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Standardize data columns in R
... a dataframe and all the columns are numeric you can simply call the scale function on the data to do what you want.
dat <- data.frame(x = rnorm(10, 30, .2), y = runif(10, 3, 5))
scaled.dat <- scale(dat)
# check that we get mean of 0 and sd of 1
colMeans(scaled.dat) # faster version of appl...
Why does Boolean.ToString output “True” and not “true”
...Microsoft can really answer that question. However, I'd like to offer some fun facts about it ;)
First, this is what it says in MSDN about the Boolean.ToString() method:
Return Value
Type: System.String
TrueString if the value of this
instance is true, or FalseString if
the value ...
jQuery Scroll To bottom of the page
... answered Jul 10 '15 at 13:35
f123f123
36422 silver badges88 bronze badges
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Git / Bower Errors: Exit Code # 128 & Failed connect
...his is not "fixing" the problem, but you can use
git config --global url."https://".insteadOf git://
to tell git to use HTTPS instead of GIT which worked out for me to install npm dependencies.
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Generic TryParse
... it's simply a matter of calling thusly:
var value = TryParse<int>("123", int.TryParse);
var value2 = TryParse<decimal>("123.123", decimal.TryParse);
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Can the jQuery UI Datepicker be made to disable Saturdays and Sundays (and holidays)?
...r'], [6, 6, 'se'],
[7, 4, 'us'], [8, 17, 'id'], [9, 7, 'br'],
[10, 1, 'cn'], [11, 22, 'lb'], [12, 12, 'ke']
];
function nationalDays(date) {
for (i = 0; i < natDays.length; i++) {
if (date.getMonth() == natDays[i][0] - 1
&& date.getDate() == natDays[i][1]) {
...
Can you supply arguments to the map(&:method) syntax in Ruby?
...
I like this solution, but I think you can have even more fun with it. Instead of defining a with method, define call. Then you can do things like a.map(&:+.(2)) since object.() uses the #call method. And while you're at it, you can write fun things like :+.(2).(3) #=> 5 -...
Does Java read integers in little endian or big endian?
...mats that use some form of Huffman encoding (i.e. all of them). For extra fun, JPEG is "bitwise big-endian" (i.e. the most significant bit is the "first" bit) and LZ is "bitwise little-endian". I once worked on a proprietary compression format that used both formats under the hood. Oh, that was f...
Is there a way to get a collection of all the Models in your Rails app?
...ase. Don't know how you can list all the classes though...
EDIT: Just for fun, I found a way to list all classes
Module.constants.select { |c| (eval c).is_a? Class }
EDIT: Finally succeeded in listing all models without looking at directories
Module.constants.select do |constant_name|
constan...
SVG gradient using CSS
...="url(#gradient)" />
</svg>
See an editable example here:
https://jsbin.com/gabuvisuhe/edit?html,css,output
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