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Convert int to ASCII and back in Python

I'm working on making a URL shortener for my site, and my current plan (I'm open to suggestions) is to use a node ID to generate the shortened URL. So, in theory, node 26 might be short.com/z , node 1 might be short.com/a , node 52 might be short.com/Z , and node 104 might be short.com/ZZ . When...
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What is the correct syntax for 'else if'?

... python "else if" is spelled "elif". Also, you need a colon after the elif and the else. Simple answer to a simple question. I had the same problem, when I first started (in the last couple of weeks). So your code should read: def function(a): if a == '1': print('1a') elif a == '2...
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MySQL INNER JOIN select only one row from second table

I have a users table and a payments table, for each user, those of which have payments, may have multiple associated payments in the payments table. I would like to select all users who have payments, but only select their latest payment. I'm trying this SQL but i've never tried nested SQL sta...
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Difference between EXISTS and IN in SQL?

What is the difference between the EXISTS and IN clause in SQL? 21 Answers 21 ...
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MySQL JOIN the most recent row only?

I have a table customer that stores a customer_id, email and reference. There is an additional table customer_data that stores a historical record of the changes made to the customer, i.e. when there's a change made a new row is inserted. ...
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Return multiple columns from pandas apply()

I have a pandas DataFrame, df_test . It contains a column 'size' which represents size in bytes. I've calculated KB, MB, and GB using the following code: ...
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When exactly are onSaveInstanceState() and onRestoreInstanceState() called?

...igure (from the official doc ) describes the well-known lifecycle of an Android activity: 5 Answers ...
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Summarizing multiple columns with dplyr? [duplicate]

... a bit with the dplyr-syntax. I have a data frame with different variables and one grouping variable. Now I want to calculate the mean for each column within each group, using dplyr in R. ...
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Complex nesting of partials and templates

...e... I use nested directive controls. This allows you to set up templating and inherit (or isolate) scopes among them. Outside of that I use ng-switch or even just ng-show to choose which controls I'm displaying based on what's coming in from $routeParams. EDIT Here's some example pseudo-code to gi...
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Argument list too long error for rm, cp, mv commands

... The reason this occurs is because bash actually expands the asterisk to every matching file, producing a very long command line. Try this: find . -name "*.pdf" -print0 | xargs -0 rm Warning: this is a recursive search and will find (and delete) files in subdirectories as ...