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All falsey values in JavaScript
What are the values in JavaScript that are 'falsey' , meaning that they evaluate as false in expressions like if(value) , value ? and !value ?
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Javascript calculate the day of the year (1 - 366)
How do I use javascript to calculate the day of the year, from 1 - 366? For example:
22 Answers
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How to initialize a two-dimensional array in Python?
I'm beginning python and I'm trying to use a two-dimensional list, that I initially fill up with the same variable in every place. I came up with this:
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How do I print a double value without scientific notation using Java?
I want to print a double value in Java without exponential form.
14 Answers
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Converting RGB to grayscale/intensity
When converting from RGB to grayscale, it is said that specific weights to channels R, G, and B ought to be applied. These weights are: 0.2989, 0.5870, 0.1140.
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How to find the kth smallest element in the union of two sorted arrays?
This is a homework question. They say it takes O(logN + logM) where N and M are the arrays lengths.
17 Answers
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How do you rotate a two dimensional array?
Inspired by Raymond Chen's post , say you have a 4x4 two dimensional array, write a function that rotates it 90 degrees. Raymond links to a solution in pseudo code, but I'd like to see some real world stuff.
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Replace all 0 values to NA
I have a dataframe with some numeric columns. Some row has a 0 value which should be considered as null in statistical analysis. What is the fastest way to replace all the 0 value to NULL in R?
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Why is a round-trip conversion via a string not safe for a double?
Recently I have had to serialize a double into text, and then get it back. The value seems to not be equivalent:
3 Answers
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Gray out image with CSS?
What's the best way (if any) to make an image appear "grayed out" with CSS (i.e., without loading a separate, grayed out version of the image)?
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