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typeof !== “undefined” vs. != null
...n the two. In many cases, == can be better, because it tests for both null and undefined.
– seanmonstar
Jun 19 '12 at 16:58
10
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Scatterplot with too many points
...+ geom_point(alpha = 0.3)
Another convenient way to deal with this is (and probably more appropriate for the number of points you have) is hexagonal binning:
ggplot(df,aes(x=x,y=y)) + stat_binhex()
And there is also regular old rectangular binning (image omitted), which is more like your tr...
Laravel migration: unique key is too long, even if specified
...l', 250);
Which is the default, actually:
$table->string('email');
And you should be good.
For Laravel 5.4 you can find a solution in this Laravel 5.4: Specified key was too long error, Laravel News post:
As outlined in the Migrations guide to fix this all you have to do is edit your AppSe...
How do I detect if software keyboard is visible on Android Device or not?
Is there a way in Android to detect if the software (a.k.a. "soft") keyboard is visible on screen?
30 Answers
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How do I get the path of the current executed file in Python?
...always loaded from a file. If you create a module with the following code and put it in the same directory as your main script, then the main script can import the module and use that to locate itself.
some_path/module_locator.py:
def we_are_frozen():
# All of the modules are built-in to the ...
How do I retrieve the number of columns in a Pandas data frame?
How do you programmatically retrieve the number of columns in a pandas dataframe? I was hoping for something like:
6 Answer...
What exactly is Heroku?
I just started learning Ruby on rails and I was wondering what Heroku really is? I know that its a cloud that helps us to avoid using servers? When do we actually use it?
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Disable JavaScript error in WebBrowser control
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This disables the script errors and also disables other windows.. such as the NTLM login window or the client certificate accept window. The below will suppress only javascript errors.
// Hides script errors without hiding other dialog boxes.
private voi...
Removing duplicate rows from table in Oracle
I'm testing something in Oracle and populated a table with some sample data, but in the process I accidentally loaded duplicate records, so now I can't create a primary key using some of the columns.
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Disable Rails SQL logging in console
Is there a way to disable SQL query logging when I'm executing commands in the console? Ideally, it would be great if I can just disable it and re-enable it with a command in the console.
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