robustdg/algorithms/irm.py

138 строки
6.1 KiB
Python

import sys
import numpy as np
import argparse
import copy
import random
import json
import torch
from torch.autograd import grad
from torch import nn, optim
from torch.nn import functional as F
from torchvision import datasets, transforms
from torchvision.utils import save_image
from torch.autograd import Variable
import torch.utils.data as data_utils
from .algo import BaseAlgo
from utils.helper import l1_dist, l2_dist, embedding_dist, cosine_similarity, compute_irm_penalty
class Irm(BaseAlgo):
def __init__(self, args, train_dataset, val_dataset, test_dataset, base_res_dir, post_string, cuda):
super().__init__(args, train_dataset, val_dataset, test_dataset, base_res_dir, post_string, cuda)
def train(self):
self.max_epoch=-1
self.max_val_acc=0.0
for epoch in range(self.args.epochs):
if epoch ==0 or (epoch % self.args.match_interrupt == 0 and self.args.match_flag):
data_match_tensor, label_match_tensor= self.get_match_function(epoch)
penalty_erm=0
penalty_irm=0
train_acc= 0.0
train_size=0
perm = torch.randperm(data_match_tensor.size(0))
data_match_tensor_split= torch.split(data_match_tensor[perm], self.args.batch_size, dim=0)
label_match_tensor_split= torch.split(label_match_tensor[perm], self.args.batch_size, dim=0)
print('Split Matched Data: ', len(data_match_tensor_split), data_match_tensor_split[0].shape, len(label_match_tensor_split))
#Batch iteration over single epoch
for batch_idx, (x_e, y_e ,d_e, idx_e) in enumerate(self.train_dataset):
# print('Batch Idx: ', batch_idx)
self.opt.zero_grad()
loss_e= torch.tensor(0.0).to(self.cuda)
x_e= x_e.to(self.cuda)
y_e= torch.argmax(y_e, dim=1).to(self.cuda)
d_e= torch.argmax(d_e, dim=1).numpy()
#Forward Pass
out= self.phi(x_e)
irm_loss=torch.tensor(0.0).to(self.cuda)
erm_loss= torch.tensor(0.0).to(self.cuda)
# To cover the varying size of the last batch for data_match_tensor_split, label_match_tensor_split
total_batch_size= len(data_match_tensor_split)
if batch_idx >= total_batch_size:
break
curr_batch_size= data_match_tensor_split[batch_idx].shape[0]
data_match= data_match_tensor_split[batch_idx].to(self.cuda)
data_match= data_match.view( data_match.shape[0]*data_match.shape[1], data_match.shape[2], data_match.shape[3], data_match.shape[4] )
feat_match= self.phi( data_match )
label_match= label_match_tensor_split[batch_idx].to(self.cuda)
label_match= label_match.view( label_match.shape[0]*label_match.shape[1] )
erm_loss+= F.cross_entropy(feat_match, label_match.long()).to(self.cuda)
penalty_erm+= float(erm_loss)
loss_e += erm_loss
train_acc+= torch.sum(torch.argmax(feat_match, dim=1) == label_match ).item()
train_size+= label_match.shape[0]
# Creating tensor of shape ( domain size, total domains, feat size )
if len(feat_match.shape) == 4:
feat_match= feat_match.view( curr_batch_size, len(self.train_domains), feat_match.shape[1]*feat_match.shape[2]*feat_match.shape[3] )
else:
feat_match= feat_match.view( curr_batch_size, len(self.train_domains), feat_match.shape[1] )
label_match= label_match.view( curr_batch_size, len(self.train_domains) )
# print(feat_match.shape)
data_match= data_match.view( curr_batch_size, len(self.train_domains), data_match.shape[1], data_match.shape[2], data_match.shape[3] )
#IRM Penalty
domain_counter=0
for d_i in range(feat_match.shape[1]):
irm_loss+= compute_irm_penalty( feat_match[:, d_i, :], label_match[:, d_i], self.cuda )
domain_counter+=1
irm_loss = irm_loss/domain_counter
penalty_irm+= float(irm_loss)
#IRM Penalty to be minimized only after threshold epoch
if epoch > self.args.penalty_s:
loss_e += self.args.penalty_irm*irm_loss
if self.args.penalty_irm > 1.0:
# Rescale the entire loss to keep gradients in a reasonable range
loss_e /= self.args.penalty_irm
loss_e.backward(retain_graph=False)
self.opt.step()
del erm_loss
del irm_loss
del loss_e
torch.cuda.empty_cache()
print('Train Loss Basic : ', penalty_erm, penalty_irm )
print('Train Acc Env : ', 100*train_acc/train_size )
print('Done Training for epoch: ', epoch)
#Train Dataset Accuracy
self.train_acc.append( 100*train_acc/train_size )
#Val Dataset Accuracy
self.val_acc.append( self.get_test_accuracy('val') )
#Test Dataset Accuracy
self.final_acc.append( self.get_test_accuracy('test') )
#Save the model if current best epoch as per validation loss
if self.val_acc[-1] > self.max_val_acc:
self.max_val_acc=self.val_acc[-1]
self.max_epoch= epoch
self.save_model()
print('Current Best Epoch: ', self.max_epoch, ' with Test Accuracy: ', self.final_acc[self.max_epoch])