feat: 添加 CROSET 和 CROSEW 模块

- croset: 使用 FREQ 数组设置光致电离截面
- crosew: 使用 FREQC 数组设置光致电离截面
- 支持普通能级和溶解能级 (INDEXP=5)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/math/crosew.rs

@@ -0,0 +1,414 @@
+//! 光致电离截面数组设置。
+//!
+//! 重构自 SYNSPEC `CROSET` 和 `CROSEW` 函数。
+//!
+//! # 功能
+//!
+//! 设置光致电离截面数组，用于辐射转移计算。
+
+use super::sigk::{sigk, SigkParams};
+use crate::state::atomic::AtomicData;
+use crate::state::constants::{MCROSS, MFREQ};
+
+// ============================================================================
+// 常量
+// ============================================================================
+
+/// INDEXP 值表示溶解能级（需要特殊处理）
+const INDEXP_DISSOLVED: i32 = 5;
+
+// ============================================================================
+// CROSET - 使用 FREQ 数组设置截面
+// ============================================================================
+
+/// CROSET 输入参数。
+pub struct CrosetParams<'a> {
+    /// 频率数组 (FREQ)
+    pub freq: &'a [f64],
+    /// 能级数 (NLEVEL)
+    pub nlevel: usize,
+    /// 频率数 (NFREQ)
+    pub nfreq: usize,
+    /// 模式 (IMODE)
+    pub imode: i32,
+    /// INDEXP 数组 - 能级索引类型
+    pub indexp: &'a [i32],
+    /// FROPC 数组 - 阈值频率
+    pub fropc: &'a [f64],
+    /// 原子数据引用
+    pub atomic: &'a AtomicData,
+}
+
+/// 设置光致电离截面数组 (使用 FREQ)。
+///
+/// # 参数
+///
+/// * `params` - 输入参数
+///
+/// # 返回值
+///
+/// CROSS 数组 [MCROSS][MFREQ]，其中 CROSS[itr][ij] 是能级 itr 在频率 ij 处的截面
+///
+/// # Fortran 原始代码
+///
+/// ```fortran
+/// SUBROUTINE CROSET(CROSS)
+///   IJ0=2
+///   IF(NFREQ.EQ.1) IJ0=1
+///   IF(IMODE.EQ.2) IJ0=NFREQ
+///   DO IJ=1,IJ0
+///      DO IT=1,MCROSS
+///         CROSS(IT,IJ)=0.
+///      END DO
+///   END DO
+///   DO IT=1,NLEVEL
+///      IF(INDEXP(IT).NE.5) THEN
+///         DO IJ=1,IJ0
+///            FR=FREQ(IJ)
+///            CROSS(IT,IJ)=SIGK(FR,IT,0)
+///         END DO
+///      ELSE
+///         DO IJ=1,IJ0
+///            FR=FREQ(IJ)
+///            CROSS(IT,IJ)=SIGK(FR,IT,1)
+///            IF(FR.LT.FROPC(IT)) CROSS(IT,IJ)=0.
+///         END DO
+///      END IF
+///   END DO
+/// END
+/// ```
+pub fn croset(params: &CrosetParams) -> Vec<Vec<f64>> {
+    let CrosetParams {
+        freq,
+        nlevel,
+        nfreq,
+        imode,
+        indexp,
+        fropc,
+        atomic,
+    } = *params;
+
+    // 确定频率范围
+    // Fortran: IJ0=2; IF(NFREQ.EQ.1) IJ0=1; IF(IMODE.EQ.2) IJ0=NFREQ
+    let ij0 = if nfreq == 1 {
+        1
+    } else if imode == 2 {
+        nfreq
+    } else {
+        2
+    };
+
+    // 初始化截面数组
+    // 注意：Fortran 是 1-indexed，Rust 是 0-indexed
+    let mut cross = vec![vec![0.0; ij0]; nlevel];
+
+    // 计算每个能级在每个频率处的截面
+    for it in 0..nlevel {
+        let idxp = indexp[it];
+
+        if idxp != INDEXP_DISSOLVED {
+            // 普通能级：mode = 0（边缘长波方向截面为零）
+            for ij in 0..ij0 {
+                let fr = freq[ij];
+                let sigk_params = SigkParams {
+                    fr,
+                    itr: it,
+                    mode: 0,
+                    atomic,
+                    opdata: &super::topbas::OpData::default(),
+                };
+                cross[it][ij] = sigk(&sigk_params);
+            }
+        } else {
+            // 溶解能级：mode = 1（边缘长波方向截面非零）
+            for ij in 0..ij0 {
+                let fr = freq[ij];
+                let sigk_params = SigkParams {
+                    fr,
+                    itr: it,
+                    mode: 1,
+                    atomic,
+                    opdata: &super::topbas::OpData::default(),
+                };
+                cross[it][ij] = sigk(&sigk_params);
+
+                // 如果频率低于阈值，截面设为零
+                // Fortran: IF(FR.LT.FROPC(IT)) CROSS(IT,IJ)=0.
+                if fr < fropc[it] {
+                    cross[it][ij] = 0.0;
+                }
+            }
+        }
+    }
+
+    cross
+}
+
+// ============================================================================
+// CROSEW - 使用 FREQC 数组设置截面
+// ============================================================================
+
+/// CROSEW 输入参数。
+pub struct CrosewParams<'a> {
+    /// 频率数组 (FREQC)
+    pub freqc: &'a [f64],
+    /// 能级数 (NLEVEL)
+    pub nlevel: usize,
+    /// 频率数 (NFREQC)
+    pub nfreqc: usize,
+    /// INDEXP 数组 - 能级索引类型
+    pub indexp: &'a [i32],
+    /// FROPC 数组 - 阈值频率
+    pub fropc: &'a [f64],
+    /// 原子数据引用
+    pub atomic: &'a AtomicData,
+}
+
+/// 设置光致电离截面数组 (使用 FREQC)。
+///
+/// # 参数
+///
+/// * `params` - 输入参数
+///
+/// # 返回值
+///
+/// CROSS 数组 [MCROSS][MFREQC]
+///
+/// # Fortran 原始代码
+///
+/// ```fortran
+/// SUBROUTINE CROSEW(CROSS)
+///   IJ0=NFREQC
+///   DO IJ=1,IJ0
+///      DO IT=1,MCROSS
+///         CROSS(IT,IJ)=0.
+///      END DO
+///   END DO
+///   DO IT=1,NLEVEL
+///      IF(INDEXP(IT).NE.5) THEN
+///         DO IJ=1,IJ0
+///            FR=FREQC(IJ)
+///            CROSS(IT,IJ)=SIGK(FR,IT,0)
+///         END DO
+///      ELSE
+///         DO IJ=1,IJ0
+///            FR=FREQC(IJ)
+///            CROSS(IT,IJ)=SIGK(FR,IT,1)
+///            IF(FR.LT.FROPC(IT)) CROSS(IT,IJ)=0.
+///         END DO
+///      END IF
+///   END DO
+/// END
+/// ```
+pub fn crosew(params: &CrosewParams) -> Vec<Vec<f64>> {
+    let CrosewParams {
+        freqc,
+        nlevel,
+        nfreqc,
+        indexp,
+        fropc,
+        atomic,
+    } = *params;
+
+    // 初始化截面数组
+    let mut cross = vec![vec![0.0; nfreqc]; nlevel];
+
+    // 计算每个能级在每个频率处的截面
+    for it in 0..nlevel {
+        let idxp = indexp[it];
+
+        if idxp != INDEXP_DISSOLVED {
+            // 普通能级：mode = 0
+            for ij in 0..nfreqc {
+                let fr = freqc[ij];
+                let sigk_params = SigkParams {
+                    fr,
+                    itr: it,
+                    mode: 0,
+                    atomic,
+                    opdata: &super::topbas::OpData::default(),
+                };
+                cross[it][ij] = sigk(&sigk_params);
+            }
+        } else {
+            // 溶解能级：mode = 1
+            for ij in 0..nfreqc {
+                let fr = freqc[ij];
+                let sigk_params = SigkParams {
+                    fr,
+                    itr: it,
+                    mode: 1,
+                    atomic,
+                    opdata: &super::topbas::OpData::default(),
+                };
+                cross[it][ij] = sigk(&sigk_params);
+
+                // 如果频率低于阈值，截面设为零
+                if fr < fropc[it] {
+                    cross[it][ij] = 0.0;
+                }
+            }
+        }
+    }
+
+    cross
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::state::atomic::AtomicData;
+
+    fn create_test_atomic() -> AtomicData {
+        let mut atomic = AtomicData::new();
+
+        // 设置能级参数
+        atomic.phoset.ibf[0] = 0; // 氢原子，Gaunt = 1
+        atomic.phoset.ibf[1] = 0;
+        atomic.phoset.ibf[2] = 0;
+
+        // 设置电离能 (转换为频率)
+        // H I 电离能 = 13.6 eV = 2.1785e-11 erg
+        // 频率 = E/h = 2.1785e-11 / 6.6256e-27 = 3.288e15 Hz
+        atomic.levpar.enion[0] = 3.288e15 * 6.6256e-27; // Hz * h = erg
+        atomic.levpar.enion[1] = 3.288e15 * 6.6256e-27;
+        atomic.levpar.enion[2] = 3.288e15 * 6.6256e-27;
+
+        // 设置主量子数
+        atomic.levpar.nquant[0] = 1;
+        atomic.levpar.nquant[1] = 2;
+        atomic.levpar.nquant[2] = 3;
+
+        atomic
+    }
+
+    #[test]
+    fn test_croset_basic() {
+        let atomic = create_test_atomic();
+
+        // 创建频率数组（在电离阈值之上）
+        let freq = vec![4.0e15, 5.0e15, 6.0e15];
+        let indexp = vec![0, 0, 0]; // 普通能级
+        let fropc = vec![0.0; 3];
+
+        let params = CrosetParams {
+            freq: &freq,
+            nlevel: 3,
+            nfreq: 3,
+            imode: 0,
+            indexp: &indexp,
+            fropc: &fropc,
+            atomic: &atomic,
+        };
+
+        let cross = croset(&params);
+
+        // 验证数组大小
+        assert_eq!(cross.len(), 3);
+        // ij0 = 2 (因为 nfreq != 1 且 imode != 2)
+        assert_eq!(cross[0].len(), 2);
+    }
+
+    #[test]
+    fn test_croset_single_freq() {
+        let atomic = create_test_atomic();
+
+        let freq = vec![4.0e15];
+        let indexp = vec![0];
+        let fropc = vec![0.0];
+
+        let params = CrosetParams {
+            freq: &freq,
+            nlevel: 1,
+            nfreq: 1,
+            imode: 0,
+            indexp: &indexp,
+            fropc: &fropc,
+            atomic: &atomic,
+        };
+
+        let cross = croset(&params);
+
+        // 当 nfreq = 1 时，ij0 = 1
+        assert_eq!(cross.len(), 1);
+        assert_eq!(cross[0].len(), 1);
+    }
+
+    #[test]
+    fn test_croset_imode_2() {
+        let atomic = create_test_atomic();
+
+        let freq = vec![4.0e15, 5.0e15, 6.0e15];
+        let indexp = vec![0, 0, 0];
+        let fropc = vec![0.0; 3];
+
+        let params = CrosetParams {
+            freq: &freq,
+            nlevel: 3,
+            nfreq: 3,
+            imode: 2, // 使用所有频率
+            indexp: &indexp,
+            fropc: &fropc,
+            atomic: &atomic,
+        };
+
+        let cross = croset(&params);
+
+        // 当 imode = 2 时，ij0 = nfreq = 3
+        assert_eq!(cross.len(), 3);
+        assert_eq!(cross[0].len(), 3);
+    }
+
+    #[test]
+    fn test_crosew_basic() {
+        let atomic = create_test_atomic();
+
+        let freqc = vec![4.0e15, 5.0e15, 6.0e15];
+        let indexp = vec![0, 0, 0];
+        let fropc = vec![0.0; 3];
+
+        let params = CrosewParams {
+            freqc: &freqc,
+            nlevel: 3,
+            nfreqc: 3,
+            indexp: &indexp,
+            fropc: &fropc,
+            atomic: &atomic,
+        };
+
+        let cross = crosew(&params);
+
+        // 验证数组大小
+        assert_eq!(cross.len(), 3);
+        assert_eq!(cross[0].len(), 3);
+    }
+
+    #[test]
+    fn test_crosew_dissolved_level() {
+        let atomic = create_test_atomic();
+
+        let freqc = vec![4.0e15, 5.0e15];
+        // INDEXP = 5 表示溶解能级
+        let indexp = vec![5, 0];
+        // 设置阈值频率
+        let fropc = vec![3.5e15, 0.0];
+
+        let params = CrosewParams {
+            freqc: &freqc,
+            nlevel: 2,
+            nfreqc: 2,
+            indexp: &indexp,
+            fropc: &fropc,
+            atomic: &atomic,
+        };
+
+        let cross = crosew(&params);
+
+        // 验证数组大小
+        assert_eq!(cross.len(), 2);
+        assert_eq!(cross[0].len(), 2);
+
+        // 能级 0 是溶解能级，频率 > fropc[0]，所以截面应该非零
+        // 注意：实际值取决于 SIGK 的实现
+    }
+}

src/math/mod.rs

@@ -56,6 +56,7 @@ mod convec;
 mod coolrt;
 mod count_words;
 mod cross;
+mod crosew;
 mod cspec;
 mod ctdata;
 mod cubic;
@@ -353,6 +354,7 @@ pub use convec::{convec, convc1, ConvecConfig, ConvecParams, ConvecOutput, Convc
 pub use coolrt::{coolrt_pure, CoolrtParams, CoolrtOutput, compute_taud, find_fe2_ion};
 pub use count_words::count_words;
 pub use cross::{cross, crossd};
+pub use crosew::{croset, crosew, CrosetParams, CrosewParams};
 pub use cspec::cspec;
 pub use ctdata::{hction, hctrecom, CTION, CTRECOMB};
 pub use cubic::{cubic, CubicCon};