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Formula to determine brightness of RGB color
I'm looking for some kind of formula or algorithm to determine the brightness of a color given the RGB values. I know it can't be as simple as adding the RGB values together and having higher sums be brighter, but I'm kind of at a loss as to where to start.
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How to convert index of a pandas dataframe into a column?
This seems rather obvious, but I can't seem to figure out how to convert an index of data frame to a column?
7 Answers
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How can I check if a string represents an int, without using try/except?
Is there any way to tell whether a string represents an integer (e.g., '3' , '-17' but not '3.14' or 'asfasfas' ) Without using a try/except mechanism?
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Multiple linear regression in Python
I can't seem to find any python libraries that do multiple regression. The only things I find only do simple regression. I need to regress my dependent variable (y) against several independent variables (x1, x2, x3, etc.).
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Pandas index column title or name
How do I get the index column name in python pandas? Here's an example dataframe:
9 Answers
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How to select rows with one or more nulls from a pandas DataFrame without listing columns explicitly
I have a dataframe with ~300K rows and ~40 columns.
I want to find out if any rows contain null values - and put these 'null'-rows into a separate dataframe so that I could explore them easily.
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Simplest way to profile a PHP script
What's the easiest way to profile a PHP script?
13 Answers
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Should I return EXIT_SUCCESS or 0 from main()?
It's a simple question, but I keep seeing conflicting answers: should the main routine of a C++ program return 0 or EXIT_SUCCESS ?
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How do I check to see if a value is an integer in MySQL?
I see that within MySQL there are Cast() and Convert() functions to create integers from values, but is there any way to check to see if a value is an integer? Something like is_int() in PHP is what I am looking for.
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Why `null >= 0 && null
I had to write a routine that increments the value of a variable by 1 if its type is number and assigns 0 to the variable if not, where the variable is initially null or undefined .
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