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What is the ultimate postal code and zip regex?
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132
There is none.
Postal/zip codes around the world don't follow a common pattern. In some countr...
How can I delete one element from an array by value
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I think I've figured it out:
a = [3, 2, 4, 6, 3, 8]
a.delete(3)
#=> 3
a
#=> [2, 4, 6, 8]
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How can I sort a dictionary by key?
What would be a nice way to go from {2:3, 1:89, 4:5, 3:0} to {1:89, 2:3, 3:0, 4:5} ?
I checked some posts but they all use the "sorted" operator that returns tuples.
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For each row return the column name of the largest value
...amples using sample reproducible):
DF <- data.frame(V1=c(2,8,1),V2=c(7,3,5),V3=c(9,6,4))
colnames(DF)[apply(DF,1,which.max)]
[1] "V3" "V1" "V2"
A faster solution than using apply might be max.col:
colnames(DF)[max.col(DF,ties.method="first")]
#[1] "V3" "V1" "V2"
...where ties.method can be...
How do you match only valid roman numerals with a regular expression?
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330
You can use the following regex for this:
^M{0,4}(CM|CD|D?C{0,3})(XC|XL|L?X{0,3})(IX|IV|V?I{0...
Does assignment with a comma work?
Why does aaa = 1,2,3 work and set the value of aaa to 1 ?
4 Answers
4
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Version of SQLite used in Android?
...database.sqlite package-level javadoc
Using the emulators:
adb shell sqlite3 --version
UPDATE: Since SDK 29 (emulator revision 8), the adb shell command gives:
/system/bin/sh: sqlite3: inaccessible or not found
Any ideas why? Issue tracker here.
SQLite 3.28.0 (window functions!):
30-11.0-R (Re...
Reshape three column data frame to matrix (“long” to “wide” format) [duplicate]
...similar questions scattered around this site.
tmp <- data.frame(x=gl(2,3, labels=letters[24:25]),
y=gl(3,1,6, labels=letters[1:3]),
z=c(1,2,3,3,3,2))
Using the tidyverse:
The new cool new way to do this is with pivot_wider from tidyr 1.0.0. It returns a d...
How do I make a list of data frames?
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135
This isn't related to your question, but you want to use = and not <- within the function ca...
What does axis in pandas mean?
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399
It specifies the axis along which the means are computed. By default axis=0. This is consisten...