Merge pull request #13 from vaaaaanquish/save_file

Save file/Load file

Author: vaaaaanquish

.github/workflows/test.yml

@@ -32,6 +32,7 @@ jobs:
     - name: Build for ubuntu
       if: matrix.os == 'ubuntu-latest'
       run: |
+          sudo apt-get update
           sudo apt-get install -y cmake libclang-dev libc++-dev gcc-multilib
           cargo build
     - name: Run tests

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "lightgbm"
-version = "0.1.2"
+version = "0.1.3"
 authors = ["vaaaaanquish <[email protected]>"]
 license = "MIT"
 repository = "https://github.com/vaaaaanquish/LightGBM"

src/booster.rs

@@ -13,13 +13,27 @@ use super::{LGBMResult, Dataset, LGBMError};
 /// Core model in LightGBM, containing functions for training, evaluating and predicting.
 pub struct Booster {
     pub(super) handle: lightgbm_sys::BoosterHandle,
-    num_class: i64
 }
 
 
 impl Booster {
-    fn new(handle: lightgbm_sys::BoosterHandle, num_class: i64) -> LGBMResult<Self> {
-        Ok(Booster{handle, num_class})
+    fn new(handle: lightgbm_sys::BoosterHandle) -> LGBMResult<Self> {
+        Ok(Booster{handle})
+    }
+
+    /// Init from model file.
+    pub fn from_file(filename: String) -> LGBMResult<Self>{
+        let filename_str = CString::new(filename).unwrap();
+        let mut out_num_iterations = 0;
+        let mut handle = std::ptr::null_mut();
+        lgbm_call!(
+            lightgbm_sys::LGBM_BoosterCreateFromModelfile(
+                filename_str.as_ptr() as *const c_char,
+                &mut out_num_iterations,
+                &mut handle
+            )
+        ).unwrap();
+        Ok(Booster::new(handle)?)
     }
 
     /// Create a new Booster model with given Dataset and parameters.
@@ -56,14 +70,6 @@ impl Booster {
             num_iterations = parameter["num_iterations"].as_i64().unwrap();
         }
 
-        // get num_class
-        let num_class: i64;
-        if parameter["num_class"].is_null(){
-            num_class = 1;
-        } else {
-            num_class = parameter["num_class"].as_i64().unwrap();
-        }
-
         // exchange params {"x": "y", "z": 1} => "x=y z=1"
         let params_string = parameter.as_object().unwrap().iter().map(|(k, v)| format!("{}={}", k, v)).collect::<Vec<_>>().join(" ");
         let params_cstring = CString::new(params_string).unwrap();
@@ -81,7 +87,7 @@ impl Booster {
         for _ in 1..num_iterations {
             lgbm_call!(lightgbm_sys::LGBM_BoosterUpdateOneIter(handle, &mut is_finished))?;
         }
-        Ok(Booster::new(handle, num_class)?)
+        Ok(Booster::new(handle)?)
     }
 
     /// Predict results for given data.
@@ -102,9 +108,19 @@ impl Booster {
         let feature_length = data[0].len();
         let params = CString::new("").unwrap();
         let mut out_length: c_long = 0;
-        let out_result: Vec<f64> = vec![Default::default(); data.len() * self.num_class as usize];
         let flat_data = data.into_iter().flatten().collect::<Vec<_>>();
 
+        // get num_class
+        let mut num_class = 0;
+        lgbm_call!(
+            lightgbm_sys::LGBM_BoosterGetNumClasses(
+                self.handle,
+                &mut num_class
+            )
+        )?;
+
+        let out_result: Vec<f64> = vec![Default::default(); data_length * num_class as usize];
+
         lgbm_call!(
             lightgbm_sys::LGBM_BoosterPredictForMat(
                 self.handle,
@@ -124,13 +140,28 @@ impl Booster {
 
         // reshape for multiclass [1,2,3,4,5,6] -> [[1,2,3], [4,5,6]]  # 3 class
         let reshaped_output;
-        if self.num_class > 1{
-            reshaped_output = out_result.chunks(self.num_class as usize).map(|x| x.to_vec()).collect();
+        if num_class > 1{
+            reshaped_output = out_result.chunks(num_class as usize).map(|x| x.to_vec()).collect();
         } else {
             reshaped_output = vec![out_result];
         }
         Ok(reshaped_output)
     }
+
+
+    /// Save model to file.
+    pub fn save_file(&self, filename: String){
+        let filename_str = CString::new(filename).unwrap();
+        lgbm_call!(
+            lightgbm_sys::LGBM_BoosterSaveModel(
+                self.handle,
+                0 as i32,
+                -1 as i32,
+                0 as i32,
+                filename_str.as_ptr() as *const c_char
+            )
+        ).unwrap();
+    }
 }
 
 
@@ -145,6 +176,9 @@ impl Drop for Booster {
 mod tests {
     use super::*;
     use serde_json::json;
+    use std::path::Path;
+    use std::fs;
+
     fn read_train_file() -> LGBMResult<Dataset> {
         Dataset::from_file("lightgbm-sys/lightgbm/examples/binary_classification/binary.train".to_string())
     }
@@ -173,4 +207,26 @@ mod tests {
         }
         assert_eq!(normalized_result, vec![0, 0, 1]);
     }
+
+    #[test]
+    fn save_file() {
+        let dataset = read_train_file().unwrap();
+        let params = json!{
+            {
+                "num_iterations": 1,
+                "objective": "binary",
+                "metric": "auc",
+                "data_random_seed": 0
+            }
+        };
+        let bst = Booster::train(dataset, &params).unwrap();
+        bst.save_file("./test/test_save_file.output".to_string());
+        assert!(Path::new("./test/test_save_file.output").exists());
+        fs::remove_file("./test/test_save_file.output");
+    }
+
+    #[test]
+    fn from_file(){
+        let bst = Booster::from_file("./test/test_from_file.input".to_string());
+    }
 }

test/test_from_file.input

@@ -0,0 +1,127 @@
+tree
+version=v3
+num_class=1
+num_tree_per_iteration=1
+label_index=0
+max_feature_idx=27
+objective=binary sigmoid:1
+feature_names=Column_0 Column_1 Column_2 Column_3 Column_4 Column_5 Column_6 Column_7 Column_8 Column_9 Column_10 Column_11 Column_12 Column_13 Column_14 Column_15 Column_16 Column_17 Column_18 Column_19 Column_20 Column_21 Column_22 Column_23 Column_24 Column_25 Column_26 Column_27
+feature_infos=[0.27500000000000002:6.6950000000000003] [-2.4169999999999998:2.4300000000000002] [-1.7429999999999999:1.7429999999999999] [0.019:5.7000000000000002] [-1.7429999999999999:1.7429999999999999] [0.159:4.1900000000000004] [-2.9409999999999998:2.9699999999999998] [-1.7410000000000001:1.7410000000000001] [0:2.173] [0.19:5.1929999999999996] [-2.9039999999999999:2.9089999999999998] [-1.742:1.7429999999999999] [0:2.2149999999999999] [0.26400000000000001:6.5229999999999997] [-2.7279999999999998:2.7269999999999999] [-1.742:1.742] [0:2.548] [0.36499999999999999:6.0679999999999996] [-2.4950000000000001:2.496] [-1.74:1.7429999999999999] [0:3.1019999999999999] [0.17199999999999999:13.098000000000001] [0.41899999999999998:7.3920000000000003] [0.46100000000000002:3.6819999999999999] [0.38400000000000001:6.5830000000000002] [0.092999999999999999:7.8600000000000003] [0.38900000000000001:4.5430000000000001] [0.48899999999999999:4.3159999999999998]
+tree_sizes=
+
+end of trees
+
+feature_importances:
+
+parameters:
+[boosting: gbdt]
+[objective: binary]
+[metric: auc]
+[tree_learner: serial]
+[device_type: cpu]
+[linear_tree: 0]
+[data: ]
+[valid: ]
+[num_iterations: 1]
+[learning_rate: 0.1]
+[num_leaves: 31]
+[num_threads: 0]
+[deterministic: 0]
+[force_col_wise: 0]
+[force_row_wise: 0]
+[histogram_pool_size: -1]
+[max_depth: -1]
+[min_data_in_leaf: 20]
+[min_sum_hessian_in_leaf: 0.001]
+[bagging_fraction: 1]
+[pos_bagging_fraction: 1]
+[neg_bagging_fraction: 1]
+[bagging_freq: 0]
+[bagging_seed: 3]
+[feature_fraction: 1]
+[feature_fraction_bynode: 1]
+[feature_fraction_seed: 2]
+[extra_trees: 0]
+[extra_seed: 6]
+[early_stopping_round: 0]
+[first_metric_only: 0]
+[max_delta_step: 0]
+[lambda_l1: 0]
+[lambda_l2: 0]
+[linear_lambda: 0]
+[min_gain_to_split: 0]
+[drop_rate: 0.1]
+[max_drop: 50]
+[skip_drop: 0.5]
+[xgboost_dart_mode: 0]
+[uniform_drop: 0]
+[drop_seed: 4]
+[top_rate: 0.2]
+[other_rate: 0.1]
+[min_data_per_group: 100]
+[max_cat_threshold: 32]
+[cat_l2: 10]
+[cat_smooth: 10]
+[max_cat_to_onehot: 4]
+[top_k: 20]
+[monotone_constraints: ]
+[monotone_constraints_method: basic]
+[monotone_penalty: 0]
+[feature_contri: ]
+[forcedsplits_filename: ]
+[refit_decay_rate: 0.9]
+[cegb_tradeoff: 1]
+[cegb_penalty_split: 0]
+[cegb_penalty_feature_lazy: ]
+[cegb_penalty_feature_coupled: ]
+[path_smooth: 0]
+[interaction_constraints: ]
+[verbosity: 1]
+[saved_feature_importance_type: 0]
+[max_bin: 255]
+[max_bin_by_feature: ]
+[min_data_in_bin: 3]
+[bin_construct_sample_cnt: 200000]
+[data_random_seed: 0]
+[is_enable_sparse: 1]
+[enable_bundle: 1]
+[use_missing: 1]
+[zero_as_missing: 0]
+[feature_pre_filter: 1]
+[pre_partition: 0]
+[two_round: 0]
+[header: 0]
+[label_column: ]
+[weight_column: ]
+[group_column: ]
+[ignore_column: ]
+[categorical_feature: ]
+[forcedbins_filename: ]
+[objective_seed: 5]
+[num_class: 1]
+[is_unbalance: 0]
+[scale_pos_weight: 1]
+[sigmoid: 1]
+[boost_from_average: 1]
+[reg_sqrt: 0]
+[alpha: 0.9]
+[fair_c: 1]
+[poisson_max_delta_step: 0.7]
+[tweedie_variance_power: 1.5]
+[lambdarank_truncation_level: 30]
+[lambdarank_norm: 1]
+[label_gain: ]
+[eval_at: ]
+[multi_error_top_k: 1]
+[auc_mu_weights: ]
+[num_machines: 1]
+[local_listen_port: 12400]
+[time_out: 120]
+[machine_list_filename: ]
+[machines: ]
+[gpu_platform_id: -1]
+[gpu_device_id: -1]
+[gpu_use_dp: 0]
+[num_gpu: 1]
+
+end of parameters