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What's the difference between lapply and do.call?
...he above means something like below.
list( sum( L[[1]]) , sum( L[[2]]))
Now let us do the same thing for do.call
do.call(sum, L)
It means
sum( L[[1]], L[[2]])
In our example, it returns 21. In short, lapply always returns a list while the return type of do.call really depends on the funct...
Configure Flask dev server to be visible across the network
...
I don't know if anyone else has experienced it, but I tried this method first as per the QuickStart docs, but for some odd reason the IP kept running at 127.0.0.1 (I setup my Flask executable properly, or so it seemed, wasn't sure wha...
What does {0} mean when initializing an object?
...cted non-static data members, no base classes, and no virtual functions.
Now, using {0} to initialize an aggregate like this is basically a trick to 0 the entire thing. This is because when using aggregate initialization you don't have to specify all the members and the spec requires that all uns...
How do I use Maven through a proxy?
...iting the settings.xml file in my .m2 folder.
My settings.xml is like this now:
<settings>
<proxies>
<proxy>
<id>genproxy</id>
<active>true</active>
<protocol>http</protocol>
<host>proxyHost</host>
...
How to detect if a property exists on an ExpandoObject?
...ewBag.EnableThinger)
{
// Do some stuff when EnableThinger is true
}
Now get rid of the declaration of EnableThinger. Same code compiles and runs properly. No need for reflection.
Unlike ViewBag, ExpandoObject will throw if you check for null on a property that doesn't exist. In order to get ...
Why is it Valid to Concatenate Null Strings but not to Call “null.ToString()”?
...
@Svish yes, now I think of it again, it is a null object, so you're right, it won't work. It wouldn't in Java neither: null pointer exception. Never mind. Tnx for your reply! [edit: tested it in Java: NullPointerException. With the diffe...
Why does volatile exist?
... in straight C. We used a hardware managed 16 bit value as a semaphore to know when the other guy was done. Essentially we did this:
void waitForSemaphore()
{
volatile uint16_t* semPtr = WELL_KNOWN_SEM_ADDR;/*well known address to my semaphore*/
while ((*semPtr) != IS_OK_FOR_ME_TO_PROCEED);
}...
What is the most efficient way to store a list in the Django models?
...izing and deserializing values from the database to Python and vice versa. Now you can easily import and use our custom field in the model class:
from django.db import models
from custom.fields import SeparatedValuesField
class Person(models.Model):
name = models.CharField(max_length=64)
...
How to replace multiple substrings of a string?
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nice! if you use python3 use items instead of iteritems (now removed in dicts stuff).
– e.arbitrio
Oct 24 '16 at 12:09
2
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How do I find the stack trace in Visual Studio?
...shortcut (while debugging and stopped at a breakpoint) is:
Ctrl+Alt+C and now you can also use Ctrl+L
The screenshot is pretty old.
Here is one for Visual Studio 2019 (under the debug menu):
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