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Replacing blank values (white space) with NaN in pandas
I want to find all values in a Pandas dataframe that contain whitespace (any arbitrary amount) and replace those values with NaNs.
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Show a PDF files in users browser via PHP/Perl
I want to show my users PDF files. The reason why I use cgi to show the pdf is I want to track the clicks for the pdf, and cloak the real location of the saved pdf.
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Scala: what is the best way to append an element to an Array?
Say I have an Array[Int] like
3 Answers
3
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Escaping a forward slash in a regular expression
My question is a simple one, and it is about regular expression escaping. Do you have to escape a forward slash / in a regular expression? And how would you go about doing it?
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UIScrollView scroll to bottom programmatically
How can I make a UIScrollView scroll to the bottom within my code? Or in a more generic way, to any point of a subview?
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What's the best way to set a single pixel in an HTML5 canvas?
The HTML5 Canvas has no method for explicitly setting a single pixel.
14 Answers
14
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How should one use std::optional?
I'm reading the documentation of std::experimental::optional and I have a good idea about what it does, but I don't understand when I should use it or how I should use it. The site doesn't contain any examples as of yet which leaves it harder for me to grasp the true concept of this object. When...
With MySQL, how can I generate a column containing the record index in a table?
Is there any way I can get the actual row number from a query?
8 Answers
8
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Count with IF condition in MySQL query
I have two tables, one is for news and the other one is for comments and I want to get the count of the comments whose status has been set as approved.
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Byte[] to InputStream or OutputStream
I have a blob column in my database table, for which I have to use byte[] in my Java program as a mapping and to use this data I have to convert it to InputStream or OutputStream . But I don't know what happens internally when I do so. Can anyone briefly explain me what's happening when I do th...