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Delete rows from a pandas DataFrame based on a conditional expression involving len(string) giving K
I have a pandas DataFrame and I want to delete rows from it where the length of the string in a particular column is greater than 2.
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Double vs. BigDecimal?
I have to calculate some floating point variables and my colleague suggest me to use BigDecimal instead of double since it will be more precise. But I want to know what it is and how to make most out of BigDecimal ?
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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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What's the point of malloc(0)?
I just saw this code:
17 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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Why is it slower to iterate over a small string than a small list?
I was playing around with timeit and noticed that doing a simple list comprehension over a small string took longer than doing the same operation on a list of small single character strings. Any explanation? It's almost 1.35 times as much time.
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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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RegEx to parse or validate Base64 data
Is it possible to use a RegEx to validate, or sanitize Base64 data? That's the simple question, but the factors that drive this question are what make it difficult.
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I do not want to inherit the child opacity from the parent in CSS
I do not want to inherit the child opacity from the parent in CSS.
14 Answers
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Applying a function to every row of a table using dplyr?
When working with plyr I often found it useful to use adply for scalar functions that I have to apply to each and every row.
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