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Does SQLAlchemy have an equivalent of Django's get_or_create?
...t Django's implementation of get_or_create. It checks for integrity error, and relies upon proper use of unique constraints.
– Ivan Virabyan
May 21 '12 at 6:17
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Regex to match only letters
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Use a character set: [a-zA-Z] matches one letter from A–Z in lowercase and uppercase. [a-zA-Z]+ matches one or more letters and ^[a-zA-Z]+$ matches only strings that consist of one or more letters only (^ and $ mark the begin and end of a string respectively).
If you want to match other letters...
Read an Excel file directly from a R script
... directly into R? Or should I first export the data to a text- or CSV file and import that file into R?
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Should commit messages be written in present or past tense? [closed]
So which is it that you think is better and more intuitive?
12 Answers
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What are the Ruby Gotchas a newbie should be warned about? [closed]
I have recently learned the Ruby programming language, and all in all it is a good language. But I was quite surprised to see that it was not as simple as I had expected. More precisely, the "rule of least-surprise" did not seem very respected to me (of course this is quite subjective). For examp...
How do I capture response of form.submit
...n javascript. When you post a form, the form inputs are sent to the server and your page is refreshed - the data is handled on the server side. That is, the submit() function doesn't actually return anything, it just sends the form data to the server.
If you really wanted to get the response in Jav...
Getter and Setter declaration in .NET [duplicate]
...s wondering what were the differences between those declaration of getters and setters and if there is a preferred method (and why). The first one can be generated automaticly by Visual Studio. How about the others ? Thanks
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What is a faster alternative to Python's http.server (or SimpleHTTPServer)?
...is a great way of serve the contents of the current directory from the command line:
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vs
... HTML5, they are equivalent. Use the shorter one, it is easier to remember and type. Browser support is fine since it was designed for backwards compatibility.
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Find the max of two or more columns with pandas
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You can get the maximum like this:
>>> import pandas as pd
>>> df = pd.DataFrame({"A": [1,2,3], "B": [-2, 8, 1]})
>>> df
A B
0 1 -2
1 2 8
2 3 1
>>> df[["A", "B"]]
A B
0 1 -2
1 2 8
2 3 1
>>> df[["A", "B"]].max(axis=1)
0...