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PHP - Get key name of array value
...rray_search() like this:
$arr = array ('first' => 'a', 'second' => 'b', );
$key = array_search ('a', $arr);
$key will now contain the key for value 'a' (that is, 'first').
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How to change the type of a field?
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In this case, it looks like you're trying to change the $type from 1 (double) to 2 (string).
So simply load the document from the DB, perform the cast (new String(x)) and then save the document again.
If you need to do this programmatically and entirely from the shell, you can use the find(...)....
Pandas: create two new columns in a dataframe with values calculated from a pre-existing column
I am working with the pandas library and I want to add two new columns to a dataframe df with n columns (n > 0).
These new columns result from the application of a function to one of the columns in the dataframe.
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Convert RGBA PNG to RGB with PIL
...transparent PNG image uploaded with Django to a JPG file. The output looks broken.
7 Answers
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Why do we need C Unions?
When should unions be used? Why do we need them?
18 Answers
18
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Equivalent of jQuery .hide() to set visibility: hidden
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You could make your own plugins.
jQuery.fn.visible = function() {
return this.css('visibility', 'visible');
};
jQuery.fn.invisible = function() {
return this.css('visibility', 'hidden');
};
jQuery.fn.visibilityToggle = function() {
return this.css('visibilit...
What is “entropy and information gain”?
I am reading this book ( NLTK ) and it is confusing. Entropy is defined as :
7 Answers
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How to remove unused imports in Intellij IDEA on commit?
...When you commit, tick the Optimize imports option on the right. This will become the default until you change it.
I prefer using the Reformat code option as well.
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How to make a cross-module variable?
The __debug__ variable is handy in part because it affects every module. If I want to create another variable that works the same way, how would I do it?
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How to get unique values in an array
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Since I went on about it in the comments for @Rocket's answer, I may as well provide an example that uses no libraries. This requires two new prototype functions, contains and unique
Array.prototype.contains = function(v) {
for (var i...