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Convert list to tuple in Python
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Expanding on eumiro's comment, normally tuple(l) will convert a list l into a tuple:
In [1]: l = [4,5,6]
In [2]: tuple
Out[2]: <type 'tuple'>
In [3]: tuple(l)
Out[3]: (4, 5, 6)
However, if you've redefined tuple to be...
How to create a colored 1x1 UIImage on the iPhone dynamically?
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You can use CGContextSetFillColorWithColor and CGContextFillRect for this:
Swift
extension UIImage {
class func image(with color: UIColor) -> UIImage {
let rect = CGRectMake(0.0, 0.0, 1.0, 1.0)
UIGraphicsBeginImageContext(rect.size)
le...
Is there a way to specify how many characters of a string to print out using printf()?
...ogous to the "%8.8s" notation, but again allows you to specify the minimum and maximum lengths at runtime - more realistically in a scenario like:
printf("Data: %*.*s Other info: %d\n", minlen, maxlen, string, info);
The POSIX specification for printf() defines these mechanisms.
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What method in the String class returns only the first N characters?
...first str.Length characters of str", but Substring does that check for you and just does return this if you've asked for the whole string.
– stevemegson
Aug 25 '10 at 14:37
2
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Replace non-numeric with empty string
... This is only used a couple of times, so we don't need to create a class, and as far as the leading 1, not a bad idea. But I think I'd rather handle that on a case by case basis, at least in this project. Thanks again -- if I could upvote again, I would.
– Matt Dawdy
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Why isn't my Pandas 'apply' function referencing multiple columns working? [closed]
I have some problems with the Pandas apply function, when using multiple columns with the following dataframe
6 Answers
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Check if a Postgres JSON array contains a string
...ovements on a table of 1,000,000 rabbits where each rabbit likes two foods and 10% of them like carrots:
d=# -- Postgres 9.3 solution
d=# explain analyze select info->>'name' from rabbits where exists (
d(# select 1 from json_array_elements(info->'food') as food
d(# where food::text = '"...
Labels for radio buttons in rails form
...e good one. Caveat: you need Rails >= 2.3.3
– tokland
Dec 10 '10 at 15:27
3
this method also r...
Log to the base 2 in python
....log(x, 2.0)
log2 = math.log2(x) # python 3.4 or later
Thanks @akashchandrakar and @unutbu.
float → int math.frexp(x)
If all you need is the integer part of log base 2 of a floating point number, extracting the exponent is pretty efficient:
log2int_slow = int(math.floor(math.log(x, 2.0)...
How can I change the color of a part of a TextView?
... answered Aug 26 '11 at 17:38
andy bootandy boot
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