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Is there a simple way to delete a list element by value?
I want to remove a value from a list if it exists in the list (which it may not).
21 Answers
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How do I revert a Git repository to a previous commit?
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This depends a lot on what you mean by "revert".
Temporarily switch to a different commit
If you want to temporarily go back to it, fool around, then come back to where you are, all you have to do is check out the desired commit:
# This will detach your HEAD, that is, leave you with no branch check...
How to cast an Object to an int
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If you're sure that this object is an Integer :
int i = (Integer) object;
Or, starting from Java 7, you can equivalently write:
int i = (int) object;
Beware, it can throw a ClassCastException if your object isn't an Int...
How can I use optional parameters in a T-SQL stored procedure?
... creating a stored procedure to do a search through a table. I have many different search fields, all of which are optional. Is there a way to create a stored procedure that will handle this? Let's say I have a table with four fields: ID, FirstName, LastName and Title. I could do something like...
Java: Detect duplicates in ArrayList?
...into a Set (using the Set(Collection) constructor or Set.addAll), then see if the Set has the same size as the ArrayList.
List<Integer> list = ...;
Set<Integer> set = new HashSet<Integer>(list);
if(set.size() < list.size()){
/* There are duplicates */
}
Update: If I'm un...
Fragment onCreateView and onActivityCreated called twice
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public void onTabSelected(Tab tab, FragmentTransaction ft) {
if (mFragment == null) {
mFragment = Fragment.instantiate(mActivity, mClass.getName());
ft.replace(android.R.id.content, mFragment, mTag);
} else {
if (mFragment.isDetached()) {
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Javascript shorthand ternary operator
...ber || 1;
Something like that what you're looking for, where it defaults if undefined?
var foo = bar || 1; // 1
var bar = 2;
foo = bar || 1; // 2
By the way, this works for a lot of scenarios, including objects:
var foo = bar || {}; // secure an object is assigned when bar is absent
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How can I print variable and string on same line in Python?
I am using python to work out how many children would be born in 5 years if a child was born every 7 seconds. The problem is on my last line. How do I get a variable to work when I'm printing text either side of it?
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Check if null Boolean is true results in exception
...s any other object.
In your particular case, your Boolean is null and the if statement triggers an implicit conversion to boolean that produces the NullPointerException. You may need instead:
if(bool != null && bool) { ... }
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Cleaning `Inf` values from an R dataframe
...ame]])), j = .name,value =NA)))
Or using column numbers (possibly faster if there are a lot of columns):
for (j in 1:ncol(DT)) set(DT, which(is.infinite(DT[[j]])), j, NA)
Timings
# some `big(ish)` data
dat <- data.frame(a = rep(c(1,Inf), 1e6), b = rep(c(Inf,2), 1e6),
c = ...