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Strings in a DataFrame, but dtype is object
...mly requested element. The key to overcoming this is to use pointers. Basically, store each string in some random memory location, and fill the array with the memory address of each string. (Memory addresses are just integers.) So now, things look like this
Now, if you ask your computer to fetch th...
Howto: Clean a mysql InnoDB storage engine?
...lib/mysql/ibdata1 is the busiest file in the InnoDB infrastructure. It normally houses six types of information:
Table Data
Table Indexes
MVCC (Multiversioning Concurrency Control) Data
Rollback Segments
Undo Space
Table Metadata (Data Dictionary)
Double Write Buffer (background writing to prev...
How to perform element-wise multiplication of two lists?
I want to perform an element wise multiplication, to multiply two lists together by value in Python, like we can do it in Matlab.
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initialize a numpy array
...nd add to it? I will explain what I need with a list example. If I want to create a list of objects generated in a loop, I can do:
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Simple way to calculate median with MySQL
...ime finding a simple way of calculating the median. For now, I'm returning all the rows to PHP, doing a sort, and then picking the middle row, but surely there must be some simple way of doing it in a single MySQL query.
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Is there a float input type in HTML5?
...>
(I'd also set min=0 if it can only be positive)
If you'd prefer to allow any number of decimal places, you can use step="any" (though for currencies, I'd recommend sticking to 0.01). In Chrome & Firefox, the stepper buttons will increment / decrement by 1 when using any. (thanks to Micha...
Is the ternary operator faster than an “if” condition in Java [duplicate]
...one to " if-conditional syndrome " which means I tend to use if conditions all the time. I rarely ever use the ternary operator. For instance:
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How to understand nil vs. empty vs. blank in Ruby
...s the negation of .blank?.
Array gotcha: blank? will return false even if all elements of an array are blank. To determine blankness in this case, use all? with blank?, for example:
[ nil, '' ].blank? == false
[ nil, '' ].all? &:blank? == true
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What can I use for good quality code coverage for C#/.NET? [closed]
I wonder what options there are for .NET (or C# specifically) code coverage, especially in the lower priced segment?
12 Ans...