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Factors in R: more than an annoyance?
...ls(x)
levels(x$Species)
# [1] "setosa"
This is how to keep levels you've selected out from getting in ggplot legends.
Internally, factors are integers with an attribute level character vector (see attributes(iris$Species) and class(attributes(iris$Species)$levels)), which is clean. If you had to ...
is of a type that is invalid for use as a key column in an index
...ey nvarchar(max)
)
RETURNS bit
AS
BEGIN
declare @res bit
if exists(select * from key_value where [key] = @key)
set @res = 0
else
set @res = 1
return @res
END
But note that a native index is more performant than a check constraint so unless you really can't specify ...
how to install gcc on windows 7 machine?
...ain Cygwin page. What is tricky about the installer is making sure you are selecting the right packages. From the instructions, which has this to say about gcc: "By default, setup.exe will install only the packages in the Base category and their dependencies, resulting in a minimal Cygwin installati...
Center a map in d3 given a geoJSON object
...ction
In code:
var width = 300;
var height = 400;
var vis = d3.select("#vis").append("svg")
.attr("width", width).attr("height", height)
d3.json("nld.json", function(json) {
// create a first guess for the projection
var center = d3.geo.centroid(json)
var scale...
Windows batch: formatted date into variable
..."Install MS SQL Server, connect with a SQL Client, and execute the command SELECT CONVERT(VARCHAR(16), GETDATE(), 112)".
– isapir
Oct 13 '17 at 20:38
2
...
How to serialize SqlAlchemy result to JSON?
...oded before, it will encode it as 'None'.
A recursive, possibly-circular, selective implementation
Another alternative, probably better, is to be able to specify the fields you want to expand:
def new_alchemy_encoder(revisit_self = False, fields_to_expand = []):
_visited_objs = []
class ...
How to do date/time comparison
...lso occurs within a range of times. In this model, I could not simply just select the oldest date, youngest time/latest date, latest time and Unix() seconds compare them. I'd really appreciate any suggestions.
...
How to read data from a zip file without having to unzip the entire file
...ression, Generally, you can make simple parsing of such entries in stream, select needed file, copy header + compressed file data to other file, and call unzip on that part (if you don't want to deal with the whole Zip decompression code or library).
...
Push existing project into Github
...s for your existing project.
"Add New Local Repository" in repositories.
Select your existing folder. It'll ask if you want to do that, say yes.
Once done, you'll see a list of all your files, etc. Commit them.
Go to Repositories and Publish (this will create the new repo on GitHub for you, if yo...
How to put Google Maps V2 on a Fragment using ViewPager
...le way
first log in to your google account and visit google libraries and select Google Maps Android API
dependency found in android studio default map activity :
compile 'com.google.android.gms:play-services:10.0.1'
put your key into android mainifest file under application like below
in Andr...