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How do you convert a byte array to a hexadecimal string, and vice versa?
How can you convert a byte array to a hexadecimal string, and vice versa?
45 Answers
4...
MySQL Conditional Insert
... WHERE user = 123
AND item = 456)
In this, dual is a table with one row only (found originally in Oracle, now in mysql too). The logic is that the SELECT statement generates a single row of data with the required values, but only when the v...
Get the first element of each tuple in a list in Python [duplicate]
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@Creak - x,_ is just using tuple unpacking. And you are right, the documentation on this is hard to come by. I found this link and this one which should explain how it works. Also, the _ is just a normal variable. I could have done x,y and got the same results. How...
Which is more preferable to use: lambda functions or nested functions ('def')?
...efs are just syntactic sugar for an assignment, so the result is the same, and they are a lot more flexible and readable.
lambdas can be used for use once, throw away functions which won't have a name.
However, this use case is very rare. You rarely need to pass around unnamed function objects.
T...
What's the difference between nohup and ampersand
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nohup catches the hangup signal (see man 7 signal) while the ampersand doesn't (except the shell is confgured that way or doesn't send SIGHUP at all).
Normally, when running a command using & and exiting the shell afterwards, the shell will terminate the sub-command with the hangup sign...
The new syntax “= default” in C++11
I don't understand why would I ever do this:
5 Answers
5
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GCC compile error with >2 GB of code
...+
1/10.*s.x14*s.x15*csc[49302] - 3/5.*s.x14*s.x15*csc[49303] -...
and
double csc19295 = + s.ds0*s.ds1*s.ds2 * ( -
32*s.x12pow2*s.x15*s.x34*s.mbpow2*s.mWpowinv2 -
32*s.x12pow2*s.x15*s.x35*s.mbpow2*s.mWpowinv2 -
32*s.x12pow2*s.x15*s.x35*s.x45*s.mWpowinv2 -...
rig...
Qt: can't find -lGL error
... edited Jul 30 '18 at 14:05
Rando Hinn
1,1151717 silver badges3232 bronze badges
answered Aug 29 '13 at 6:15
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Linq code to select one item
...ion methods directly like:
var item = Items.First(i => i.Id == 123);
And if you don't want to throw an error if the list is empty, use FirstOrDefault which returns the default value for the element type (null for reference types):
var item = Items.FirstOrDefault(i => i.Id == 123);
if (ite...
how to remove X-Powered-By in ExpressJS [duplicate]
I want to remove X-Powered-By for Security,Save Bandwidth in ExpressJS(node.js). how to do it?
it could be filter(app.use) ?
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