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Why isn't my Pandas 'apply' function referencing multiple columns working? [closed]
I have some problems with the Pandas apply function, when using multiple columns with the following dataframe
6 Answers
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Remove rows with all or some NAs (missing values) in data.frame
I'd like to remove the lines in this data frame that:
16 Answers
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MySQL - Rows to Columns
I tried to search posts, but I only found solutions for SQL Server/Access. I need a solution in MySQL (5.X).
12 Answers
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Filter rows which contain a certain string
I have to filter a data frame using as criterion those row in which is contained the string RTB .
4 Answers
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How can I convert a DateTime to the number of seconds since 1970?
I'm trying to convert a C# DateTime variable to Unix time, ie, the number of seconds since Jan 1st, 1970. It looks like a DateTime is actually implemented as the number of 'ticks' since Jan 1st, 0001.
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How can I force division to be floating point? Division keeps rounding down to 0?
I have two integer values a and b , but I need their ratio in floating point. I know that a < b and I want to calculate a / b , so if I use integer division I'll always get 0 with a remainder of a .
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What is a regular expression for a MAC Address?
In this format:
21 Answers
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Boolean Field in Oracle
Yesterday I wanted to add a boolean field to an Oracle table. However, there isn't actually a boolean data type in Oracle. Does anyone here know the best way to simulate a boolean? Googling the subject discovered several approaches
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How to toggle a value in Python
What is the most efficient way to toggle between 0 and 1 ?
17 Answers
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How do you add swap to an EC2 instance?
I'm currently running an ec2 micro instance and i've been finding that the instance occasionally runs out of memory.
10 Ans...