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How to get device make and model on iOS?
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19 Answers
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Can you break from a Groovy “each” closure?
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194
Nope, you can't abort an "each" without throwing an exception. You likely want a classic loop...
Rename specific column(s) in pandas
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edited May 23 '17 at 12:34
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answered Nov 3 '13 at 21:32
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Performance of foreach, array_map with lambda and array_map with static function
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122
FWIW, I just did the benchmark since poster didn't do it. Running on PHP 5.3.10 + XDebug.
UP...
How do I interpret precision and scale of a number in a database?
...efers to the maximum number of digits that are present in the number.
ie 1234567.89 has a precision of 9
Numeric scale refers to the maximum number of decimal places
ie 123456.789 has a scale of 3
Thus the maximum allowed value for decimal(5,2) is 999.99
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GridLayout and Row/Column Span Woe
...oid:layout_gravity="fill"
android:layout_rowSpan="2"
android:text="1" />
<Button
android:layout_columnSpan="2"
android:layout_gravity="fill_horizontal"
android:text="2" />
<Button
android:layout_gravity="fill_vertical"
android:layout_rowSpan="4"
android:...
Aggregate / summarize multiple variables per group (e.g. sum, mean)
...he reshape2 package for this task:
require(reshape2)
df_melt <- melt(df1, id = c("date", "year", "month"))
dcast(df_melt, year + month ~ variable, sum)
# year month x1 x2
1 2000 1 -80.83405 -224.9540159
2 2000 2 -223.76331 -288.2418017
3 2000 3 -188.83930 -481....
mongodb group values by multiple fields
...dr",
"book": "$book"
},
"bookCount": { "$sum": 1 }
}},
{ "$group": {
"_id": "$_id.addr",
"books": {
"$push": {
"book": "$_id.book",
"count": "$bookCount"
},
},
"count": { "$s...
Numpy index slice without losing dimension information
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It's probably easiest to do x[None, 10, :] or equivalently (but more readable) x[np.newaxis, 10, :].
As far as why it's not the default, personally, I find that constantly having arrays with singleton dimensions gets annoying very quickly. I'd guess the nump...
What is the difference between Lisp-1 and Lisp-2?
I have tried to understand the difference between Lisp-1 and Lisp-2 and how this relates to Clojure but I still do not understand properly. Can anyone enlighten me?
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