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Test if a vector contains a given element
...irst appearance) and %in% (returns a Boolean) functions are designed for this.
v <- c('a','b','c','e')
'b' %in% v
## returns TRUE
match('b',v)
## returns the first location of 'b', in this case: 2
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Access to the path is denied
I know this question was asked many times here, but I can't find a solution to my problem.
I'm trying to save image to the folder in .net c# but get this exception:
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What are the best practices for using a GUID as a primary key, specifically regarding performance?
...UID as the Primary Key in almost all tables and I have read that there are issues about performance when using GUID as Primary Key. Honestly, I haven't seen any problem, but I'm about to start a new application and I still want to use the GUIDs as the Primary Keys, but I was thinking of using a Comp...
What's the right way to pass form element state to sibling/parent elements?
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So, if I'm understanding you correctly, your first solution is suggesting that you're keeping state in your root component? I can't speak for the creators of React, but generally, I find this to be a proper solution.
Maintaining state is one of the reasons (at least I think) that Re...
Random / noise functions for GLSL
As the GPU driver vendors don't usually bother to implement noiseX in GLSL, I'm looking for a "graphics randomization swiss army knife" utility function set, preferably optimised to use within GPU shaders. I prefer GLSL, but code any language will do for me, I'm ok with translating it on my own ...
What is your favorite C programming trick? [closed]
For example, I recently came across this in the linux kernel:
37 Answers
37
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Why are global variables evil? [closed]
I'm trying to find out why the use of global is considered to be bad practice in python (and in programming in general). Can somebody explain? Links with more info would also be appreciated.
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What is [Serializable] and when should I use it?
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What is it?
When you create an object in a .Net framework application, you don't need to think about how the data is stored in memory. Because the .Net Framework takes care of that for you. However, if you want to store the conten...
Confused by python file mode “w+”
...e with a with statement like you should be. Then you'd do something like this to read from your file:
with open('somefile.txt', 'w+') as f:
# Note that f has now been truncated to 0 bytes, so you'll only
# be able to read data that you write after this point
f.write('somedata\n')
f....
Ajax request returns 200 OK, but an error event is fired instead of success
...e header sent by the server. If the conversion fails (e.g. if the JSON/XML is invalid), the error callback is fired.
Your AJAX code contains:
dataType: "json"
In this case jQuery:
Evaluates the response as JSON and returns a JavaScript object. […]
The JSON data is parsed in a strict ma...