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Create an empty data.frame
...is just a bit safer in the sense that you'll have the correct column types from the beginning, hence if your code relies on some column type checking, it will work even with a data.frame with zero rows.
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Byte array to image conversion
...nstead:
using (var ms = new MemoryStream(byteArrayIn))
{
return Image.FromStream(ms);
}
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Which regular expression operator means 'Don't' match this character?
... is "begining of string"
[^a-z] matches any single character that is not from "a" to "z"
^[a-z] means string starts with from "a" to "z"
Reference
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CORS - How do 'preflight' an httprequest?
..." header and 'preflight' requests with and OPTIONS request. I got the idea from this post : Getting CORS working
2 Answers...
How do I break a string over multiple lines?
... this is my very very very\nlong string\n
Here's the official definition from the YAML Spec 1.2
Scalar content can be written in block notation, using a literal style (indicated by “|”) where all line breaks are significant. Alternatively, they can be written with the folded style (denoted ...
How can I remove an entry in global configuration with git config?
...mit but not the other way around by setting core.autocrlf to input:" From: git-scm.com/book/en/v2/…
– colin_froggatt
May 6 '15 at 13:11
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Correct way to convert size in bytes to KB, MB, GB in JavaScript
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From this: (source)
function bytesToSize(bytes) {
var sizes = ['Bytes', 'KB', 'MB', 'GB', 'TB'];
if (bytes == 0) return '0 Byte';
var i = parseInt(Math.floor(Math.log(bytes) / Math.log(1024)));
return Math.round(...
Why are functions in Ocaml/F# not recursive by default?
...s definition inside the body of a new definition. F# inherited this syntax from OCaml.
For example, superceding the function p when computing the Shannon entropy of a sequence in OCaml:
let shannon fold p =
let p x = p x *. log(p x) /. log 2.0 in
let p t x = t +. p x in
-. fold p 0.0
Note ...
Why does the is operator return false when given null?
...entence "is null a string" the answer is no, it is not, which is different from "is null assignable to string"
– Davy8
Oct 3 '11 at 20:22
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Extract first item of each sublist
...ction called itemgetter to return the item at a specific index in a list:
from operator import itemgetter
Pass the itemgetter() function the index of the item you want to retrieve. To retrieve the first item, you would use itemgetter(0). The important thing to understand is that itemgetter(0) i...