Source code for mhcflurry.train_processing_models_command

"""
Train Class1 processing models.
"""
from __future__ import print_function
import argparse
import os
from os.path import join
import signal
import sys
import time
import traceback
import random
import pprint
import hashlib
import pickle
import uuid
from functools import partial

import numpy
import pandas
import yaml
import tqdm  # progress bar
tqdm.monitor_interval = 0  # see https://github.com/tqdm/tqdm/issues/481

from .class1_processing_predictor import Class1ProcessingPredictor
from .class1_processing_neural_network import Class1ProcessingNeuralNetwork
from .common import configure_logging
from .local_parallelism import (
    add_local_parallelism_args,
    worker_pool_with_gpu_assignments_from_args,
    call_wrapped_kwargs)
from .cluster_parallelism import (
    add_cluster_parallelism_args,
    cluster_results_from_args)

# To avoid pickling large matrices to send to child processes when running in
# parallel, we use this global variable as a place to store data. Data that is
# stored here before creating the thread pool will be inherited to the child
# processes upon fork() call, allowing us to share large data with the workers
# via shared memory.
GLOBAL_DATA = {}

# Note on parallelization:
# It seems essential currently (tensorflow==1.4.1) that no processes are forked
# after tensorflow has been used at all, which includes merely importing
# keras.backend. So we must make sure not to use tensorflow in the main process
# if we are running in parallel.

parser = argparse.ArgumentParser(usage=__doc__)

parser.add_argument(
    "--data",
    metavar="FILE.csv",
    help="Training data CSV. Expected columns: peptide, n_flank, c_flank, hit")
parser.add_argument(
    "--out-models-dir",
    metavar="DIR",
    required=True,
    help="Directory to write models and manifest")
parser.add_argument(
    "--hyperparameters",
    metavar="FILE.json",
    help="JSON or YAML of hyperparameters")
parser.add_argument(
    "--held-out-samples",
    type=int,
    metavar="N",
    default=10,
    help="Number of experiments to hold out per fold")
parser.add_argument(
    "--num-folds",
    type=int,
    default=4,
    metavar="N",
    help="Number of training folds.")
parser.add_argument(
    "--num-replicates",
    type=int,
    metavar="N",
    default=1,
    help="Number of replicates per (architecture, fold) pair to train.")
parser.add_argument(
    "--max-epochs",
    type=int,
    metavar="N",
    help="Max training epochs. If specified here it overrides any 'max_epochs' "
    "specified in the hyperparameters.")
parser.add_argument(
    "--verbosity",
    type=int,
    help="Keras verbosity. Default: %(default)s",
    default=0)
parser.add_argument(
    "--debug",
    action="store_true",
    default=False,
    help="Launch python debugger on error")
parser.add_argument(
    "--continue-incomplete",
    action="store_true",
    default=False,
    help="Continue training models from an incomplete training run. If this is "
    "specified then the only required argument is --out-models-dir")
parser.add_argument(
    "--only-initialize",
    action="store_true",
    default=False,
    help="Do not actually train models. The initialized run can be continued "
    "later with --continue-incomplete.")

add_local_parallelism_args(parser)
add_cluster_parallelism_args(parser)


[docs]def assign_folds(df, num_folds, held_out_samples): """ Split training data into mulitple test/train pairs, which we refer to as folds. Note that a given data point may be assigned to multiple test or train sets; these folds are NOT a non-overlapping partition as used in cross validation. A fold is defined by a boolean value for each data point, indicating whether it is included in the training data for that fold. If it's not in the training data, then it's in the test data. Parameters ---------- df : pandas.DataFrame training data num_folds : int held_out_samples : int Returns ------- pandas.DataFrame index is same as df.index, columns are "fold_0", ... "fold_N" giving whether the data point is in the training data for the fold """ result_df = pandas.DataFrame(index=df.index) sample_names = pandas.Series(df.sample_id.unique()) for fold in range(num_folds): samples_to_exclude = sample_names.sample(n=held_out_samples) result_df["fold_%d" % fold] = ~df.sample_id.isin(samples_to_exclude) print("Fold", fold, "holding out samples", *samples_to_exclude) print("Training points per fold") print(result_df.sum()) print("Test points per fold") print((~result_df).sum()) return result_df
[docs]def run(argv=sys.argv[1:]): # On sigusr1 print stack trace print("To show stack trace, run:\nkill -s USR1 %d" % os.getpid()) signal.signal(signal.SIGUSR1, lambda sig, frame: traceback.print_stack()) args = parser.parse_args(argv) if args.debug: try: return main(args) except Exception as e: print(e) import ipdb # pylint: disable=import-error ipdb.set_trace() raise else: return main(args)
[docs]def main(args): print("Arguments:") print(args) args.out_models_dir = os.path.abspath(args.out_models_dir) configure_logging(verbose=args.verbosity > 1) if not args.continue_incomplete: initialize_training(args) if not args.only_initialize: train_models(args)
[docs]def initialize_training(args): required_arguments = [ "data", "out_models_dir", "hyperparameters", "num_folds", ] for arg in required_arguments: if getattr(args, arg) is None: parser.error("Missing required arg: %s" % arg) print("Initializing training.") hyperparameters_lst = yaml.load(open(args.hyperparameters)) assert isinstance(hyperparameters_lst, list) print("Loaded hyperparameters list:") if len(hyperparameters_lst) > 7: pprint.pprint(hyperparameters_lst[:3]) print("...") pprint.pprint(hyperparameters_lst[-3:]) else: pprint.pprint(hyperparameters_lst) print("Length of hyperparameters list: %d" % (len(hyperparameters_lst))) df = pandas.read_csv(args.data) print("Loaded training data: %s" % (str(df.shape))) df = df.loc[ (df.peptide.str.len() >= 8) & (df.peptide.str.len() <= 15) ] print("Subselected to 8-15mers: %s" % (str(df.shape))) folds_df = assign_folds( df=df, num_folds=args.num_folds, held_out_samples=args.held_out_samples) if not os.path.exists(args.out_models_dir): print("Attempting to create directory: %s" % args.out_models_dir) os.mkdir(args.out_models_dir) print("Done.") predictor = Class1ProcessingPredictor( models=[], metadata_dataframes={ 'train_data': pandas.merge( df, folds_df, left_index=True, right_index=True) }) work_items = [] for (h, hyperparameters) in enumerate(hyperparameters_lst): if args.max_epochs: hyperparameters['max_epochs'] = args.max_epochs for fold in range(args.num_folds): for replicate in range(args.num_replicates): work_dict = { 'work_item_name': str(uuid.uuid4()), 'architecture_num': h, 'num_architectures': len(hyperparameters_lst), 'fold_num': fold, 'num_folds': args.num_folds, 'replicate_num': replicate, 'num_replicates': args.num_replicates, 'hyperparameters': hyperparameters, } work_items.append(work_dict) training_init_info = {} training_init_info["train_data"] = df training_init_info["folds_df"] = folds_df training_init_info["work_items"] = work_items # Save empty predictor (for metadata) predictor.save(args.out_models_dir) # Write training_init_info. with open(join(args.out_models_dir, "training_init_info.pkl"), "wb") as fd: pickle.dump(training_init_info, fd, protocol=pickle.HIGHEST_PROTOCOL) print("Done initializing training.")
[docs]def train_models(args): global GLOBAL_DATA print("Beginning training.") predictor = Class1ProcessingPredictor.load(args.out_models_dir) print("Loaded predictor with %d networks" % len(predictor.models)) with open(join(args.out_models_dir, "training_init_info.pkl"), "rb") as fd: GLOBAL_DATA.update(pickle.load(fd)) print("Loaded training init info.") all_work_items = GLOBAL_DATA["work_items"] complete_work_item_names = [ network.fit_info[-1]["training_info"]["work_item_name"] for network in predictor.models ] work_items = [ item for item in all_work_items if item["work_item_name"] not in complete_work_item_names ] print("Found %d work items, of which %d are incomplete and will run now." % ( len(all_work_items), len(work_items))) serial_run = not args.cluster_parallelism and args.num_jobs == 0 # The estimated time to completion is more accurate if we randomize # the order of the work. random.shuffle(work_items) for (work_item_num, item) in enumerate(work_items): item['work_item_num'] = work_item_num item['num_work_items'] = len(work_items) item['progress_print_interval'] = 60.0 if not serial_run else 5.0 item['predictor'] = predictor if serial_run else None item['save_to'] = args.out_models_dir if serial_run else None item['verbose'] = args.verbosity start = time.time() worker_pool = None if serial_run: # Run in serial. Every worker is passed the same predictor, # which it adds models to, so no merging is required. It also saves # as it goes so no saving is required at the end. print("Processing %d work items in serial." % len(work_items)) for _ in tqdm.trange(len(work_items)): item = work_items.pop(0) # want to keep freeing up memory work_predictor = train_model(**item) assert work_predictor is predictor pprint.pprint(predictor.models[-1].fit_info[-1]['training_info']) assert not work_items results_generator = None elif args.cluster_parallelism: # Run using separate processes HPC cluster. results_generator = cluster_results_from_args( args, work_function=train_model, work_items=work_items, constant_data=GLOBAL_DATA, result_serialization_method="pickle") else: worker_pool = worker_pool_with_gpu_assignments_from_args(args) print("Worker pool", worker_pool) assert worker_pool is not None print("Processing %d work items in parallel." % len(work_items)) assert not serial_run for item in work_items: item['constant_data'] = GLOBAL_DATA results_generator = worker_pool.imap_unordered( partial(call_wrapped_kwargs, train_model), work_items, chunksize=1) if results_generator: for new_predictor in tqdm.tqdm(results_generator, total=len(work_items)): save_start = time.time() (model,) = new_predictor.models pprint.pprint(model.fit_info[-1]['training_info']) (new_model_name,) = predictor.add_models(new_predictor.models) predictor.save( args.out_models_dir, model_names_to_write=[new_model_name], write_metadata=False) print( "Saved predictor (%d models total) with 1 new models" "in %0.2f sec to %s" % ( len(predictor.models), time.time() - save_start, args.out_models_dir)) predictor.save(args.out_models_dir) print("Done saving.") print("*" * 30) training_time = time.time() - start print("Trained affinity predictor with %d networks in %0.2f min." % ( len(predictor.models), training_time / 60.0)) print("*" * 30) if worker_pool: worker_pool.close() worker_pool.join() print("Predictor written to: %s" % args.out_models_dir)
[docs]def train_model( work_item_name, work_item_num, num_work_items, architecture_num, num_architectures, fold_num, num_folds, replicate_num, num_replicates, hyperparameters, verbose, progress_print_interval, predictor, save_to, constant_data=GLOBAL_DATA): from sklearn.metrics import roc_auc_score from mhcflurry.flanking_encoding import FlankingEncoding df = constant_data["train_data"] folds_df = constant_data["folds_df"] if predictor is None: predictor = Class1ProcessingPredictor(models=[]) numpy.testing.assert_equal(len(df), len(folds_df)) train_data = df.loc[ folds_df["fold_%d" % fold_num] ].sample(frac=1.0).copy() test_data = df.loc[~folds_df["fold_%d" % fold_num]].copy() print("Training on %d points (%d points held-out)." % ( len(train_data), len(test_data))) progress_preamble = ( "[task %2d / %2d]: " "[%2d / %2d folds] " "[%2d / %2d architectures] " "[%4d / %4d replicates] " % ( work_item_num + 1, num_work_items, fold_num + 1, num_folds, architecture_num + 1, num_architectures, replicate_num + 1, num_replicates)) print("%s [pid %d]. Hyperparameters:" % (progress_preamble, os.getpid())) pprint.pprint(hyperparameters) model = Class1ProcessingNeuralNetwork(**hyperparameters) model.fit( sequences=FlankingEncoding( peptides=train_data.peptide.values, n_flanks=train_data.n_flank.values, c_flanks=train_data.c_flank.values), targets=train_data.hit.values, progress_preamble=progress_preamble, progress_print_interval=progress_print_interval, verbose=verbose) # Save model-specific training info train_peptide_hash = hashlib.sha1() for peptide in sorted(train_data.peptide.values): train_peptide_hash.update(peptide.encode()) # Compute AUC on held-out data just so it can be logged. for some_df in [train_data, test_data]: some_df["prediction"] = model.predict( peptides=some_df.peptide.values, n_flanks=some_df.n_flank.values, c_flanks=some_df.c_flank.values) train_auc = roc_auc_score( train_data.hit.values, train_data.prediction.values) test_auc = roc_auc_score(test_data.hit.values, test_data.prediction.values) print("Train AUC", train_auc) print("Test AUC", test_auc) model.fit_info[-1].setdefault("training_info", {}).update({ "fold_num": fold_num, "num_folds": num_folds, "replicate_num": replicate_num, "num_replicates": num_replicates, "architecture_num": architecture_num, "num_architectures": num_architectures, "train_peptide_hash": train_peptide_hash.hexdigest(), "work_item_name": work_item_name, "train_auc": train_auc, "test_auc": test_auc, }) numpy.testing.assert_equal( predictor.manifest_df.shape[0], len(predictor.models)) predictor.add_models([model]) if save_to: predictor.save(save_to) print("Wrote", save_to) numpy.testing.assert_equal( predictor.manifest_df.shape[0], len(predictor.models)) # Delete the network to release memory model._network = None # release tensorflow network return predictor
if __name__ == '__main__': run()