Скорее всего уже слышали, что складывать строки через + это плохая практика. Падение производительности, и всё такое. Без лишних слов, давайте измерять:
from timeit import timeit
def t1():
# складываем 10 строк через + из переменной
t = 'text'
for _ in range(1000):
s = t + t + t + t + t + t + t + t + t
def t2():
# склеиваем список строк через метод join
arr = ['text'] * 10
for _ in range(1000):
s = ''.join(arr)
def t3():
# складываем через + но не из переменной а непосредственно инлайн объекты
for _ in range(1000):
s = 'text' + 'text' + 'text' + ... # всего 10 раз
Теперь каждую строку склейки запустим по 10М раз
>>> timeit(t1, number=10000)
0.21951690399964718
>>> timeit(t2, number=10000)
1.4978306379998685
>>> timeit(t3, number=10000)
0.2213820789993406
Хм, а нам говорили что через "+" это плохо и медленно ))) 😁
Тут стоит учитывать, что речь идёт о склейке множества длинных строк.
Давайте изменим условия:
def t4():
t = 'text'*100
for _ in range(1000):
s = t + t + t + t + t + t + t + t + t
def t5():
arr = ['text'*100] * 10
for _ in range(1000):
s = ''.join(arr)
def t6():
for _ in range(1000):
s = 'text'*100 + 'text'*100 + ... # всего 10 раз
>>> timeit(t4, number=10000)
12.795130728000004
>>> timeit(t5, number=10000)
2.642637542999182
>>> timeit(t6, number=10000)
0.2184546610005782
Вот, уже другой разговор, сразу видна разница, в среднем в 6 раз. Но погодите, почему последний тест t6() по скорости такой же как и t3()? Ведь строки теперь в 100 раз длиннее!
Это вопросы оптимизации кода, какие простые изменения ускоряют или замедляют выполнение программы. Мы столкнулись с примером обхода обращения к переменной. Например, именно так работает директива #define в С++, во время компиляции подставляя значение переменной вместо ссылки на неё.
В Python это тоже работает, но часто ли вы сможете встретить такой способ работы со строками? К сожалению, способ почти только теоретический.
В целом, тесты показали то, что мы хотели. Делаем выводы самостоятельно.
Полный листинг 🌍
#tricks
Phrasal verbs with "sleep":
○sleep in
●sleep on
○sleep off
●sleep over
○sleep through
sleep in
Example: I usually sleep in on weekends.
sleep on (it)
Example: I’m not sure about this offer. Let me sleep on it.
sleep off
Example: After the marathon, he slept off his exhaustion.
sleep over
Example: My friend invited me to sleep over at her house.
sleep through
Example: I slept through the storm last night.
••┈┈●•❁❁✹❁❁•●┈┈┈••
#phrasalverbs
#Phrasalverbs
@fluencyinenglish
❇️show up
حضور یافتن در جایی
When you appear somewhere, you show up.
👉Turn up is similar to show up.
Turn up
مترادف show up میباشد
Example:
1. I was supposed to meet my sister for lunch, but she didn't show up.
@fluencyinenglish
2. Over a hundred people showed up for the news conference.
____________________________
show up
ظاهر شدن
When something appears or becomes visible, it shows up.
@fluencyinenglish
Example:
1. It's hard to photograph polar bears because they don't show up well against the snow.
2. The spots won't show up until the last stages of the disease.
@fluencyinenglish
❇️knuckle down
If you knuckle down, you start to take your work or your task seriously and do it properly.
❇️For example:
knuckle down
🔹The exams start next month, so I guess it's time I knuckled down and studied a bit harder.
knuckle down
🔹If Sammy wants to lose weight, he'll have to knuckle down and start exercising more at the gym
🔹knucklehead/n/
UK /ˈnʌk.əl.hed/
US/ˈnʌk.əl.hed/ us informal
A stupid person
@fluencyinenglish
💡Phrasal Verb
"Set out"
🧐Meaning
to explain the details of something, especially in writing
✅Example:
A contract should clearly set out the responsibilities of each party.
#PhrasalVerbs
💡Phrasal Verb
"take in (2)"
🧐Meaning
to fully understand something you hear or read
✅Example:
I had to read the article a second time to really take it all in. It wasn't easy to understand.
#phrasalverbs
💡Phrasal Verb
"grow on"
🧐Meaning
If something grows on you, you gradually start to like it, even though you didn't like it much at first.
✅Example:
I didn't like the music at first, but it's grown on me and I like it a lot now.
#phrasalverbs
#Teamjimmy
#sirjimmy
💡Phrasal Verb
"to get (something) across"
🧐Meaning:
to express (something) clearly so that it is understood:
✅Example:
I don't know if I was able to get my point across to you.
#Phrasalverbs
#Teamjimmy
#sirjimmy
#vocabulary
#phrasalverbs
#advanced_vocabulary
@fluencyinenglish
@fluencyinenglish
@fluencyinenglish
🔹amount to something
/əˈmɑʊnt·tə, -ˌtu/
to add up to, be in total, be equal to, or be the same as
Example: Federal and state costs for building and operating prisons amounted to $25 billion.
Example: The blog amounts to a critique of the U.S. news media.
@fluencyinenglish
@fluencyinenglish
@fluencyinenglish
✴️Cede: To give up control; surrender
(sēd)
Example - "The police officers had to cede control to the FBI agents."
@fluencyinenglish
@fluencyinenglish
@fluencyinenglish
✴️Promenade: Leisurely walk
(prŏm′ə-nād′, -näd′)
Example - "The couple promenaded around town with matching outfits on."
@fluencyinenglish
@fluencyinenglish
@fluencyinenglish
✴️Cornucopia: Abundant supply
(kôr′nə-kō′pē-ə, -nyə-)
Example - "My mother loves to garden, she has a cornucopia of fresh veggies in the backyard."
@fluencyinenglish
@fluencyinenglish
@fluencyinenglish
✴️Inimitable: Unmatched; extremely unique
(ĭ-nĭm′ĭ-tə-bəl)
Example - "No matter how hard I tried, I couldn't recreate the painting of the mountains. It was terribly inimitable, and eventually I gave up."
@fluencyinenglish
@fluencyinenglish
@fluencyinenglish
✴️Coalesce: Fuse together
Example - "The two small fires coalesced and turned into one huge raging forest fire.
✅Sharing is caring
@fluencyinenglish
@fluencyinenglish
@fluencyinenglish
#vocabulary
#phrasalverbs
#advanced_vocabulary
@fluencyinenglish
@fluencyinenglish
@fluencyinenglish
🔹amount to something
/əˈmɑʊnt·tə, -ˌtu/
to add up to, be in total, be equal to, or be the same as
Example: Federal and state costs for building and operating prisons amounted to $25 billion.
Example: The blog amounts to a critique of the U.S. news media.
@fluencyinenglish
@fluencyinenglish
@fluencyinenglish
✴️Cede: To give up control; surrender
(sēd)
Example - "The police officers had to cede control to the FBI agents."
@fluencyinenglish
@fluencyinenglish
@fluencyinenglish
✴️Promenade: Leisurely walk
(prŏm′ə-nād′, -näd′)
Example - "The couple promenaded around town with matching outfits on."
@fluencyinenglish
@fluencyinenglish
@fluencyinenglish
✴️Cornucopia: Abundant supply
(kôr′nə-kō′pē-ə, -nyə-)
Example - "My mother loves to garden, she has a cornucopia of fresh veggies in the backyard."
@fluencyinenglish
@fluencyinenglish
@fluencyinenglish
✴️Inimitable: Unmatched; extremely unique
(ĭ-nĭm′ĭ-tə-bəl)
Example - "No matter how hard I tried, I couldn't recreate the painting of the mountains. It was terribly inimitable, and eventually I gave up."
@fluencyinenglish
@fluencyinenglish
@fluencyinenglish
✴️Coalesce: Fuse together
Example - "The two small fires coalesced and turned into one huge raging forest fire.
✅Sharing is caring
@fluencyinenglish
@fluencyinenglish
@fluencyinenglish
#vocabulary
#phrasalverbs
#advanced_vocabulary
@fluencyinenglish
@fluencyinenglish
@fluencyinenglish
🔹amount to something
/əˈmɑʊnt·tə, -ˌtu/
to add up to, be in total, be equal to, or be the same as
Example: Federal and state costs for building and operating prisons amounted to $25 billion.
Example: The blog amounts to a critique of the U.S. news media.
@fluencyinenglish
@fluencyinenglish
@fluencyinenglish
✴️Cede: To give up control; surrender
(sēd)
Example - "The police officers had to cede control to the FBI agents."
@fluencyinenglish
@fluencyinenglish
@fluencyinenglish
✴️Promenade: Leisurely walk
(prŏm′ə-nād′, -näd′)
Example - "The couple promenaded around town with matching outfits on."
@fluencyinenglish
@fluencyinenglish
@fluencyinenglish
✴️Cornucopia: Abundant supply
(kôr′nə-kō′pē-ə, -nyə-)
Example - "My mother loves to garden, she has a cornucopia of fresh veggies in the backyard."
@fluencyinenglish
@fluencyinenglish
@fluencyinenglish
✴️Inimitable: Unmatched; extremely unique
(ĭ-nĭm′ĭ-tə-bəl)
Example - "No matter how hard I tried, I couldn't recreate the painting of the mountains. It was terribly inimitable, and eventually I gave up."
@fluencyinenglish
@fluencyinenglish
@fluencyinenglish
✴️Coalesce: Fuse together
Example - "The two small fires coalesced and turned into one huge raging forest fire.
✅Sharing is caring
@fluencyinenglish
@fluencyinenglish
@fluencyinenglish
5 phrasal verbs with “PAY”
I shared the questions first on purpose — to make you think before seeing the meanings.
That struggle helps the meanings stick better than passive reading.
If a meaning surprised you, that’s good — it means your brain is actually learning.
#EnglishLearning#PhrasalVerbs#LearnEnglish#RealEnglish