sst (1)

Example Python program sst (1).py Python version 3.x or newer. To check the Python version use:

python --version

Modules

• import attr
• import PyQt5.QtCore
• import sys
• import time

Classes

• class Timer:
• class O(PyQt5.QtCore.QObject):
• class PythonO:

Methods

• def start(self):
• def stop(self):
• def dt(self):
• def dts(self):
• def attrs_post_init(self):
• def slot(self):
• def method(self):
• def method(self):
• def main():

Code

Example Python PyQt program :

import attr
import PyQt5.QtCore
import sys
import time


@attr.s
class Timer:
    _start_time = attr.ib(default=None)
    _stop_time = attr.ib(default=None)
    format = '{: 3.6f}'

    def start(self):
        self._stop_time = None
        self._start_time = time.monotonic()

    def stop(self):
        self._stop_time = time.monotonic()

    def dt(self):
        return self._stop_time - self._start_time

    def dts(self):
        return self.format.format(self.dt())


@attr.s
class O(PyQt5.QtCore.QObject):
    signal = PyQt5.QtCore.pyqtSignal()
    timer = attr.ib()
    _parent = attr.ib() #don't want as a actually property...

    def __attrs_post_init__(self):
        super().__init__(self._parent)

    @PyQt5.QtCore.pyqtSlot()
    def slot(self):
        self.timer.stop()

    def method(self):
        self.timer.stop()


@attr.s
class PythonO:
    timer = attr.ib()

    def method(self):
        self.timer.stop()


def main():
    app = PyQt5.QtCore.QCoreApplication(sys.argv)

    timer = Timer()

    auto_signal = O(timer=timer, parent=app)
    queued_signal = O(timer=timer, parent=app)
    method_signal = O(timer=timer, parent=app)
    slot = O(timer=timer, parent=app)

    python_method_signal = O(timer=timer, parent=app)
    python_method_slot = PythonO(timer=timer)

    auto_signal.signal.connect(slot.slot)
    queued_signal.signal.connect(slot.slot, PyQt5.QtCore.Qt.QueuedConnection)
    method_signal.signal.connect(slot.method)
    python_method_signal.signal.connect(python_method_slot.method)

    n = 1000000

    multiple_dt = 0
    for _ in range(n):
        timer.start()
        slot.slot()
        multiple_dt += timer.dt()

    print('{:>30s}'.format('direct: ') + timer.format.format(multiple_dt))


    multiple_dt = 0
    for _ in range(n):
        timer.start()
        auto_signal.signal.emit()

        multiple_dt += timer.dt()

    print('{:>30s}'.format('signal/slot: ') + timer.format.format(multiple_dt))

    multiple_dt = 0
    for _ in range(n):
        timer.start()
        queued_signal.signal.emit()
        app.processEvents()

        multiple_dt += timer.dt()

    print('{:>30s}'.format('queued signal/slot: ') + timer.format.format(multiple_dt))

    multiple_dt = 0
    for _ in range(n):
        timer.start()
        method_signal.signal.emit()

        multiple_dt += timer.dt()

    print(
        '{:>30s}'.format('method signal/slot: ') + timer.format.format(multiple_dt))

    multiple_dt = 0
    for _ in range(n):
        timer.start()
        python_method_signal.signal.emit()

        multiple_dt += timer.dt()

    print(
        '{:>30s}'.format('python method signal/slot: ') + timer.format.format(
            multiple_dt))


if __name__ == '__main__':
    sys.exit(main())

Useful Links

• Articles: https://python-commandments.org/
• PyQt: https://pythonpyqt.com/
• Tutorial: https://pythonprogramminglanguage.com/