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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...
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...
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...
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...
Problems installing the devtools package
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As per damienfrancois's suggestion, I installed libcurl4-gnutls-dev and the problem was solved.
EDIT (@dardisco)
In your shell:
apt-get -y build-dep libcurl4-gnutls-dev
apt-get -y install libcurl4-gnutls-dev
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How does this program work?
...oint number is converted to double before sending to printf. The number 1234.5 in double representation in little endian is
00 00 00 00 00 4A 93 40
A %d consumes a 32-bit integer, so a zero is printed. (As a test, you could printf("%d, %d\n", 1234.5f); You could get on output 0, 1083394560.)
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'System.Net.Http.HttpContent' does not contain a definition for 'ReadAsAsync' and no extension metho
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141
After a long struggle, I found the solution.
Solution: Add a reference to System.Net.Http.Form...
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...