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I'm getting Key error in python
... +1 for very relevant .get() comment. Looks like a good application of the Python EAFP (Easier to Ask for Forgiveness than Permission) instead of LBYL (Look Before You Leap) which I think is less Pythonic.
– Niels Bom
Apr 24 '12 at 11:08
...
Mean per group in a data.frame [duplicate]
...53 19
Ben 2 22 87
Ben 3 19 45
Cat 1 22 87
Cat 2 67 43
Cat 3 45 32', header=TRUE)
aggregate(d[, 3:4], list(d$Name), mean)
Group.1 Rate1 Rate2
1 Aira 16.33333 47.00000
2 Ben 31.33333 ...
How do I read the first line of a file using cat?
How do I read the first line of a file using cat ?
10 Answers
10
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Finding all objects that have a given property inside a collection [duplicate]
I have some complicated object, such as a Cat, which has many properties, such as age, favorite cat food, and so forth.
2...
Why is reading lines from stdin much slower in C++ than Python?
...wered Feb 21 '12 at 3:24
Vaughn CatoVaughn Cato
58.3k55 gold badges7171 silver badges111111 bronze badges
...
Can linux cat command be used for writing text to file?
...
Sounds like you're looking for a Here document
cat > outfile.txt <<EOF
>some text
>to save
>EOF
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f...
How does “cat
...b character. If you do it right, your syntax highlighting should correctly catch the ending delimiter.
– trkoch
Nov 10 '15 at 17:23
1
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Implements vs extends: When to use? What's the difference?
... void main(String args[]){
Dog dog = new Dog("Tiger",16);
Cat cat = new Cat("July",20);
System.out.println("Dog:"+dog);
System.out.println("Cat:"+cat);
dog.remember();
dog.protectOwner();
Learn dl = dog;
dl.learn();
cat.reme...
How to cat a file containing code?
I want to print code into a file using cat <<EOF >> :
4 Answers
4
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What is the function __construct used for?
...o declare the constructor. You can also use the class name, for ex:
class Cat
{
function Cat()
{
echo 'meow';
}
}
and
class Cat
{
function __construct()
{
echo 'meow';
}
}
Are equivalent. They are called whenever a new instance of the class is created, i...