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What is the difference between quiet NaN and signaling NaN?
I have read about floating-point and I understand that NaN could result from operations. But I can't understand what these are concepts exactly. What is the difference between them?
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How to change a django QueryDict to Python Dict?
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queryDict.iterlists() is making a list value from each key, maybe because you spect lists?, queryDict.iteritems() if you know that querydict does not contains list.
– panchicore
Mar 7 '13 at 23:06
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Bomb dropping algorithm
...hat there is no point bombing layer 1, because the
"blast radius" you get from doing so is always contained within the blast radius of
another square from layer 2. You should be able to easily convince yourself of this.
So, we can reduce the problem to finding an optimal way to bomb away the per...
Android List View Drag and Drop sort
...plement for RecyclerView with ItemTouchHelper. Just override onMove method from ItemTouchHelper.Callback:
@Override
public boolean onMove(RecyclerView recyclerView, RecyclerView.ViewHolder viewHolder, RecyclerView.ViewHolder target) {
mMovieAdapter.swap(viewHolder.getAdapterPosition(), target....
What is the recommended way to delete a large number of items from DynamoDB?
...as usual, see the ExclusiveStartKey parameter:
Primary key of the item from which to continue an earlier query. An
earlier query might provide this value as the LastEvaluatedKey if that
query operation was interrupted before completing the query; either
because of the result set size or th...
How to assign Profile values?
...e. directly... the strongly-typed class is not magically generated for you from the Web.config file, so you have to roll your own.
The sample code in MSDN assumes you are using a Web Site Project, and they tell you just to add a <profile> section to your Web.config and party on with Profile.p...
Make virtualenv inherit specific packages from your global site-packages
...But for some reason I do not know there was a package that was beeing used from the global system. Using pip install -I for the package from inside the virtualenv didn't work. I finally ended up uninstalling temporarily the package both from the virtualenv and global system, Then I could install it ...
Remove Last Comma from a string
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you can remove last comma from a string by using slice() method, find the below example:
var strVal = $.trim($('.txtValue').val());
var lastChar = strVal.slice(-1);
if (lastChar == ',') {
strVal = strVal.slice(0, -1);
}
Here is an Example
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Extracting numbers from vectors of strings
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Update
Since extract_numeric is deprecated, we can use parse_number from readr package.
library(readr)
parse_number(years)
Here is another option with extract_numeric
library(tidyr)
extract_numeric(years)
#[1] 20 1
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Why there is no ConcurrentHashSet against ConcurrentHashMap
...no built in type for ConcurrentHashSet because you can always derive a set from a map. Since there are many types of maps, you use a method to produce a set from a given map (or map class).
Prior to Java 8, you produce a concurrent hash set backed by a concurrent hash map, by using Collections.newS...