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How to extract numbers from a string in Python?
...nly positive integers, try the following:
>>> str = "h3110 23 cat 444.4 rabbit 11 2 dog"
>>> [int(s) for s in str.split() if s.isdigit()]
[23, 11, 2]
I would argue that this is better than the regex example because you don't need another module and it's more readable because you d...
How to write loop in a Makefile?
... your use of ./a.out, you're on a UNIX-type platform.
for number in 1 2 3 4 ; do \
./a.out $$number ; \
done
Test as follows:
target:
for number in 1 2 3 4 ; do \
echo $$number ; \
done
produces:
1
2
3
4
For bigger ranges, use:
target:
number=1 ; while [[ $$number -...
How do I switch between the header and implementation file in Xcode 4?
How do I switch between the header and implementation file in Xcode 4?
7 Answers
7
...
Is the size of C “int” 2 bytes or 4 bytes?
Does an Integer variable in C occupy 2 bytes or 4 bytes? What are the factors that it depends on?
13 Answers
...
Intellij shortcut to convert code to upper or lower case?
...
477
Ctrl + Shift + U
In the future try typing: Ctrl + Shift + A and look for any actions you like...
Python Dictionary Comprehension
...;> d = {n: n**2 for n in range(5)}
>>> print d
{0: 0, 1: 1, 2: 4, 3: 9, 4: 16}
If you want to set them all to True:
>>> d = {n: True for n in range(5)}
>>> print d
{0: True, 1: True, 2: True, 3: True, 4: True}
What you seem to be asking for is a way to set multiple...
Why is it slower to iterate over a small string than a small list?
...thon3 -m timeit '[x for x in ["a", "b", "c"]]'
1000000 loops, best of 3: 0.436 usec per loop
This disagrees with what you've found...
You must be using Python 2, then.
>>> python2 -m timeit '[x for x in "abc"]'
1000000 loops, best of 3: 0.309 usec per loop
>>> python2 -m timei...
Pairs from single list
... section.
– Apalala
Jan 7 '11 at 18:40
@Apalala: zip does advance the same iterator twice.
– Joc...
How do you install Google frameworks (Play, Accounts, etc.) on a Genymotion virtual device? [duplica
...(Feb 2nd): Contrary to previous reports, it's been discovered that Android 4.4 does in fact work with ARM translation, although it is buggy. Follow the steps the same as before, just make sure you download the 4.4 GApps.
UPDATE-v1.1: I've gotten more up-to-date builds of libhoudini and have updated ...
Remove rows with all or some NAs (missing values) in data.frame
...cases(final), ]
gene hsap mmul mmus rnor cfam
2 ENSG00000199674 0 2 2 2 2
6 ENSG00000221312 0 1 2 3 2
na.omit is nicer for just removing all NA's. complete.cases allows partial selection by including only certain columns of the dataframe:
> final[comp...