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Overriding the java equals() method - not working?
I ran into an interesting (and very frustrating) issue with the equals() method today which caused what I thought to be a well tested class to crash and cause a bug that took me a very long time to track down.
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Get records with max value for each group of grouped SQL results
...alue for.
You avoid complicated subqueries that try to find the max() etc, and also the problems of returning multiple rows when there are more than one with the same maximum value (as the other answers would do)
Note: This is a mysql-only solution. All other databases I know will throw an SQL synta...
Value cannot be null. Parameter name: source
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I had this one a while back, and the answer isn't necessarily what you'd expect. This error message often crops up when your connection string is wrong.
At a guess, you'll need something like this:
<connectionStrings>
<add name="hublisherE...
Plot a legend outside of the plotting area in base graphics?
.... Normally this would get clipped to the plot region, but do par(xpd=TRUE) and with a bit of adjustment you can get a legend as far right as it can go:
set.seed(1) # just to get the same random numbers
par(xpd=FALSE) # this is usually the default
plot(1:3, rnorm(3), pch = 1, lty = 1, type = "o"...
JavaScript string encryption and decryption?
I'm interested in building a small app for personal use that will encrypt and decrypt information on the client side using JavaScript. The encrypted information will be stored in a database on a server, but never the decrypted version.
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How to prevent the activity from loading twice on pressing the button
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In the button's event listener, disable the button and show another activity.
Button b = (Button) view;
b.setEnabled(false);
Intent i = new Intent(this, AnotherActitivty.class);
startActivity(i);
Override onResume() to re-enable the button.
@Override
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How to convert a factor to integer\numeric without loss of information?
...actor:
In particular, as.numeric applied to
a factor is meaningless, and may
happen by implicit coercion. To
transform a factor f to
approximately its original numeric
values, as.numeric(levels(f))[f] is
recommended and slightly more
efficient than
as.numeric(as.character(f)).
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Looping through array and removing items, without breaking for loop
I have the following for loop, and when I use splice() to remove an item, I then get that 'seconds' is undefined. I could check if it's undefined, but I feel there's probably a more elegant way to do this. The desire is to simply delete an item and keep on going.
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Difference between CSS3 transitions' ease-in and ease-out
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CSS3's transitions and animations support easing, formally called a "timing function". The common ones are ease-in, ease-out, ease-in-out, ease, and linear, or you can specify your own using cubic-bezier().
ease-in will start the animation sl...
Pass arguments to Constructor in VBA
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Here's a little trick I'm using lately and brings good results. I would like to share with those who have to fight often with VBA.
1.- Implement a public initiation subroutine in each of your custom classes. I call it InitiateProperties throughout all my classes....