# Example of summing all the values in a data stream
import rx
from rx import operators as op
# Set up a source
observable = rx.from_list([2, 3, 5, 7])
# Apply sum function to initial source
observable2 = observable.pipe(op.sum())
# Subscribe to the result generated by sum
observable2.subscribe(lambda v: print(v))
print('-' * 20)
# Rolling or incremental sum
rx.from_([2, 3, 5, 7]).pipe(
op.scan(lambda subtotal, i: subtotal + i)).subscribe(lambda v: print(v))
# By considering the terms in the Fibonacci sequence whose values do not
# exceed four million, find the sum of the even-valued terms.
MAX_VALUE = 4e6
# Legacy method
def fill_fibonacci(max_value):
fib_list = [1, 1]
increment = 1
while (True):
fib_list.append(fib_list[increment - 1] + fib_list[increment])
increment = increment + 1
if (fib_list[increment] > max_value):
fib_list.pop()
break
return fib_list
print(sum([num for num in fill_fibonacci(MAX_VALUE) if num % 2 == 0]))
# With reactive programming
from rx import from_list, operators as op
source = from_list(fill_fibonacci(MAX_VALUE))
source.pipe(op.filter(lambda x: x % 2 == 0),
op.sum()).subscribe(lambda i: print(i))
# A subscribers example
import rx
from rx.subjects import Subject
from datetime import datetime
# You can choose which of these to use
# source = rx.from_([2, 3, 5, 7])
# source = rx.from_iterable([2, 3, 5, 7])
source = rx.from_list([2, 3, 5, 7])
class TimeStampSubject(Subject):
""" Class implementing a Subject """
def on_next(self, value):
print('Subject Received', value)
super().on_next((value, datetime.now()))
def on_completed(self):
print('Data Stream Completed')
super().on_completed()
def on_error(self, error):
print('In Subject - Error Occurred', error)
super().on_error(error)
def prime_number_reporter(value):
print('Function Received', value)
def get_devices(self) -> Observable:
return rx.concat(rx.from_list(self.__device_list),
self.__added_devices)
def get_buses(self) -> Observable:
return rx.concat(rx.from_list(self.__bus_map.values()),
self.__bus_subject)
def _path_elements(path):
return from_list(path.split('/')).pipe(
filter(lambda name: name and name.strip()
) # Allow for double // and trailing / in path
)
def get_values(self) -> Observable:
return rx.concat(rx.from_list(self.__latest_values.values()),
self.__value_subject)
# An example illustrating how to merge two data sources
import rx
# Set up two sources
source1 = rx.from_list([2, 3, 5, 7])
source2 = rx.from_list([10, 11, 12])
# Use the merge function to create a single observable data stream
rx.merge(source1, source2)\
.subscribe(lambda v: print(v, end=','))
import rx
import rx.operators as op
import threading
# 与えられたものをそのまま
rx.just(3).subscribe(print)
rx.from_list([1, 2, 3, 4]).subscribe(print)
rx.from_iterable([1, 2, 3, 4]).subscribe(print)
# bufferはたまってから処理する
rx.from_iterable(range(10)).pipe(op.map(lambda x: x * 2),
op.buffer_with_count(3)).subscribe(print)
rx.from_iterable(range(10)).pipe(
op.map(lambda x: x * 2),
op.buffer_with_count(3),
# ここではリストになっている
op.map(len)).subscribe(print)
# windowもたまってから処理するがlistではなくObservableになる
rx.from_iterable(range(10)).pipe(
op.map(lambda x: x * 2),
op.window_with_count(3),
).subscribe(print)
# observableの中身を1つ1つ処理したい場合はflatmapが使える
rx.from_iterable(range(10)).pipe(
op.map(lambda x: x * 2),
op.window_with_count(3),
# ただしこの時点でxはObservable
# 複数のObservableを1つにまとめる
def vaciarFrameReactiveX(self, frame):
self.fuente = rx.from_list(frame.winfo_children()).pipe(
op.map(self.VaciarFrame))
frame.pack_forget()