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How can we match a^n b^n with Java regex?
...tion (?=…).
Here is our pattern with a simple test harness:
function testAll($r, $tests) {
foreach ($tests as $test) {
$isMatch = preg_match($r, $test, $groups);
$groupsJoined = join('|', $groups);
print("$test $isMatch $groupsJoined\n");
}
}
$tests = array('aaa', 'aaab',...
Arduino Sketch upload issue - avrdude: stk500_recv(): programmer is not responding
...it works. I figured the packets were some attempt at a hand-shake. So basically, I solved it using Google, patience and futzing around with the board!
– hoipolloi
Jan 12 '14 at 18:16
...
Is there a ceiling equivalent of // operator in Python?
...t shy of an order of magnitude faster than forcing the float division and calling ceil(), provided you care about the speed. Which you shouldn't, unless you've proven through usage that you need to.
>>> timeit.timeit("((5 - 1) // 4) + 1", number = 100000000)
1.7249219375662506
>>>...
How to apply a function to two columns of Pandas dataframe
Suppose I have a df which has columns of 'ID', 'col_1', 'col_2' . And I define a function :
12 Answers
...
How do I check if a variable exists?
...have nested functions, variables in outer scopes. If you want to check for all of them, you're probably best off triggering NameError after all.
– Petr Viktorin
Jun 10 '14 at 20:18
...
Check if a value is within a range of numbers
...u're asking a question about numeric comparisons, so regular expressions really have nothing to do with the issue. You don't need "multiple if" statements to do it, either:
if (x >= 0.001 && x <= 0.009) {
// something
}
You could write yourself a "between()" function:
function b...
python list in sql query as parameter
... performed the same query. Doing this I got the erroy i.e. Type Error: not all arguments converted during string formatting. How am I supposed to solbe it
– TechJhola
Jan 9 '15 at 19:55
...
/bin/sh: pushd: not found
...d by child processes. (A hypothetical pushd command might do the chdir(2) call and then start a new shell, but ... it wouldn't be very usable.) pushd is a shell builtin, just like cd.
So, either change your script to start with #!/bin/bash or store the current working directory in a variable, do yo...
Launching Google Maps Directions via an intent on Android
...
Navigation intents seem to be officially supported now: developers.google.com/maps/documentation/android/…
– Sanketh Katta
Feb 15 '15 at 1:59
...
Difference Between Cohesion and Coupling
... example of low cohesion at the top looks pretty good, I think you accidentally meant to say "high cohession"
– relipse
Mar 4 '16 at 14:45
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