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Remove columns from dataframe where ALL values are NA
...m.time({df1 <- bd[,colSums(is.na(bd) < nrow(bd))]})
# error -- can't allocate vector of size ...
system.time({df2 <- bd[, !apply(is.na(bd), 2, all)]})
# error -- can't allocate vector of size ...
system.time({df3 <- Filter(function(x)!all(is.na(x)), bd)})
## user system elapsed
## 0.26...
Submit HTML form on self page
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I used <?php $_PHP_SELF ?> and got the error that action cannot be blank, i guess ill just leave it off
– Drewdin
Feb 18 '15 at 12:04
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Finish an activity from another activity
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It shows this error "Syntax error on tokens, AnnotationName expected instead" on "registerReceiver(broadcast_reciever, new IntentFilter("finish_activity"));". What's wrong?
– Behzad
Nov 13 '12 at 8:29
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How do I reformat HTML code using Sublime Text 2?
... if your file is saved with an extension that contains HTML like .html or .php.
If you do this often, you may find this key mapping useful:
{ "keys": ["ctrl+shift+r"], "command": "reindent" , "args": { "single_line": false } }
If your file is not saved (e.g. you just pasted in a snippet to a new...
Appending a vector to a vector [duplicate]
... = orig;
std::copy(v.begin(), v.end(), std::back_inserter(v));
// std::bad_alloc exception is generated
// GOOD, but I can't guarantee it will work with any STL:
v = orig;
v.reserve(v.size()*2);
v.insert(v.end(), v.begin(), v.end());
// Now v contains: { "first", "second", "first", "second" }
// G...
Long press on UITableView
...view:
UILongPressGestureRecognizer *lpgr = [[UILongPressGestureRecognizer alloc]
initWithTarget:self action:@selector(handleLongPress:)];
lpgr.minimumPressDuration = 2.0; //seconds
lpgr.delegate = self;
[self.myTableView addGestureRecognizer:lpgr];
[lpgr release];
Then in the gesture handler:
...
Should I use 'has_key()' or 'in' on Python dicts?
...() must construct and destroy a temporary object, complete with the memory allocation that entails, where x in d.keys() is just doing an arithmetic operation (computing the hash) and doing a lookup. Note that d.keys() is only about 10 times as long as this, which is still not long really. I haven't ...
PHP: Storing 'objects' inside the $_SESSION
... is made, the class declaration/definition has already been encountered by PHP or can be found by an already-installed autoloader. otherwise it would not be able to deserialize the object from the session store.
share
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Read each line of txt file to new array element
... file should either be stored on memory cache, or even in a database. Even PHP stores the content of parsed files. I mean, we're far from PHP 4.3
– Yanick Rochon
Jul 16 at 2:32
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Are the days of passing const std::string & as a parameter over?
...ith `str`.
m_str = str;
}
Hello, copy constructor and potential memory allocation (ignore the Short String Optimization (SSO)). C++11's move semantics are supposed to make it possible to remove needless copy-constructing, right? And A passes a temporary; there's no reason why C should have to co...