Multiprocessing : More processes than cpu.count

Note : I "forayed" into the land of multiprocessing 2 days ago. So my understanding is very basic. I am writing and application for uploads to amazon s3 buckets. In case the file size is larger( 100mb ), Ive implemented parallel uploads using pool from the multiprocessing module. I am using a machine with core i7 , i had a cpu_count of 8 . I was under the impression that if i do p

多处理:比cpu.count更多的进程

注意 :2天前我“进入” multiprocessing 。 所以我的理解是非常基本的。 我正在编写和申请上传到amazon s3桶。 如果文件大小较大( 100mb ),Ive使用multiprocessing模块中的pool实现了并行上传。 我使用的是core i7的机器,我的cpu_count为8 。 我的印象是,如果我做pool = Pool(process = 6)我使用6内核,文件开始上传,前6个部分的上传同时开始。 要查看当process大于cpu_count时会发生什么,我输入了20(意味着我想使

Python 3: send method of generators

I can't understand the send method. I understand that it is used to operate the generator. But the syntax is here: generator.send(value) . I somehow can't catch why the value should become the result of the current yield expression. I prepared an example: def gen(): for i in range(10): X = yield i if X == 'stop': break print("Inside the functi

Python 3:发送器的发送方法

我无法理解send方法。 我知道它是用来操作发生器的。 但语法如下: generator.send(value) 。 我不知道为什么价值应该成为当前yield表达式的结果。 我准备了一个例子: def gen(): for i in range(10): X = yield i if X == 'stop': break print("Inside the function " + str(X)) m = gen() print("1 Outside the function " + str(next(m)) + 'n') print("2 Outside the functi

How do I parallelize a simple Python loop?

This is probably a trivial question, but how do I parallelize the following loop in python? # setup output lists output1 = list() output2 = list() output3 = list() for j in range(0, 10): # calc individual parameter value parameter = j * offset # call the calculation out1, out2, out3 = calc_stuff(parameter = parameter) # put results into correct output list output1.appen

我如何并行化一个简单的Python循环?

这可能是一个微不足道的问题,但我如何在python中并行化下面的循环? # setup output lists output1 = list() output2 = list() output3 = list() for j in range(0, 10): # calc individual parameter value parameter = j * offset # call the calculation out1, out2, out3 = calc_stuff(parameter = parameter) # put results into correct output list output1.append(out1) output2.append(

Can't understand python shallow copy when working with int and str

Python doc about copy The difference between shallow and deep copying is only relevant for compound objects (objects that contain other objects, like lists or class instances): A shallow copy constructs a new compound object and then (to the extent possible) inserts references into it to the objects found in the original. A deep copy constructs a new compound object and then, recursively, in

在处理int和str时无法理解python浅层副本

关于复制的Python文档 浅层和深层复制之间的区别仅与复合对象(包含其他对象的对象,如列表或类实例)相关: 浅拷贝构造一个新的复合对象,然后(尽可能)将引用插入到原始对象中。 深层副本构造一个新的复合对象,然后递归地将副本插入到原始对象中找到的对象。 我认为浅拷贝应该复制列表的引用,因此更新shallow_copy_list也应该更改原始列表,但第一个示例不能按预期工作。 Python 3.6.0(默认,2016年12月24日,08:

What is the best way to copy a list?

This question already has an answer here: How to clone or copy a list? 18 answers If you want a shallow copy (elements aren't copied) use: lst2=lst1[:] If you want to make a deep copy then use the copy module: import copy lst2=copy.deepcopy(lst1) I often use: lst2 = lst1 * 1 If lst1 it contains other containers (like other lists) you should use deepcopy from the copy lib as shown b

什么是复制列表的最佳方式?

这个问题在这里已经有了答案: 如何克隆或复制列表? 18个答案 如果你想要一个浅拷贝(元素不被复制),使用: lst2=lst1[:] 如果您想进行深层复制,请使用复制模块: import copy lst2=copy.deepcopy(lst1) 我经常使用: lst2 = lst1 * 1 如果lst1包含其他容器(如其他列表),则应使用Mark所示的copy lib中的deepcopy。 更新:解释deepcopy >>> a = range(5) >>> b = a*1 >>> a,b ([0

python list.copy shallow vs deep copy

This question already has an answer here: What is the difference between a deep copy and a shallow copy? 30 answers What exactly is the difference between shallow copy, deepcopy and normal assignment operation? 8 answers You've simply misunderstood what "shallow" and "deep" mean in this context. A shallow copy is a copy of the top level of elements only. If any

python list.copy浅vs深拷贝

这个问题在这里已经有了答案: 深拷贝和浅拷贝之间有什么区别? 30个答案 浅拷贝,深拷贝和正常赋值操作的区别究竟是什么? 8个答案 在这种情况下,你简单地误解了“浅”和“深”的含义。 浅拷贝只是元素顶层的副本。 如果这些元素中的任何一个都是自己的列表,这些副本仍然会引用原始列表。 这是l1[:]和l1.copy()所做的。 深层副本是各级副本。 如果任何元素是列表,它们也将被深度复制。 将不会分享任何参考。 这

Set zlim in mplot3D

mpl.rcParams['legend.fontsize'] = 10 fig1 = plt.figure() ax = fig1.gca(projection='3d') ax.plot(tab_C[0], tab_C[1], zs=0, zdir='z', label = "Projection de la trajectoire de C", color='k') ax.plot(tab_M[0], tab_M[1], zs=0, zdir='z', label = "Projection de la trajectoire de M", color='r') for i in range(0,len(tab_t)): ax.plot(tab_C[0][i:i+2], tab_C[1][i:i+2], tab_C[2][i:i+2], color=plt.cm.ra

在mplot3D中设置zlim

mpl.rcParams['legend.fontsize'] = 10 fig1 = plt.figure() ax = fig1.gca(projection='3d') ax.plot(tab_C[0], tab_C[1], zs=0, zdir='z', label = "Projection de la trajectoire de C", color='k') ax.plot(tab_M[0], tab_M[1], zs=0, zdir='z', label = "Projection de la trajectoire de M", color='r') for i in range(0,len(tab_t)): ax.plot(tab_C[0][i:i+2], tab_C[1][i:i+2], tab_C[2][i:i+2], color=plt.cm.ra

the trick to nested structures in pyparsing

I am struggling to parse nested structures with PyParsing. I've searched many of the 'nested' example uses of PyParsing, but I don't see how to fix my problem. Here is what my internal structure looks like: texture_unit optionalName { texture required_val prop_name1 prop_val1 prop_name2 prop_val1 } and here is what my external structure looks like, but it can cont

在pyparsing中嵌套结构的技巧

我正在努力用PyParsing解析嵌套结构。 我搜索了很多PyParsing的'嵌套'示例用法,但我没有看到如何解决我的问题。 以下是我的内部结构: texture_unit optionalName { texture required_val prop_name1 prop_val1 prop_name2 prop_val1 } 这里是我的外部结构看起来像,但它可以包含零个或更多的内部结构。 pass optionalName { prop_name1 prop_val1 prop_name2 prop_val1 texture_unit op

== '

I am coding python in emacs. However, somehow the python interpreter running in emacs manages to surprise me. If I write print() print(__name__) print(__name__=='__main__') if __name__ == '__main__': print("indeed") in an emacs buffer, and tell emacs to start an interpreter and run the content of this buffer, I get a buffer containing Python 3.3.5 (default, Mar 18 2014, 02:00:02) [GCC

=='

我在emacs编码python。 然而,不知何故,运行在emacs上的python解释器让我感到吃惊。 如果我写 print() print(__name__) print(__name__=='__main__') if __name__ == '__main__': print("indeed") 在emacs缓冲区中,并告诉emacs启动一个解释器并运行这个缓冲区的内容,我得到一个缓冲区,其中包含 Python 3.3.5 (default, Mar 18 2014, 02:00:02) [GCC 4.2.1 20070831 patched [FreeBSD]] on freebsd9 Type "help", "

Is there a way to add sections to QListView in PySide or PyQt?

This question is an exact duplicate of this unanswered question, except that I'm using Python. I've got this. And am looking for this. I'm looking for hints as to how to approach this. Here's what I've considered so far. Add "virtual items" to the model itself. I'd rather not do this, in order to keep the model free of view related data. I intend to ad

有没有办法在PySide或PyQt中添加章节到QListView?

这个问题与这个未答复的问题完全相同,除了我在使用Python。 我有这个。 我正在寻找这个。 我正在寻找如何解决这个问题的提示。 这是我迄今为止所考虑的。 将“虚拟物品”添加到模型本身。 我宁愿不这样做,为了保持模型免费的视图相关数据。 我打算在此模型上添加其他视图。 为每个视图添加一个代理模型。 该代理可以添加其他项目并对其进行适当的排序。 虽然比(1)更干净,但我并不完全相信这个原因。 子类QLi