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Select first 4 rows of a data.frame in R
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Use head:
dnow <- data.frame(x=rnorm(100), y=runif(100))
head(dnow,4) ## default is 6
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How to access object attribute given string corresponding to name of that attribute
... and hasattr for testing whether or not an object has a specific attr though in that case using the three argument form getattr(object, attrname, default) is often better.
– Duncan
Apr 10 '10 at 11:20
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How to hide Bootstrap modal with javascript?
... window, use the browser's console to try
$('#myModal').modal('hide');
If it works (and the modal closes) then you know that your close Javascript is not being sent from the server to the browser correctly.
If it doesn't work then you need to investigate further on the client what is happening....
How to subtract 2 hours from user's local time?
...ursBefore.setHours(twoHoursBefore.getHours() - 2);
And don't worry about if hours you set will be out of 0..23 range.
Date() object will update the date accordingly.
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Removing non-repository files with git?
...pt when the Git configuration variable clean.requireForce is set to true. If its set to false, then -ff is needed for cleaning diretories
– Adam
Dec 24 '16 at 8:47
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matplotlib.pyplot will not forget previous plots - how can I flush/refresh?
...ly, you could do plt.cla() to just clear the current axes.
To clear a specific axes, useful when you have multiple axes within one figure, you could do for example:
fig, axes = plt.subplots(nrows=2, ncols=2)
axes[0, 1].clear()
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Deny all, allow only one IP through htaccess
...ost shows how to do in newer versions. And one should also be considering, if the server is using a proxy, since that would then display the proxy-IP for the visitor. This post suggests a solution to that.
– Zeth
Oct 24 '18 at 3:13
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Naming convention for unique constraint
...it's a constraint.
It could be used as a key of course, and uniquely identifies a row, but it isn't the key.
An example would be that the key is "ThingID", a surrogate key used in place of ThingName the natural key. You still need to constrain ThingName: it won't be used as a key though.
I'd als...
Convert list to dictionary using linq and not worrying about duplicates
...e's the obvious, non linq solution:
foreach(var person in personList)
{
if(!myDictionary.Keys.Contains(person.FirstAndLastName))
myDictionary.Add(person.FirstAndLastName, person);
}
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How do you log content of a JSON object in Node.js?
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Try this one:
console.log("Session: %j", session);
If the object could be converted into JSON, that will work.
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