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Pipe subprocess standard output to a variable [duplicate]
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@Insomaniacal In this case, I knew usage is generally dumped to stderr. But in general, a simple test is to cmd > /dev/null if you still see output it's going to stderr. Confirm by piping stderr cmd 2> /dev/null and it should vanish into /dev/null.
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Could not find an implementation of the query pattern
...ection using LINQ.
First I add a new LINQ to SQL class, and drag my table called "tblPersoon" into it.
9 Answers
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How to select the rows with maximum values in each group with dplyr? [duplicate]
...icated maximum values present. Otherwise, the filter approach would return all maximum values (rows) per group while the OP's ddply approach with which.max would only return one maximum (the first) per group. To replicate that behavior, another option is to use slice(which.max(value)) in dplyr.
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javascript check for not null
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while technically this works, a double not (!!) is a programming faux-pas. It is really the equivalent of if(val), which is much clearer to read. I would stick to that (fyi Ujwal, !!val should technically work in C or C++ also) see here f...
What is the purpose of Order By 1 in SQL select statement?
...is only has the sql tag. In Standard SQL only column correlation names are allowed in the OREDER BY clause because, in theory, the table correlation names are out of scope i.e. should be ORDER BY PAYMENT_DATE;. Of course, not all SQL implementations conform to Standards.
– oned...
What does Java option -Xmx stand for? [duplicate]
...it says,
-Xmxn
Specify the maximum size, in bytes, of the memory allocation pool. This value must a multiple of 1024 greater than 2MB. Append the letter k or K to indicate kilobytes, or m or M to indicate megabytes. The default value is 64MB. The upper limit for this value will be approxim...
Page redirect after certain time PHP
...ect you to wherever.php in 5 seconds
Remember that header() must be called before any actual output is sent, either by normal HTML tags, blank lines in a file, or from PHP. It is a very common error to read code with include, or require, functions, or another file access function, and have spa...
SQLite in Android How to update a specific row
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It's actually a walk-around. The Third param of db.update() should be the where clause only, and the fourth is the actual condition values. In this case, the line should be: myDB.update(TableName, cv, "_id=?", new String[]{id}). SQLit...
Difference between and
...s will not submit a form - they don't do anything by default. They're generally used in conjunction with JavaScript as part of an AJAX application.
<input type="submit"> buttons will submit the form they are in when the user clicks on them, unless you specify otherwise with JavaScript.
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Persist javascript variables across pages? [duplicate]
...mp; sessionStorage of HTML5. These are supported in the latest versions of all modern browsers, and are much easier to use and less fiddly than cookies.
http://www.w3.org/TR/2009/WD-webstorage-20091222/
https://www.w3.org/TR/webstorage/. (second edition)
Here are some sample code for setting and ...