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Generate a random double in a range
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This is generally correct, but beware of its limits. If you do double rangeMax= Double.MAX_VALUE; and double rangeMin= -rangeMax; you will always get an infinite value in return. You might want to check for Double.valueOf(rangeMax-range...
Delete column from pandas DataFrame
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This answer isn't really correct - the pandas developers didn't, but that doesn't mean it is hard to do.
– wizzwizz4
Sep 30 '17 at 9:42
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What is the difference between C++ and Visual C++? [duplicate]
...979 at Bell Labs as an enhancement to the C programming language and originally named "C with Classes". It was renamed to C++ in 1983.
C++ is widely used in the software industry. Some of its application domains include systems software, application software, device drivers, embedded software, high...
Android Studio suddenly cannot resolve symbols
...e imports and AS seems to be telling me it can't find android.support.v4 all of a sudden (offering me the option to remove the unused imports). ( android.support.v7 seems to be fine though).
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How can I use a local image as the base image with a dockerfile?
...ockerfile.
I just realised that I've been using FROM with indexed images all along.
4 Answers
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capturing self strongly in this block is likely to lead to a retain cycle
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Good answer, but I take small issue with you saying: “you can't refer to self or properties on self from within a block that will be strongly retained by self.” This is not strictly true. Please see my answer below. Better to say, “you must take...
Install a .NET windows service without InstallUtil.exe
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You can always fall back to the good old WinAPI calls, although the amount of work involved is non-trivial. There is no requirement that .NET services be installed via a .NET-aware mechanism.
To install:
Open the service manager via OpenSCManager.
Call CreateService...
Converting an object to a string
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JSON.stringify is not suitable for all cases e.g a jQuery reference object of an input field like button etc.
– techie_28
May 18 '16 at 7:45
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How can I convert an image into Base64 string using JavaScript?
...leReader
Load the image as blob via XMLHttpRequest and use the FileReader API to convert it to a dataURL:
function toDataURL(url, callback) {
var xhr = new XMLHttpRequest();
xhr.onload = function() {
var reader = new FileReader();
reader.onloadend = function() {
callback...
How to reshape data from long to wide format
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The reshape comments and similar argument names aren't all that helpful. However, I have found that for long to wide, you need to provide data = your data.frame, idvar = the variable that identifies your groups, v.names = the variables that will become multiple columns in wide f...