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Usage of sys.stdout.flush() method
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answered Apr 4 '12 at 21:35
Haldean BrownHaldean Brown
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What are '$$' used for in PL/pgSQL
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answered Aug 29 '12 at 6:54
Erwin BrandstetterErwin Brandstetter
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Shading a kernel density plot between two points.
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edited May 1 '17 at 10:34
JD Long
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answered...
git add . vs git commit -a
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140
git commit -a means almost[*] the same thing as git add -u && git commit.
It's not the...
Python OpenCV2 (cv2) wrapper to get image size?
...ls.
– Tomasz Gandor
Jan 9 '15 at 23:46
1
I found this helpful: docs.opencv.org/3.0-beta/doc/py_tu...
John Carmack's Unusual Fast Inverse Square Root (Quake III)
...Quake III source code which calculates the inverse square root of a float, 4x faster than regular (float)(1.0/sqrt(x)) , including a strange 0x5f3759df constant. See the code below. Can someone explain line by line what exactly is going on here and why this works so much faster than the regular i...
What does .SD stand for in data.table in R
...,3), v=1:6)
setkey(DT, y)
DT
# x y v
# 1: a 1 1
# 2: b 1 3
# 3: c 1 5
# 4: a 3 2
# 5: b 3 4
# 6: c 3 6
Doing this may help you see what .SD is:
DT[ , .SD[ , paste(x, v, sep="", collapse="_")], by=y]
# y V1
# 1: 1 a1_b3_c5
# 2: 3 a2_b4_c6
Basically, the by=y statement breaks the orig...
How do I install an old version of Django on virtualenv?
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142
There was never a Django 1.0.7. The 1.0 series only went up to 1.0.4. You can see all the relea...
How to delete object from array inside foreach loop?
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234
foreach($array as $elementKey => $element) {
foreach($element as $valueKey => $value) ...