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Does pandas iterrows have performance issues?
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Generally, iterrows should only be used in very, very specific cases. This is the general order of precedence for performance of various operations:
1) vectorization
2) using a custom cython routine
3) apply
a) reductions tha...
How to append a newline to StringBuilder
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@tuscland - Why not just use System.lineSeparator() all the time? Why is '\n' a better option as default?
– RyanfaeScotland
Jun 3 '15 at 15:46
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How do you match only valid roman numerals with a regular expression?
...0,3})$
Breaking it down, M{0,4} specifies the thousands section and basically restrains it to between 0 and 4000. It's a relatively simple:
0: <empty> matched by M{0}
1000: M matched by M{1}
2000: MM matched by M{2}
3000: MMM matched by M{3}
4000: MMMM matched by M...
Setting mime type for excel document
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edited Feb 22 at 1:46
Callum Watkins
2,22222 gold badges2323 silver badges4040 bronze badges
answered Dec 26 '09 at 19:44
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How to sort a HashSet?
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Add all your objects to the TreeSet, you will get a sorted Set. Below is a raw example.
HashSet myHashSet = new HashSet();
myHashSet.add(1);
myHashSet.add(23);
myHashSet.add(45);
myHashSet.add(12);
TreeSet myTreeSet = new TreeS...
Change the name of a key in dictionary
...>>> dictionary['ONE'] = dictionary.pop(1)
Traceback (most recent call last):
File "<input>", line 1, in <module>
KeyError: 1
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Android add placeholder text to EditText
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Thanks! I didn't know what they call it in android, I just know that on iOS it's called placeholder.
– Mona
Nov 22 '11 at 4:24
40
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Remove the last three characters from a string
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read last 3 characters from string [Initially asked question]
You can use string.Substring and give it the starting index and it will get the substring starting from given index till end.
myString.Substring(myString.Length-3)
Retrieves a substring from this...
How do I query between two dates using MySQL?
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Personally, I find the term 'from' and 'to' a sneaky way to remember the order in which the query should be written.
– KeaganFouche
Jan 21 '19 at 22:04
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What's the reason I can't create generic array types in Java?
What's the reason why Java doesn't allow us to do
17 Answers
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