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Index all *except* one item in python
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For a list, you could use a list comp. For example, to make b a copy of a without the 3rd element:
a = range(10)[::-1] # [9, 8, 7, 6, 5, 4, 3, 2, 1, 0]
b = [x for i,x in enumerate(a) if i!=3] # [9, 8, 7, 5, 4, 3, 2, 1, 0]
This is very general, and can be use...
Detect Browser Language in PHP
I use the following PHP script as index for my website.
12 Answers
12
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shortcut for creating a Map from a List in groovy?
...to do exactly that: converting a list into a map. This question was posted before Groovy version 1.7.9 came out, so the method collectEntries didn't exist yet. It works exactly as the collectMap method that was proposed:
Map rowToMap(row) {
row.columns.collectEntries{[it.name, it.val]}
}
If f...
What's valid and what's not in a URI query?
I've been Googling this back and forth reading RFCs and SO questions trying to crack this, but I still don't got jack.
7 An...
What is the difference between join and merge in Pandas?
...join on indices:
import pandas as pd
left = pd.DataFrame({'key': ['foo', 'bar'], 'val': [1, 2]}).set_index('key')
right = pd.DataFrame({'key': ['foo', 'bar'], 'val': [4, 5]}).set_index('key')
left.join(right, lsuffix='_l', rsuffix='_r')
val_l val_r
key
foo 1 4
bar ...
How do I sort unicode strings alphabetically in Python?
Python sorts by byte value by default, which means é comes after z and other equally funny things. What is the best way to sort alphabetically in Python?
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Why aren't ◎ܫ◎ and ☺ valid JavaScript variable names?
I noticed that in Internet Explorer (but, unfortunately, not in the other browsers I tested), you can use some Unicode variable names. This made my day, and I was absolutely delighted that I could write fun Unicode-laden code like this:
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Way to go from recursion to iteration
...d recursion quite a lot on my many years of programming to solve simple problems, but I'm fully aware that sometimes you need iteration due to memory/speed problems.
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Maximum number of characters using keystrokes A, Ctrl+A, Ctrl+C and Ctrl+V
This is an interview question from google. I am not able to solve it by myself. Can somebody shed some light?
14 Answers
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Why are arrays of references illegal?
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Answering to your question about standard I can cite the C++ Standard §8.3.2/4:
There shall be no references to references, no arrays of references, and no pointers to references.
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