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Convert columns to string in Pandas
... your keys to strings):
In [11]: df = pd.DataFrame([['A', 2], ['A', 4], ['B', 6]])
In [12]: df.to_json()
Out[12]: '{"0":{"0":"A","1":"A","2":"B"},"1":{"0":2,"1":4,"2":6}}'
In [13]: df[0].to_json()
Out[13]: '{"0":"A","1":"A","2":"B"}'
Note: you can pass in a buffer/file to save this to, along wi...
How to get the first non-null value in Java?
...at is, is there any way to return the first non-null value of several variables?
12 Answers
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CSS '>' selector; what is it? [duplicate]
I've seen the "greater than" ( > ) used in CSS code a few times, but I can't work out what it does. What does it do?
7 A...
How to iterate through two lists in parallel?
I have two iterables in Python, and I want to go over them in pairs:
8 Answers
8
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Javascript array search and remove string?
...pdating this thread with a more recent 1-line solution:
let arr = ['A', 'B', 'C'];
arr = arr.filter(e => e !== 'B'); // will return ['A', 'C']
The idea is basically to filter the array by selecting all elements different to the element you want to remove.
Note: will remove all occurrences. ...
Why Would I Ever Need to Use C# Nested Classes [duplicate]
I'm trying to understand about nested classes in C#. I understand that a nested class is a class that is defined within another class, what I don't get is why I would ever need to do this.
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What is the difference between a string and a byte string?
I am working with a library which returns a byte string and I need to convert this to a string.
7 Answers
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I want to get the type of a variable at runtime
I want to get the type of a variable at runtime.
How do I do this?
4 Answers
4
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Swapping two variable value without using third variable
... y have different memory locations (rather than different values). This is because (p xor p) = 0 and if both x and y share the same memory location, when one is set to 0, both are set to 0.
When both *x and *y are 0, all other xor operations on *x and *y will equal 0 (as they are the same), which me...
Sort array by firstname (alphabetically) in Javascript
I got an array (see below for one object in the array) that I need to sort by firstname using JavaScript.
How can I do it?
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