import subprocess

import os

import shutil

from pathlib import Path

from datetime import datetime, timedelta

import typing as T

try:

import psutil

except ImportError:

psutil = None

# pip install psutil will improve CPU utilization.

git = shutil.which("git")

Pathlike = T.Union[str, Path]

__all__ = ["gitrev", "get_cpu_count", "ymdhourdec2datetime", "datetime2ymd_hourdec"]

def gitrev() -> str:

if not git:

return ""

return subprocess.check_output([git, "rev-parse", "--short", "HEAD"], universal_newlines=True).strip()

def get_cpu_count() -> int:

""" get a physical CPU count

Returns

-------

count: int

detect number of physical CPU

"""

max_cpu = None

# without psutil, hyperthreaded CPU may overestimate physical count by factor of 2 (or more)

if psutil is not None:

max_cpu = psutil.cpu_count(logical=False)

extradiv = 1

if max_cpu is None:

max_cpu = psutil.cpu_count()

extradiv = 2

if max_cpu is None:

max_cpu = os.cpu_count()

extradiv = 2

return max_cpu // extradiv

def ymdhourdec2datetime(year: int, month: int, day: int, hourdec: float) -> datetime:

"""

convert year,month,day + decimal hour HH.hhh to time

"""

return datetime(year, month, day, int(hourdec), int((hourdec * 60) % 60)) + timedelta(seconds=(hourdec * 3600) % 60)

def datetime2ymd_hourdec(dt: datetime) -> str:

"""

convert datetime to ymd_hourdec string for filename stem

"""

return dt.strftime("%Y%m%d") + f"_{dt.hour*3600 + dt.minute*60 + dt.second + dt.microsecond/1e6:12.6f}"