python

Python reorder a sorted list so the highest value is in the middle

由 ♀尐吖头ヾ 提交于 2021-02-20 09:23:28
问题 I need to reorder a sorted list so the "middle" element is the highest number. The numbers leading up to the middle are incremental, the numbers past the middle are in decreasing order. I have the following working solution, but have a feeling that it can be done simpler: foo = range(7) bar = [n for i, n in enumerate(foo) if n % 2 == len(foo) % 2] bar += [n for n in reversed(foo) if n not in bar] bar [1, 3, 5, 6, 4, 2, 0] 回答1: how about: foo[len(foo)%2::2] + foo[::-2] In [1]: foo = range(7)

Python reorder a sorted list so the highest value is in the middle

由 我的未来我决定 提交于 2021-02-20 09:20:40
问题 I need to reorder a sorted list so the "middle" element is the highest number. The numbers leading up to the middle are incremental, the numbers past the middle are in decreasing order. I have the following working solution, but have a feeling that it can be done simpler: foo = range(7) bar = [n for i, n in enumerate(foo) if n % 2 == len(foo) % 2] bar += [n for n in reversed(foo) if n not in bar] bar [1, 3, 5, 6, 4, 2, 0] 回答1: how about: foo[len(foo)%2::2] + foo[::-2] In [1]: foo = range(7)

Testing aiohttp client with unittest.mock.patch

由 倾然丶 夕夏残阳落幕 提交于 2021-02-20 09:19:53
问题 I've written a simple HTTP client using aiohttp and I'm trying to test it by patching aiohttp.ClientSession and aiohttp.ClientResponse . However, it appears as though the unittest.mock.patch decorator is not respecting my asynchronous code. At a guess, I would say it's some kind of namespacing mismatch. Here's a minimal example: from aiohttp import ClientSession async def is_ok(url:str) -> bool: async with ClientSession() as session: async with session.request("GET", url) as response: return

Changing colours of an area in an image using opencv in python

由 北城余情 提交于 2021-02-20 09:19:46
问题 I have a picture were I want to change all white-ish pixels to grey, but only for a certain area of the image. Example picture, I just want to change the picture outside of the red rectangle, without changing the image within the red rectangle: I already have the general code, which was part of someone elses Stackoverflow question, that changes the colour of every white pixel instead of only just the one outside of an area. image = cv.imread("meme 2.jpg") hsv = cv.cvtColor(image, cv.COLOR

Changing colours of an area in an image using opencv in python

由 天大地大妈咪最大 提交于 2021-02-20 09:19:41
问题 I have a picture were I want to change all white-ish pixels to grey, but only for a certain area of the image. Example picture, I just want to change the picture outside of the red rectangle, without changing the image within the red rectangle: I already have the general code, which was part of someone elses Stackoverflow question, that changes the colour of every white pixel instead of only just the one outside of an area. image = cv.imread("meme 2.jpg") hsv = cv.cvtColor(image, cv.COLOR

Testing aiohttp client with unittest.mock.patch

由 天大地大妈咪最大 提交于 2021-02-20 09:18:29
问题 I've written a simple HTTP client using aiohttp and I'm trying to test it by patching aiohttp.ClientSession and aiohttp.ClientResponse . However, it appears as though the unittest.mock.patch decorator is not respecting my asynchronous code. At a guess, I would say it's some kind of namespacing mismatch. Here's a minimal example: from aiohttp import ClientSession async def is_ok(url:str) -> bool: async with ClientSession() as session: async with session.request("GET", url) as response: return

efficient way to find several rows above and below a subset of data

由 送分小仙女□ 提交于 2021-02-20 09:04:08
问题 I'm wondering if there's an efficient way to get X number of rows below and above a subset of rows. I've created a basic implementation below, but I'm sure there's a better way. The subset that I care about is buyindex, which is the indices of rows that have the buy signal. I want to get several rows above and below the sellindex to verify that my algorithm is working correctly. How do I do it in an efficient way? My way seems roundabout. buyindex = list(data2[data2['buy'] == True].index)

json.dumps、json.dump、json.loads、json.load的区别

由 人盡茶涼 提交于 2021-02-20 08:54:54
json 模块提供了一种很简单的方式来编码和解码JSON数据。 其中两个主要的函数是 json.dumps() 和 json.loads() 下面是如何将Python数据结构转换为json import json data = { " name " :liu, " shares " :11 } str = json.dumps(data) 下面演示如何将一个JSON编码的字符串转换回一个Python数据结构： json_data = json.loads(json_str) 如果你要处理的是文件而不是字符串，你可以使用 json.dump() 和 json.load() 来编码和解码JSON数据。例如： # writing json data with open( ' data.json ' , ' w ' ) as f : json.dump(data,f) -- 把data文件中的字典转换为json 字符串 写入到 data.json文件中 # reading json data with open( ' data.json ' , ' r ' ) as f : json.load(f) --从文件data.json中读取json字符串，转换为python数据结构例如字典 来源： oschina 链接： https://my.oschina.net/u/4274927/blog

python中json.load()、json.loads()、json.dump()、json.dumps()的区别

由 生来就可爱ヽ(ⅴ＜●) 提交于 2021-02-20 08:39:37
json.load()从文件中读取json字符串 json.loads()将json字符串转换为字典类型 json.dumps()将python中的字典类型转换为字符串类型 json.dump()将json格式字符串写到文件中 1.json.load() with open( ' text.json ' , ' r ' ,encoding= ' utf-8 ' ) as f : print(json.load(f)) { "name": "anthony", "sex": "man" } 2.json.loads() #定义字典类型字符串 content = '{"name":"anthony","sex":"man"}' print type(json.loads(content)) print json.load(content) <class 'dict'> {"name":"anthony","sex":"man"} 3.json.dumps() content = {"name":"anthony","sex":"man"} print type(json.dumps(content)) print json.dump(content) <class 'str'> '{"name":"anthony","sex":"man"}' 4.json.dump() content

How to load Pickle file in chunks?

由 会有一股神秘感。 提交于 2021-02-20 08:34:02
问题 Is there any option to load a pickle file in chunks? I know we can save the data in CSV and load it in chunks. But other than CSV, is there any option to load a pickle file or any python native file in chunks? 来源： https://stackoverflow.com/questions/59983073/how-to-load-pickle-file-in-chunks
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