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Where is Erlang used and why? [closed]

...ng in its SMS and authentication systems. • Motorola is using Erlang in call processing products in the public-safety industry. • Ericsson uses Erlang in its support nodes, used in GPRS and 3G mobile networks worldwide. The most popular open source Erlang applications include the following: •...
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Warning message: In `…` : invalid factor level, NA generated

... Here is a flexible approach, it can be used in all cases, in particular: to affect only one column, or the dataframe has been obtained from applying previous operations (e.g. not immediately opening a file, or creating a new data frame). First, un-factorize a stri...
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Calculate relative time in C#

...her languages, you will hate yourself for doing logic like this. Just so y'all know... – Nik Reiman May 23 '12 at 14:31 73 ...
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Fluent Validation vs. Data Annotations [closed]

...when used for ASP.NET MVC validatation? They seem to have similar objects, all the way to their object names. Is one related to another? What are their differences? In what way do these differences denote different use cases? ...
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Flask-SQLAlchemy import/context issue

...: # fields here pass And then in your application setup you can call init_app: # apps.application.py from flask import Flask from apps.members.models import db app = Flask(__name__) # later on db.init_app(app) This way you can avoid cyclical imports. This pattern does not necessitate ...
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What are copy elision and return value optimization?

... is an optimization implemented by most compilers to prevent extra (potentially expensive) copies in certain situations. It makes returning by value or pass-by-value feasible in practice (restrictions apply). It's the only form of optimization that elides (ha!) the as-if rule - copy elision can be a...
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Is the NOLOCK (Sql Server hint) bad practice?

... It is occassionally useful, but not normally for production. I use it frequently for pulling out a sample of data to test with or for generating reports where I mostly care about rough order of magnitude where a dirty read won't matter. ...
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.toArray(new MyClass[0]) or .toArray(new MyClass[myList.size()])?

... the result may be different. Benchmark results (score in microseconds, smaller = better): Benchmark (n) Mode Samples Score Error Units c.a.p.SO29378922.preSize 1 avgt 30 0.025 ▒ 0.001 us/op c.a.p.SO29378922.preSize 100 avgt 30 0.15...
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HTTP URL Address Encoding in Java

... @Mohamed: the class I mentioned and used for testing actually is java.net.URI: it worked perfectly (Java 1.6). I would mention the fully qualified class name if it was not the standard Java one and the link points to the documentation of java.net.URI. And, by the comment of Sudhaka...
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How to add multi line comments in makefiles

...efile for debugging reasons, and adding a backslash on every line is not really practical. If you are using GNU make, I suggest you use the ifeq directive with a deliberately false expression. For example: ifeq ("x","y") # here's all your 'commented' makefile content... endif Hope that helps. ...