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combinations between two lists?
...-length tuples, all possible
| orderings, no repeated elements
-----------------------------------------+----------------------------------------
combinations(p, r) | r-length tuples, in sorted order, no
...
What's the fastest way to merge/join data.frames in R?
...- data.frame(d1, g1, g2)
library(rbenchmark)
benchmark(replications = 1, order = "elapsed",
merge = merge(d1, d2),
plyr = join(d1, d2),
data.table = {
dt1 <- data.table(d1, key = "x")
dt2 <- data.table(d2, key = "x")
data.frame( dt1[dt2,list(x,y1,y2=dt2$y2)] )
...
Change a Django form field to a hidden field
...get the value.
also you may prefer to use in the view:
form.fields['field_name'].widget = forms.HiddenInput()
but I'm not sure it will protect save method on post.
Hope it helps.
share
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improv...
What is the fastest way to check if a class has a function defined?
...tr() to get the attribute, and callable() to verify it is a method:
invert_op = getattr(self, "invert_op", None)
if callable(invert_op):
invert_op(self.path.parent_op)
Note that getattr() normally throws exception when the attribute doesn't exist. However, if you specify a default value (None...
How do I import other TypeScript files?
...ler as follows:
tsc --module amd app.ts
This then gets compiled to
var __extends = this.__extends || function (d, b) {
function __() { this.constructor = d; }
__.prototype = b.prototype;
d.prototype = new __();
}
define(["require", "exports", 'moo'], function(require, exports, __moo_...
How to serve static files in Flask
...entation Flask describes returning static files. Yes, I could use render_template but I know the data is not templatized. I'd have thought send_file or url_for was the right thing, but I could not get those to work. In the meantime, I am opening the files, reading content, and rigging up a ...
How to change Git log date formats
...ke:
git config --global alias.lg "log --graph --decorate
-30 --all --date-order --date=format:'%Y-%m-%d %H:%M:%S'
--pretty=format:'%C(cyan)%h%Creset %C(black bold)%ad%Creset%C(auto)%d %s'"
I haven't been able to find this in documentation anywhere (if someone knows where to find it, please comme...
std::vector performance regression when enabling C++11
...lts are identical:
(I am compiling your original code, with container.push_back(Item());)
$ g++ -std=c++11 -O3 -flto regr.cpp && perf stat -r 10 ./a.out
Performance counter stats for './a.out' (10 runs):
35.426793 task-clock # 0.986 CPUs utilized (...
What is the GAC in .NET?
... <DIR> GAC
06/17/2009 04:22 PM <DIR> GAC_32
06/17/2009 04:22 PM <DIR> GAC_64
06/17/2009 04:22 PM <DIR> GAC_MSIL
...snip...
0 File(s) 0 bytes
9 Dir(s) 90,538,311,680 bytes free
C:\Wi...
How to install Boost on Ubuntu
....55 but feel free to change or manually download yourself:
wget -O boost_1_55_0.tar.gz https://sourceforge.net/projects/boost/files/boost/1.55.0/boost_1_55_0.tar.gz/download
tar xzvf boost_1_55_0.tar.gz
cd boost_1_55_0/
Get the required libraries, main ones are icu for boost::regex support:
su...