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How is std::function implemented?
According to the sources I have found, a lambda expression is essentially implemented by the compiler creating a class with overloaded function call operator and the referenced variables as members. This suggests that the size of lambda expressions varies, and given enough references variables tha...
Only read selected columns
...g","Sep","Oct","Nov","Dec"))
dat <- fread("data.txt", drop = c(8:13))
All result in:
> data
Year Jan Feb Mar Apr May Jun
1 2009 -41 -27 -25 -31 -31 -39
2 2010 -41 -27 -25 -31 -31 -39
3 2011 -21 -27 -2 -6 -10 -32
UPDATE: When you don't want fread to return a data.table, use the data.ta...
Python matplotlib multiple bars
How to plot multiple bars in matplotlib, when I tried to call the bar function multiple times, they overlap and as seen the below figure the highest value red can be seen only.
How can I plot the multiple bars with dates on the x-axes?
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几个有趣的Javascript Hack - 创意 - 清泛网 - 专注C/C++及内核技术
...当前网页已经变成编辑模式了。将上述代码中的true改成false重新执行一遍即可恢复。
2. 舞动的图片
javascript：R=0; x1=.1; y1=.05; x2=.25; y2=.24; x3=1.6; y3=.24; x4=300; y4=200; x5=300; y5=200; DI=document.images; DIL=DI.length; function A(){for(i=0; i-DIL;...
Animate text change in UILabel
...seems that you have to specify the fade at each change. So - provided you call the transition each time, this works fine in my test on iOS9.
– Confused Vorlon
Nov 7 '15 at 23:50
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What are all possible pos tags of NLTK?
How do I find a list with all possible pos tags used by the Natural Language Toolkit (nltk)?
8 Answers
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How could the UNIX sort command sort a very large file?
...link goes into more details, but in essence it divides the input up into smaller portions (that fit into memory) and then merges each portion together at the end.
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Loop through all the files with a specific extension
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It will if it actually matches any files. You need to use shopt -s nullglob so that a non-matching pattern expands to the empty sequence rather than be treated literally.
– chepner
Aug 1 '15 at 23:08
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How can I export the schema of a database in PostgreSQL?
... only the schema to stdout as .sql.
For windows, you'll probably want to call pg_dump.exe. I don't have access to a Windows machine but I'm pretty sure from memory that's the command. See if the help works for you too.
shar...
Install tkinter for Python
...stall Tkinter locally to use with system-provided Python. You may build it from sources, but this is usually not the best idea with a binary package-based distro you're apparently running.
It's safer to apt-get install python-tk on your machine(s).
(Works on Debian-derived distributions like for Ub...