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Can dplyr package be used for conditional mutating?
Can the mutate be used when the mutation is conditional (depending on the values of certain column values)?
5 Answers
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Seeding the random number generator in Javascript
Is it possible to seed the random number generator (Math.random) in Javascript?
13 Answers
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Constructor overload in TypeScript
Has anybody done constructor overloading in TypeScript. On page 64 of the language specification (v 0.8), there are statements describing constructor overloads, but there wasn't any sample code given.
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How to round a number to significant figures in Python
I need to round a float to be displayed in a UI. E.g, to one significant figure:
20 Answers
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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
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Ruby, remove last N characters from a string?
What is the preferred way of removing the last n characters from a string?
13 Answers
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How to calculate the number of occurrence of a given character in each row of a column of strings?
I have a data.frame in which certain variables contain a text string. I wish to count the number of occurrences of a given character in each individual string.
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How do I cast a string to integer and have 0 in case of error in the cast with PostgreSQL?
In PostgreSQL I have a table with a varchar column. The data is supposed to be integers and I need it in integer type in a query. Some values are empty strings.
The following:
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Using bitwise OR 0 to floor a number
A colleague of mine stumbled upon a method to floor float numbers using a bitwise or:
6 Answers
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How to extract numbers from a string and get an array of ints?
I have a String variable (basically an English sentence with an unspecified number of numbers) and I'd like to extract all the numbers into an array of integers. I was wondering whether there was a quick solution with regular expressions?
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