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JavaScript checking for null vs. undefined and difference between == and ===
...is the difference between the null and undefined?
They're both values usually used to indicate the absence of something. undefined is the more generic one, used as the default value of variables until they're assigned some other value, as the value of function arguments that weren't provided when ...
Linear Regression and group by in R
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fits <- lmList(response ~ year | state, data=d)
fits
#------------
Call: lmList(formula = response ~ year | state, data = d)
Coefficients:
(Intercept) year
CA -1.34420990 0.17139963
NY 0.00196176 -0.01852429
Degrees of freedom: 20 total; 16 residual
Residual standard error: 0.820...
Print PHP Call Stack
I'm looking for a way to print the call stack in PHP.
15 Answers
15
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Zero-based month numbering [closed]
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The use of zero to start counting is actually an optimization trick from Assembly programmers. Instead of assigning 1 to the count register, they XOR'ed the register with itself, which was slightly faster in CPU cycles. This meant that counting would start with 0 an...
Why do we use volatile keyword? [duplicate]
...imizing the while loop. That is where the volatile keyword plays its role. All you need to do is this,
volatile int some_int = 100; //note the 'volatile' qualifier now!
In other words, I would explain this as follows:
volatile tells the compiler that,
"Hey compiler, I'm volatile and, you
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IntelliJ does not show project folders
...for me. I had to "Add Content Root" on that screen. Then for some reason all the folders magically appeared.
– Lavamantis
Jun 25 '15 at 20:39
2
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Manually adding a Userscript to Google Chrome
Instead of "installing" User-Scripts I found many tutorials on the web to add it manually. All of them told me to do the same steps:
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How to change navbar collapse threshold using Twitter bootstrap-responsive?
... I can't think of any way to achieve the overriding without restating all the CSS declarations.
– methodofaction
Feb 23 '12 at 5:15
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PHP server on local machine?
...d I'm wanting to test my PHP files without uploading them to my host. Basically testing them on my own machine before I upload them. How do I do that?
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What is the difference between Spring, Struts, Hibernate, JavaServer Faces, Tapestry?
...ased presentation framework.
JavaServer Pages is a view technology used by all mentioned presentation framework for the view.
Tapestry is another component-based presentation framework.
So, to summarize:
Struts 2, JSF, Tapestry (and Wicket, Spring MVC, Stripes) are presentation frameworks. If yo...