examples/Basic/gui_estimator.py

"""
This example demonstrates how to make a graphical interface, and uses
a random number generator to simulate data so that it does not require
an instrument to use.

Run the program by changing to the directory containing this file and calling:

python gui.py

"""

import sys
import random
import tempfile
from time import sleep

from datetime import datetime, timedelta

from pymeasure.experiment import Procedure, IntegerParameter, Parameter, FloatParameter
from pymeasure.experiment import Results
from pymeasure.display.Qt import QtGui
from pymeasure.display.windows import ManagedWindow

import logging
log = logging.getLogger('')
log.addHandler(logging.NullHandler())


class TestProcedure(Procedure):

    iterations = IntegerParameter('Loop Iterations', default=100)
    delay = FloatParameter('Delay Time', units='s', default=0.2)
    seed = Parameter('Random Seed', default='12345')

    DATA_COLUMNS = ['Iteration', 'Random Number']

    def startup(self):
        log.info("Setting up random number generator")
        random.seed(self.seed)

    def execute(self):
        log.info("Starting to generate numbers")
        for i in range(self.iterations):
            data = {
                'Iteration': i,
                'Random Number': random.random()
            }
            log.debug("Produced numbers: %s" % data)
            self.emit('results', data)
            self.emit('progress', 100 * i / self.iterations)
            sleep(self.delay)
            if self.should_stop():
                log.warning("Catch stop command in procedure")
                break

    def get_estimates(self, sequence_length=None, sequence=None):
        """ Function that returns estimates for the EstimatorWidget. If this function
        is implemented (and does not return a NotImplementedError) the widget is
        automatically activated.

        The function is expected to return an int or float, or a list of tuples. If an int or
        float is returned, it should represent the duration in seconds.If a list of
        tuples is returned, each tuple containing two strings, a label and the estimate
        itself:
        estimates = [
            ("label 1", "estimate 1"),
            ("label 2", "estimate 2"),
        ]
        The length of the number of estimates is not limited but has to remain unchanged after
        initialisation. Note that also the label can be altered after initialisation.

        The keyword arguments `sequence_length` and `sequence` are optional and return
        (if asked for) the length of the current sequence (of the `SequencerWidget`) or
        the full sequence.

        """
        duration = self.iterations * self.delay

        """
        A simple implementation of the get_estimates function immediately returns the duration
        in seconds.
        """
        # return duration

        estimates = list()

        estimates.append(("Duration", "%d s" % int(duration)))
        estimates.append(("Number of lines", "%d" % int(self.iterations)))

        estimates.append(("Sequence length", str(sequence_length)))

        estimates.append(('Measurement finished at', str(datetime.now() + timedelta(
            seconds=duration))[:-7]))
        estimates.append(('Sequence finished at', str(datetime.now() + timedelta(
            seconds=duration * sequence_length))[:-7]))

        return estimates

    def shutdown(self):
        log.info("Finished")


class MainWindow(ManagedWindow):

    def __init__(self):
        super().__init__(
            procedure_class=TestProcedure,
            inputs=['iterations', 'delay', 'seed'],
            displays=['iterations', 'delay', 'seed'],
            x_axis='Iteration',
            y_axis='Random Number',
            sequencer=True,
            sequence_file="gui_sequencer_example_sequence.txt"
        )
        self.setWindowTitle('GUI Example')

    def queue(self, procedure=None):
        filename = tempfile.mktemp()

        if procedure is None:
            procedure = self.make_procedure()

        results = Results(procedure, filename)
        experiment = self.new_experiment(results)

        self.manager.queue(experiment)


if __name__ == "__main__":
    app = QtGui.QApplication(sys.argv)
    window = MainWindow()
    window.show()
    sys.exit(app.exec_())