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Lost my schema.rb! Can it be regenerated?
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edited Jan 7 '16 at 15:40
answered Mar 16 '12 at 3:52
mg...
Numbering rows within groups in a data frame
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284
Use ave, ddply, dplyr or data.table:
df$num <- ave(df$val, df$cat, FUN = seq_along)
or:
l...
VIM + JSLint?
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34
You can follow the intructions from JSLint web-service + VIM integration or do what I did:
Down...
Java: Get first item from a collection
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ISanych
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answered Nov 4 '09 at 3:09
CarlCarl
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jekyll markdown internal links
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254
You can now post internal links by using the following:
[Some Link]({% post_url 2010-07-21-name...
Best practice for nested fragments in Android 4.0, 4.1 (
I'm writing an app for 4.0 and 4.1 tablets, for which I do not want to use the support libraries (if not needed) but the 4.x api only therefore.
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How to permanently export a variable in Linux?
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answered Oct 24 '12 at 9:45
AntoineAntoine
10.5k44 gold badges3131 silver badges4646 bronze badges
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Removing duplicates from a list of lists
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>>> k = [[1, 2], [4], [5, 6, 2], [1, 2], [3], [4]]
>>> import itertools
>>> k.sort()
>>> list(k for k,_ in itertools.groupby(k))
[[1, 2], [3], [4], [5, 6, 2]]
itertools often offers the fastest and most powerful so...
Compare double to zero using epsilon
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194
Assuming 64-bit IEEE double, there is a 52-bit mantissa and 11-bit exponent. Let's break it to b...
A CORS POST request works from plain JavaScript, but why not with jQuery?
...name, password, or cookies, etc), read on.
I think I found the answer! (4 hours and a lot of cursing later)
//This does not work!!
Access-Control-Allow-Headers: *
You need to manually specify all the headers you will accept (at least that was the case for me in FF 4.0 & Chrome 10.0.648.204...