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Appending an element to the end of a list in Scala
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List(1,2,3) :+ 4
Results in List[Int] = List(1, 2, 3, 4)
Note that this operation has a complexity of O(n). If you need this operation frequently, or for long lists, consider using another data type (e.g. a ListBuffer).
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Matplotlib: “Unknown projection '3d'” error
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edited Apr 4 '19 at 18:23
Matthew Salvatore Viglione
4,14911 gold badge1010 silver badges3333 bronze badges
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Python argparse: default value or specified value
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286
import argparse
parser = argparse.ArgumentParser()
parser.add_argument('--example', nargs='?',...
Best way to make Java's modulus behave like it should with negative numbers?
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Maarten Bodewes
76.4k1212 gold badges114114 silver badges213213 bronze badges
answered Dec 10 '10 at 18:46
Peter LawreyPete...
How to loop through all but the last item of a list?
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324
for x in y[:-1]
If y is a generator, then the above will not work.
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What is the difference between Ruby 1.8 and Ruby 1.9
..."cat"[1]
=> 97
{"a","b"} No Longer Supported
Ruby 1.9
irb(main):002:0> {1,2}
SyntaxError: (irb):2: syntax error, unexpected ',', expecting tASSOC
Ruby 1.8.6
irb(main):001:0> {1,2}
=> {1=>2}
Action: Convert to {1 => 2}
Array.to_s Now Contains Punctuation
Ruby 1.9
irb...
Getting the count of unique values in a column in bash
... see a frequency count for column two (for example):
awk -F '\t' '{print $2}' * | sort | uniq -c | sort -nr
fileA.txt
z z a
a b c
w d e
fileB.txt
t r e
z d a
a g c
fileC.txt
z r a
v d c
a m c
Result:
3 d
2 r
1 z
1 m
1 g
1...
How can I make pandas dataframe column headers all lowercase?
...e(3,0,-1), 'C':list('abc')})
>>> data
A B C
0 0 3 a
1 1 2 b
2 2 1 c
>>> data.columns = map(str.lower, data.columns)
>>> data
a b c
0 0 3 a
1 1 2 b
2 2 1 c
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How to change a command line argument in Bash?
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2 Answers
2
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How to define different dependencies for different product flavors
... }
dependencies {
classpath 'com.android.tools.build:gradle:1.2.3'
}
}
apply plugin: 'com.android.application'
repositories {
mavenCentral()
}
android {
compileSdkVersion 22
buildToolsVersion "22.0.1"
defaultConfig {
minSdkVersion 10
targetSdkVersi...