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How to calculate cumulative normal distribution?
...tion here.
That is, since Python 2.7, the math library has integrated the error function math.erf(x)
The erf() function can be used to compute traditional statistical functions such as the cumulative standard normal distribution:
from math import *
def phi(x):
#'Cumulative distribution functi...
Get records with max value for each group of grouped SQL results
...a mysql-only solution. All other databases I know will throw an SQL syntax error with the message "non aggregated columns are not listed in the group by clause" or similar. Because this solution uses undocumented behavior, the more cautious may want to include a test to assert that it remains workin...
How do you add an in-app purchase to an iOS application?
...called when the transaction does not finish
if(transaction.error.code == SKErrorPaymentCancelled){
NSLog(@"Transaction state -> Cancelled");
//the user cancelled the payment ;(
}
[[SKPaymentQueue defaultQueue]...
Is there a performance difference between a for loop and a for-each loop?
...oduced in
release 1.5, gets rid of the clutter
and the opportunity for error by
hiding the iterator or index variable
completely. The resulting idiom
applies equally to collections and
arrays:
// The preferred idiom for iterating over collections and arrays
for (Element e : elements) {
...
Retrieving the output of subprocess.call() [duplicate]
...G\|NEF\|jpg\)" '
#cmd = raw_input("shell:")
args = shlex.split(cmd)
output,error = subprocess.Popen(args,stdout = subprocess.PIPE, stderr= subprocess.PIPE).communicate()
#Another way to get output
#output = subprocess.Popen(args,stdout = subprocess.PIPE).stdout
ber = raw_input("search complete, disp...
How can I install pip on Windows?
...'t have a C/C++ compiler installed and configured, you'll see this cryptic error message.
Error: Unable to find vcvarsall.bat
You can fix that by installing a C++ compiler such as MinGW or Visual C++. Microsoft actually ships one specifically for use with Python. Or try Microsoft Visual C++ Co...
Remove an element from a Bash array
...te
local aryref="$2[@]" # a necessary step since '${!$2[@]}' is a syntax error
local arycopy=("${!aryref}") # create a copy of the input array
local status=1
for (( i = ${#arycopy[@]} - 1; i >= 0; i-- )); do # iterate over indices backwards
elmt=${arycopy[$i]}
[[ $elmt == $word ]]...
How to add a second css class with a conditional value in razor MVC 4
...
The 2nd option causes the error The "div" element was not closed
– intrepidis
Apr 15 '15 at 14:55
6
...
Why does sudo change the PATH?
.../local/bin"
but when I do that in Ubuntu 8.10 at least, it gives me this error:
visudo: unknown defaults entry `secure_path' referenced near line 10
Ubuntu bug #50797 ("sudo built with --with-secure-path is problematic")
Worse still, as far as I can tell, it
is impossible to respecify s...
back button callback in navigationController in iOS
...o UINavigationBarDelegate, trying to call it will result in a compile time error. The solution I went with is to use Objective-C runtime to get the implementation directly and call it. Please let me know if anyone has a better solution.
The other problem is that navigationBar(_:shouldPop:) is calle...