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What are the rules for evaluation order in Java?
...that is assigned in the indexing operation. Precedence and associativity alone say nothing about whether the a[b] is evaluated before or after the b=0.
Again, this is just the same as: A()[B()] = C() -- All we know is that the indexing has to happen before the assignment. We don't know whether A()...
Painless way to install a new version of R?
...de process for R (probably more relevant on Windows than Linux). Does anyone have a good trick for doing the upgrade, from installing the software to copying all the settings/packages over?
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Why are variables “i” and “j” used for counters?
...s, like if you have a bunch of variables x1, x2, ... xn, then an arbitrary one will be known as xi.
As for why it's that way, I imagine SLaks is correct and it's because I is the first letter in Index.
share
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Getting the first character of a string with $str[0]
...d I'm pretty sure is much faster than the substr() method).
There is only one caveat with both methods: they will get the first byte, rather than the first character. This is important if you're using multibyte encodings (such as UTF-8). If you want to support that, use mb_substr(). Arguably, you s...
mysqli or PDO - what are the pros and cons? [closed]
... stuff like prepared statements and transaction support. Some projects use one, some the other. There is little realistic likelihood of us ever moving to another RDBMS.
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Invert “if” statement to reduce nesting
...ng the 2nd and 3rd "if" to "else if" to increase readability even more. If one overlooks the "return" statement it would still be clear that the following case is only checked if the previous one failed, i.e. that the order of the checks is important.
– foraidt
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In which case do you use the JPA @JoinTable annotation?
...refuse to start up by printing the following error:
org.hibernate.AnnotationException:
Associations marked as mappedBy must not define database mappings
like @JoinTable or @JoinColumn
Let's pretend that you have an entity named Project and another entity named Task and each project can ...
How to limit the amount of concurrent async I/O operations?
...to control max concurrent I/O requests similar to a sliding window pattern one request completes, leaves the semaphore and the next one gets in.
usage:
await ForEachAsync(urlStrings, YourAsyncFunc, optionalMaxDegreeOfConcurrency);
public static Task ForEachAsync<TIn>(
IEnumerable&l...
Matplotlib 2 Subplots, 1 Colorbar
...olorbar() with a list of axes.
From the documentation:
ax
None | parent axes object(s) from which space for a new colorbar axes will be stolen. If a list of axes is given they will all be resized to make room for the colorbar axes.
import numpy as np
import matplotlib.pyplot as ...
What is the bower (and npm) version syntax?
...ticking to ~, the syntax is consistent all the way down a list of 70+ versioned dependencies, regardless of which beginning patch number is acceptable.
Anyway, there's still more to SemVer, but I won't try to detail it all here. Check it out on the node semver package's readme. And be sure to use ...