Generator function for even numbers

[mp3909]

I am trying to write a generator function to output even numbers

Here is my code:

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def evenNumber(i):     r = i * 2     yield r     for i in range(1,21):     print(evenNumber(i))

However, this is what I get which is not what I want.

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<generator object evenNumber at 0x00F7BDB0> <generator object evenNumber at 0x00F7BDB0> <generator object evenNumber at 0x00F7BDB0> <generator object evenNumber at 0x00F7BDB0> <generator object evenNumber at 0x00F7BDB0> <generator object evenNumber at 0x00F7BDB0> <generator object evenNumber at 0x00F7BDB0> <generator object evenNumber at 0x00F7BDB0> <generator object evenNumber at 0x00F7BDB0> <generator object evenNumber at 0x00F7BDB0> <generator object evenNumber at 0x00F7BDB0> <generator object evenNumber at 0x00F7BDB0> <generator object evenNumber at 0x00F7BDB0> <generator object evenNumber at 0x00F7BDB0> <generator object evenNumber at 0x00F7BDB0> <generator object evenNumber at 0x00F7BDB0> <generator object evenNumber at 0x00F7BDB0> <generator object evenNumber at 0x00F7BDB0> <generator object evenNumber at 0x00F7BDB0> <generator object evenNumber at 0x00F7BDB0> [Finished in 0.145s]

[ndc85430]

You need to iterate over the generator, r.g. in a for loop or list comprehension, so that the calculation is run.

[DeaD_EyE]

The generator should written like this example:

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def number_gen(start=0, step=1):     while True:         yield start         start += step

It's an infinite generator, which means it has no exit condition.
Consuming this generator, requires for islice from itertools.

Consuming:

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from itertools import islice     for number in islice(number_gen(start=0, step=2), 0, 10):     print(number)

The number_gen code is not required, because it's in itertools.count.
Also the range object is very powerful and could solve your task if you need finite sequences.

1 2	even_numbers = list(range(0, 257, 2)) print(even_numbers)

[mp3909]

ok thanks.
this is now working.

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def evenNumber(s):     b = 1     while b <= s:         yield b*2         b += 1   for i in evenNumber(20):     print(i)

[buran]

it's better as

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def even_numbers(end):     for num in range(1, end + 1):         yield numb * 2

you can pass optional argument for start too