小编Ben*_*een的帖子

为什么,在硬件执行操作的最低级别和所涉及的一般底层操作(即:运行代码时所有编程语言的实际实现的一般性),矢量化通常比循环更快？

当使用矢量化时,计算机在循环时做了什么(我说的是计算机执行的实际计算,而不是程序员编写的计算),或者它有什么不同的做法？

我一直无法说服自己为什么差异应该如此重要.我可能会说服矢量化代码在某处削减一些循环开销,但计算机仍然必须执行相同数量的操作,不是吗？例如,如果我们将大小为N的向量乘以标量,我们将使用N次乘法执行任一方式,不是吗？

使用Anaconda环境时,我无法启动Jupyter在笔记本电脑上工作.我可以在没有环境的情况下这样做,但我需要能够使用环境.这是我做的和我得到的错误:

ben@ben-K60IJ:~/surveillance_sound_classifier/surveillance_sound_classifier$ source activate EECS352
discarding /home/ben/anaconda/bin from PATH
prepending /home/ben/anaconda/envs/EECS352/bin to PATH
(EECS352)ben@ben-K60IJ:~/surveillance_sound_classifier/surveillance_sound_classifier$ jupyter notebook
Traceback (most recent call last):
  File "/home/ben/anaconda/envs/EECS352/bin/jupyter-notebook", line 4, in <module>
import notebook.notebookapp
  File "/home/ben/anaconda/envs/EECS352/lib/python2.7/site-packages/notebook/notebookapp.py", line 61, in <module>
from .services.contents.manager import ContentsManager
  File "/home/ben/anaconda/envs/EECS352/lib/python2.7/site-packages/notebook/services/contents/manager.py", line 16, in <module>
from nbformat import sign, validate, ValidationError
  File "/home/ben/anaconda/envs/EECS352/lib/python2.7/site-packages/nbformat/__init__.py", line 33, in <module>
from .validator import validate, ValidationError
  File "/home/ben/anaconda/envs/EECS352/lib/python2.7/site-packages/nbformat/validator.py", line 21, in <module>
raise ImportError(str(e) + verbose_msg)
ImportError: No module named functools32

Jupyter notebook format …

有没有办法获取列表的索引,哪个映射函数？我已经让地图几乎可以工作,但我能够访问long_words列表中的 特定项目

# full_chunk is a very long string of plaintext (eg:pages from a book)
# long_words is a list of words for which I wish to substitute other things

# works
for x in xrange(len(long_words)):
    full_chunk = full_chunk.replace(long_words[x],str(x))

# doesn't work :(
subber = lambda a,b,c: a.replace(b,c)
map(subber(full_chunk,long_words[long_words.index(x)],long_words.index(x)),long_words)

目前,我只是希望能够代替每一个字每一个出现的long_words,出现在full_chunk与所述字中的索引long_words列表.例如:

# example input
long_words = ['programming','pantaloons']
full_chunk = 'While programming, I prefer to wear my most vividly-hued pantaloons.'

# desired output (which …

更新:感谢JohnnyHK的回答,我的问题已经解决了!

初步问题:为什么我收到以下错误消息的任何想法？请注意,即使程序正常运行,"我们已连接"行之前的所有内容都会打印出来.

DEBUG=cfcwebportal:* ./bin/www
[Error: /home/ben/Code For Chicago/cfcwebportal/node_modules
/mongoose/node_modules/mongodb/node_modules/mongodb-core/node_modules/bson/node_modules/bson-ext/build/Release/bson.node: invalid ELF header]
js-bson: Failed to load c++ bson extension, using pure JS version
[Error: /home/ben/Code For Chicago/cfcwebportal/node_modules/mongoose/node_modules/mongodb/node_modules/mongodb-core/node_modules/bson/node_modules/bson-ext/build/Release/bson.node: invalid ELF header]
js-bson: Failed to load c++ bson extension, using pure JS version
[Error: /home/ben/Code For Chicago/cfcwebportal/node_modules/mongoose/node_modules/mongodb/node_modules/mongodb-core/node_modules/bson/node_modules/bson-ext/build/Release/bson.node: invalid ELF header]
js-bson: Failed to load c++ bson extension, using pure JS version
[Error: /home/ben/Code For Chicago/cfcwebportal/node_modules/mongoose/node_modules/mongodb/node_modules/mongodb-core/node_modules/bson/node_modules/bson-ext/build/Release/bson.node: invalid ELF header]
js-bson: Failed to load c++ bson extension, using pure JS version
We …