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How to get position of a certain element in strings vector, to use it as an index in ints vector?
I am trying to get the index of an element in a vector of strings , to use it as an index in another vector of int type, is this possible ?
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Adding a column to a data.frame
..." section of the relevant help text, [[.data.frame.
Data frames can be indexed in several modes. When [ and [[ are used with a single vector index (x[i] or x[[i]]), they index the data frame as if it were a list.
my.dataframe["new.col"] <- a.vector
my.dataframe[["new.col"]] <- a.vector
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Does Foreign Key improve query performance?
...t least in SQL Server, the creation of an FK does not create an associated index, and you should create indexes on all FK fields to improve look up times.
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angular ng-repeat in reverse
..."alert in alerts.slice().reverse()" type="alert.type" close="alerts.splice(index, 1)">{{$index + 1}}: {{alert.msg}}</alert>
Update:
My answer was OK for old version of Angular.
Now, you should be using
ng-repeat="friend in friends | orderBy:'-'"
or
ng-repeat="friend in friends | ord...
In git, is there a simple way of introducing an unrelated branch to a repository?
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This doesn't do exactly what the asker wanted, because it populates the index and the working tree from <start_point> (since this is, after all, a checkout command). The only other action necessary is to remove any unwanted items from the working tree and index. Unfortunately, git reset --h...
Maintain/Save/Restore scroll position when returning to a ListView
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Try this:
// save index and top position
int index = mList.getFirstVisiblePosition();
View v = mList.getChildAt(0);
int top = (v == null) ? 0 : (v.getTop() - mList.getPaddingTop());
// ...
// restore index and position
mList.setSelectionFrom...
How to create a HashMap with two keys (Key-Pair, Value)?
...HashMap. But I want to access the elements from the HashMap based on Array Index. Something like:
12 Answers
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How to replace NaN values by Zeroes in a column of a Pandas Dataframe?
... Thanks. Is my understanding correct that in that answer an "indexer that sets" is the outermost indexing operation (executed just before the assignment. So any assignment that only uses a single indexer is guaranteed to be safe, making your code safe?
– max
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How to get arguments with flags in Bash
...arrays
declare -A arguments=();
declare -A variables=();
# declaring an index integer
declare -i index=1;
# any variables you want to use here
# on the left left side is argument label or key (entered at the command line along with it's value)
# on the right side is the variable name the value ...
How to unstage large number of files without deleting the content
...you have a pristine repo (or HEAD isn't set)[1] you could simply
rm .git/index
Of course, this will require you to re-add the files that you did want to be added.
[1] Note (as explained in the comments) this would usually only happen when the repo is brand-new ("pristine") or if no commits ha...