
 mod tests {
     use std::fmt::Debug;
     use crate::statistics::*;

src/distribution/empirical.rs

@@ -206,7 +206,7 @@ impl ContinuousCDF<f64, f64> for Empirical {
     }
 }
 
-#[cfg(all(test, feature = "nightly"))]
+#[cfg(test)]
 mod tests {
     use super::*;
     #[test]

src/distribution/laplace.rs

@@ -291,7 +291,7 @@ impl Continuous<f64, f64> for Laplace {
     }
 }
 
-#[cfg(all(test, feature = "nightly"))]
+#[cfg(test)]
 mod tests {
     use super::*;
     use rand::thread_rng;

src/distribution/multivariate_normal.rs

@@ -242,7 +242,7 @@ impl Continuous<Vec<f64>, f64> for MultivariateNormal {
 }
 
 #[rustfmt::skip]
-#[cfg(all(test, feature = "nightly"))]
+#[cfg(test)]
 mod tests  {
     use crate::distribution::{Continuous, MultivariateNormal};
     use crate::statistics::*;

src/distribution/normal.rs

@@ -51,6 +51,24 @@ impl Normal {
             Ok(Normal { mean, std_dev })
         }
     }
+
+    /// Constructs a new standard normal distribution with a mean of 0
+    /// and a standard deviation of 1.
+    ///
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use statrs::distribution::Normal;
+    ///
+    /// let mut result = Normal::standard();
+    /// ```
+    pub fn standard() -> Normal {
+        Normal {
+            mean: 0.0,
+            std_dev: 1.0,
+        }
+    }
 }
 
 impl ::rand::distributions::Distribution<f64> for Normal {
@@ -292,6 +310,15 @@ pub fn sample_unchecked<R: Rng + ?Sized>(rng: &mut R, mean: f64, std_dev: f64) -
     mean + std_dev * ziggurat::sample_std_normal(rng)
 }
 
+
+impl std::default::Default for Normal {
+    /// Returns the standard normal distribution with a mean of 0
+    /// and a standard deviation of 1.
+    fn default() -> Self {
+        Self::standard()
+    }
+}
+
 #[rustfmt::skip]
 #[cfg(all(test, feature = "nightly"))]
 mod tests {
@@ -512,4 +539,17 @@ mod tests {
         test_almost(5.0, 2.0, 10.0, 1e-14, inverse_cdf(0.9937903346742238648330218954258077788721022530769078));
         test_case(5.0, 2.0, f64::INFINITY, inverse_cdf(1.0));
     }
+
+    #[test]
+    fn test_default() {
+        let n = Normal::default();
+
+        let n_mean = n.mean().unwrap();
+        let n_std  = n.std_dev().unwrap();
+
+        // Check that the mean of the distribution is close to 0
+        assert_almost_eq!(n_mean, 0.0, 1e-15);
+        // Check that the standard deviation of the distribution is close to 1
+        assert_almost_eq!(n_std, 1.0, 1e-15);
+    }
 }