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Linear Regression and group by in R
...or each state then doing the regression inside the loop and adding the results of each regression to a vector. That does not seem very R-like, however. In SAS I would do a 'by' statement and in SQL I would do a 'group by'. What's the R way of doing this?
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Create a completed Task
I want to create a completed Task (not Task<T> ). Is there something built into .NET to do this?
8 Answers
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NULL values inside NOT IN clause
...e 3 = 1 or 3 = 2 or 3 = 3 or 3 = null
Since 3 = 3 is true, you get a result.
Query B is the same as:
select 'true' where 3 <> 1 and 3 <> 2 and 3 <> null
When ansi_nulls is on, 3 <> null is UNKNOWN, so the predicate evaluates to UNKNOWN, and you don't get any rows.
When...
PHP Get all subdirectories of a given directory
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you can use glob() with GLOB_ONLYDIR option
or
$dirs = array_filter(glob('*'), 'is_dir');
print_r( $dirs);
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Too many 'if' statements?
... can use a table for such a limited number of outcomes:
final int[][] result = new int[][] {
{ 0, 0, 1, 2 },
{ 0, 0, 2, 1 },
{ 2, 1, 3, 3 },
{ 1, 2, 3, 3 }
};
return result[one][two];
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How can I process each letter of text using Javascript?
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If the order of alerts matters, use this:
for (var i = 0; i < str.length; i++) {
alert(str.charAt(i));
}
If the order of alerts doesn't matter, use this:
var i = str.length;
while (i--) {
alert(str.charAt(i));
}
var str = 'This is my string';
function matters() {
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Who architected / designed C++'s IOStreams, and would it still be considered well-designed by today'
...al ill-conceived ideas found their way into the standard: auto_ptr, vector<bool>, valarray and export, just to name a few. So I wouldn't take the presence of IOStreams necessarily as a sign of quality design.
IOStreams have a checkered history. They are actually a reworking of an earlier stre...
What do the makefile symbols $@ and $< mean?
What do the $@ and $< do exactly?
6 Answers
6
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Making a mocked method return an argument that was passed to it
...ication.class);
when(mock.myFunction(anyString())).thenAnswer(new Answer<String>() {
@Override
public String answer(InvocationOnMock invocation) throws Throwable {
Object[] args = invocation.getArguments();
return (String) args[0];
}
});
assertEquals("someString"...
.Net picking wrong referenced assembly version
...s?
Can you put in a binding redirect in your web.config file like this?
<dependentAssembly>
<assemblyIdentity name="Telerik" publicKeyToken="121fae78165ba3d4"/>
<bindingRedirect oldVersion="1.0.0.0" newVersion="2.0.0.0"/>
</dependentAssembly>
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