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1
answer

CMD, PowerShell, Bash - What's the difference?

There are differences between them, which ones? I speak Ubuntu Bash. I'm curious because to me they seem to do the same thing!     
asked on 07.08.2016 / 21:08
4
answers

How to join observations of tables that have a different set of variables in R?

In the case below id corresponds to observations contained in two different data frames, where in df1 the observations have the variable x and in df2 the observations have x and z In these cases how to join the two data frames? rbind...
asked on 14.01.2016 / 18:34
5
answers

Get first name with Regular Expression

I need to get the first name with regular expression, but I'm not getting it right. Today I use the code like this: <?php preg_match('/[[:alnum:]]+/i', 'Alisson Acioli', $matches); return $matches[0]; ?>    Output: Alisson When t...
asked on 29.12.2015 / 18:36
2
answers

Tip for code optimization in C

The way I wrote the code below is too long. How to make the code leaner? void mostrasaida(char recebido) { int dadoA [5] = {252, 146, 145, 146, 252}; int dadoB [5] = {255, 201, 201, 201, 182}; //Varios vetores de AaZ int cont=0...
asked on 26.07.2016 / 18:20
2
answers

What is bind? [closed]

I can not find the meaning of Bind, let me explain what this is. I would like an example of Bind with the same java language.     
asked on 13.03.2016 / 19:41
2
answers

How to run a file with PHP?

I wanted to know some code in PHP that makes me open a file .exe , ie a line that makes execute a .exe file from the same server.     
asked on 02.12.2015 / 22:05
3
answers

How to catch a NullReferenceException?

When I test my application, it returns some specific data, but when the requested data is null, this unhandled exception error appears ItriedtocapturehimbutIthinkI'mwrong.HowcanIleaveatreatmentthatwarnsinatextboxthattherequesteddatawasnotfou...
asked on 26.11.2015 / 01:24
2
answers

Why are loops slow in R? How to avoid them?

It is very common to hear (or read) that loops are not efficient in R and should be avoided ( in this link or on another link or same in this ). And proving this statement is simple: numeros <- rnorm(10000) com_loop <- fun...
asked on 26.10.2017 / 14:51
2
answers

Is there a performance benefit on replacing the "==" operator with the "===" operator?

I'm using JSLint to check if the JavaScript source code complies with the encoding rules, and it is returning many suggestions for replacing == (two equal signs) with === (three equal signs) when doing things like comparing id...
asked on 09.04.2018 / 02:38
2
answers

You can concatenate numbers of type int

For example 10 and 12, concatenated would be 1012, this would not be string , it would have to be integer type, can you do that?     
asked on 08.02.2018 / 16:07