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Can scrapy be used to scrape dynamic content from websites that are using AJAX?
...and am dipping my hand into building a web-scraper. It's nothing fancy at all; its only purpose is to get the data off of a betting website and have this data put into Excel.
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Renaming columns in pandas
...UMNS
Use the df.rename() function and refer the columns to be renamed. Not all the columns have to be renamed:
df = df.rename(columns={'oldName1': 'newName1', 'oldName2': 'newName2'})
# Or rename the existing DataFrame (rather than creating a copy)
df.rename(columns={'oldName1': 'newName1', 'oldNam...
How does deriving work in Haskell?
Algebraic Data Types (ADTs) in Haskell can automatically become instances of some typeclasse s (like Show , Eq ) by deriving from them.
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How to replace local branch with remote branch entirely in Git?
...contents of master. So if you're on e.g. a feature-branch, it will replace all its commits with master, so make sure you've checked out the branch you're replacing first.
– Zoltán
Jul 15 '16 at 8:29
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How do I get the name of the active user via the command line in OS X?
...if you are ssh'ed into a machine and want to see if a user is logged on locally. If they are not, the command will return "root".
– Tim Dearborn
Jan 15 '16 at 1:17
add a comme...
When should you not use virtual destructors?
...o not declare a virtual destructor for a class? When should you specifically avoid writing one?
12 Answers
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Flask-SQLalchemy update a row's information
...e many objects to be updated.
If you want to give add_user permission to all the admins,
rows_changed = User.query.filter_by(role='admin').update(dict(permission='add_user'))
db.session.commit()
Notice that filter_by takes keyword arguments (use only one =) as opposed to filter which takes an e...
What does the git index contain EXACTLY?
...ns an article on what an index includes:
The index is a binary file (generally kept in .git/index) containing a sorted list of path names, each with permissions and the SHA1 of a blob object; git ls-files can show you the contents of the index:
$ git ls-files --stage
100644 63c918c667fa005ff12ad89...
How to list all the files in a commit?
...ooking for a simple git command that provides a nicely formatted list of all files that were part of the commit given by a hash (SHA1), with no extraneous information.
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Add legend to ggplot2 line plot
...range your data frame
library(reshape2)
dd = melt(dd_sub, id=c("fecha"))
All that's left is a simple ggplot command:
ggplot(dd) + geom_line(aes(x=fecha, y=value, colour=variable)) +
scale_colour_manual(values=c("red","green","blue"))
Example plot
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