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Convert a list to a data frame
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Update July 2020:
The default for the parameter stringsAsFactors is now default.stringsAsFactors() which in turn yields FALSE as its default.
Assuming your list of lists is called l:
df <- data.frame(matrix(unlist(l), nrow=length(l), byrow=T))
The above will convert all character columns...
Missing Push Notification Entitlement
...point of getting to the final "Submit" button. You should see this app was now built with the new provisioning profile you created in member center. Cancel out of this now.
Go back to the Apple member center and delete the new provisioning profile you created in step 1.
Back in Xcode, refresh your p...
How to detect if multiple keys are pressed at once using JavaScript?
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Note: keyCode is now deprecated.
Multiple keystroke detection is easy if you understand the concept
The way I do it is like this:
var map = {}; // You could also use an array
onkeydown = onkeyup = function(e){
e = e || event; // to deal w...
What is the curiously recurring template pattern (CRTP)?
...ss A : public X<A> {...};
It is curiously recurring, isn't it? :)
Now, what does this give you? This actually gives the X template the ability to be a base class for its specializations.
For example, you could make a generic singleton class (simplified version) like this
template <cl...
How to download source in ZIP format from GitHub?
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not without using the Github API as far as I know.
– Christoph
Feb 11 '13 at 15:25
add a comment
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Adding images or videos to iPhone Simulator
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Note - while this is valid, and works, I think Koen's solution below is now a better one, since it does not require rebooting the simulator.
Identify your simulator by going to xCode->Devices, selecting your simulator, and checking the Identifier value.
Go to
~/Library/Developer/CoreSimula...
Difference between Covariance & Contra-variance
...s T → IE<T>. Notice that this is a "thin arrow".
With me so far?
Now let's consider a relation. There is an assignment compatibility relationship between pairs of types in the first set. A value of type Tiger can be assigned to a variable of type Animal, so these types are said to be "assi...
“Conversion to Dalvik format failed with error 1” on external JAR
...erly build it.
In other ways this may be occurred if you accidentally or knowingly edit/ add any thing in the class path file manually .In certain cases we may add android.jar path manually to classpath file for generating java doc.On removing the that after javadoc generated code will works fine.P...
How many and which are the uses of “const” in C++?
...ect remain the same. Once one of the object changes data, you however need now two versions: One for the original, and one for the copy. That is, you copy on a write to either object, so that they now both have their own version.
Using code:
int main() {
string const a = "1234";
string co...
Cannot push to Git repository on Bitbucket
...trange error. I've used Git before on Bitbucket but I just reformatted and now I can't seem to get Git to work. After doing a commit, I had to add my email and name to the globals, but then it committed just fine.
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