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How do I merge two dictionaries in a single expression in Python (taking union of dictionaries)?
I have two Python dictionaries, and I want to write a single expression that returns these two dictionaries, merged (i.e. taking the union). The update() method would be what I need, if it returned its result instead of modifying a dictionary in-place.
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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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What's the right way to pass form element state to sibling/parent elements?
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So, if I'm understanding you correctly, your first solution is suggesting that you're keeping state in your root component? I can't speak for the creators of React, but generally, I find this to be a proper solution.
Maintaining state is one...
Equation (expression) parser with precedence?
...'ve developed an equation parser using a simple stack algorithm that will handle binary (+, -, |, &, *, /, etc) operators, unary (!) operators, and parenthesis.
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diff to output only the file names
I'm looking to run a Linux command that will recursively compare two directories and output only the file names of what is different. This includes anything that is present in one directory and not the other or vice versa, and text differences.
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Pointers in Python?
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I want form.data['field'] and
form.field.value to always have the
same value
This is feasible, because it involves decorated names and indexing -- i.e., completely different constructs from the barenames a and b that you're asking about, and for...
What is the difference between PS1 and PROMPT_COMMAND
...oc page: http://www.gnu.org/software/bash/manual/bashref.html
PROMPT_COMMAND
If set, the value is interpreted as a command to execute before
the printing of each primary prompt ($PS1).
I never used it, but I could have used this back when I only had sh.
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addEventListener vs onclick
What's the difference between addEventListener and onclick ?
16 Answers
16
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Difference between variable declaration syntaxes in Javascript (including global variables)?
...gh in practical terms they're not usually big ones.
There's a fourth way, and as of ES2015 (ES6) there's two more. I've added the fourth way at the end, but inserted the ES2015 ways after #1 (you'll see why), so we have:
var a = 0; // 1
let a = 0; // 1.1 (new with ES2015)
const a = 0; //...
What is the benefit of using Fragments in Android, rather than Views?
When developing for Android , you can set your target (or minimum) sdk to 4 (API 1.6) and add the android compatibility package (v4) to add support for Fragments . Yesterday I did this and successfully implemented Fragments to visualize data from a custom class.
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