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Using JQuery to check if no radio button in a group has been checked
I'm sitting with a problem, I need to check with JQuery if no radio button within a radio button group has been checked, so that I can give the users an javascript error if they forgot to check a option.
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How do I restart nginx only after the configuration test was successful on Ubuntu?
...I know, nginx would show an empty message and it wouldn't actually restart if the configuration is bad.
The only way to screw it up is by doing an nginx stop and then start again. It would succeed to stop, but fail to start.
...
Multiple Updates in MySQL
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If there is no duplicates then i dont want that row to be inserted. what should id do? because i am fetching information from another site which maintains tables with id's. I am inserting values with respect to that id. if th...
Retrieving Android API version programmatically
...o this int is in the android.os.Build.VERSION_CODES class.
Code example:
if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.LOLLIPOP){
// Do something for lollipop and above versions
} else{
// do something for phones running an SDK before lollipop
}
Edit: This SDK...
Which is better option to use for dividing an integer number by 2?
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Use the operation that best describes what you are trying to do.
If you are treating the number as a sequence of bits, use bitshift.
If you are treating it as a numerical value, use division.
Note that they are not exactly equivalent. They can give different results for negative integers...
How can I get the external SD card path for Android 4.0+?
...al String[] lines = s.split("\n");
for (String line : lines) {
if (!line.toLowerCase(Locale.US).contains("asec")) {
if (line.matches(reg)) {
String[] parts = line.split(" ");
for (String part : parts) {
if (part.startsWith("...
Python multiprocessing pool.map for multiple arguments
...ort product
def merge_names(a, b):
return '{} & {}'.format(a, b)
if __name__ == '__main__':
names = ['Brown', 'Wilson', 'Bartlett', 'Rivera', 'Molloy', 'Opie']
with multiprocessing.Pool(processes=3) as pool:
results = pool.starmap(merge_names, product(names, repeat=2))
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How to check if anonymous object has a method?
How can I check if an anonymous object that was created as such:
6 Answers
6
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Is there any performance gain in indexing a boolean field?
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Not really. You should think about it like a book. If there were only 3 kinds of words in a book and you index all of them, you would have the same number of index pages as normal pages.
There would be a performance gain if there are relatively few records of one value. For...
Finding the index of elements based on a condition using python list comprehension
...xes for this at all, but just deal with the values—[value for value in a if value > 2]. Usually dealing with indexes means you're not doing something the best way.
If you do need an API similar to Matlab's, you would use numpy, a package for multidimensional arrays and numerical math in Python ...