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How to convert a data frame column to numeric type?
... that you should apply transform function in order to complete your task.
Now I'm about to demonstrate certain "conversion anomaly":
# create dummy data.frame
d <- data.frame(char = letters[1:5],
fake_char = as.character(1:5),
fac = factor(1:5),
...
Difference between reduce and foldLeft/fold in functional programming (particularly Scala and Scala
...rList.foldLeft(0)(_ + _))
Took 2589.363031 milli seconds
reduce vs fold
Now this is where it gets a little closer to the FP / mathematical roots, and a little trickier to explain. Reduce is defined formally as part of the MapReduce paradigm, which deals with orderless collections (multisets), Fo...
Android: Want to set custom fonts for whole application not runtime
...text, attrs, defStyle);
parseAttributes(context, attrs);
}
}
Now, if you don't have one, add an XML document under res/values/attrs.xml, and add:
<resources>
<!-- Define the values for the attribute -->
<attr name="typeface" format="enum">
<enum na...
How is “int* ptr = int()” value initialization not illegal?
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@NeilG: This stays the same in C++11, though there is now also a nullptr, which you can use instead of 0 or NULL in new code.
– Jerry Coffin
Nov 9 '11 at 23:02
...
Parse usable Street Address, City, State, Zip from a string [closed]
...cademic to write it, there's no weirdness, just lots of string handling.
(Now that you've posted some sample data, I've made some minor changes)
Work backward. Start from the zip code, which will be near the end, and in one of two known formats: XXXXX or XXXXX-XXXX. If this doesn't appear, you ca...
What does @synchronized() do as a singleton method in objective C?
I just created a singleton method, and I would like to know what the function @synchronized() does, as I use it frequently, but do not know the meaning.
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How to check whether a pandas DataFrame is empty?
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This seems like a shame, since you need to know that df is a pd.DataFrame. I'd like to know the motivation for not implementing bool() on pd.DataFrame.
– Quant
Feb 14 '14 at 16:55
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Using CookieContainer with WebClient class
...ed a CookieContainer with HttpWebRequest and HttpWebResponse sessions, but now, I want to use it with a WebClient. As far as I understand, there is no built-in method like there is for HttpWebRequests ( request.CookieContainer ). How can I collect cookies from a WebClient in a CookieContainer?
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Why is my git repository so big?
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wow. THANK YOU. .git = 15M now!! after cloning, here is a little 1 liner for preserving your previous branches. d1=#original repo; d2=#new repo; cd $d1; for b in $(git branch | cut -c 3-); do git checkout $b; x=$(git rev-parse HEAD); cd $d2; git checko...
How to get just the responsive grid from Bootstrap 3?
... was 200px, but the inside was 180px so you had to set the width to 180px, now you set the width to 200px or just nothing and stick it in a grid column class.
– Christina
Dec 6 '13 at 21:49
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