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Is there a way to pass optional parameters to a function?
Is there a way in Python to pass optional parameters to a function while calling it and in the function definition have some code based on "only if the optional parameter is passed"
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Python matplotlib multiple bars
How to plot multiple bars in matplotlib, when I tried to call the bar function multiple times, they overlap and as seen the below figure the highest value red can be seen only.
How can I plot the multiple bars with dates on the x-axes?
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MongoDB Many-to-Many Association
... user document:
{name:"Joe"
,roles:["Admin","User","Engineer"]
}
To get all the Engineers, use:
db.things.find( { roles : "Engineer" } );
If you want to maintain the roles in separate documents then you can include the document's _id in the roles array instead of the name:
{name:"Joe"
,roles:...
Queries vs. Filters
...erefore faster than queries. Have a look here too. Let's say a query is usually something that the users type and pretty much unpredictable, while filters help users narrowing down the search results , for example using facets.
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How to concatenate two MP4 files using FFmpeg?
...pe f is for only listing files. I added | sort to sort the files alphabetically; because find reads them in order as saved on filesystem. Works also for files with whitespaces.
– erik
Dec 2 '16 at 14:15
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Split a string by a delimiter in python
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@EndenDragon The for loop will automatically apply x.strip() and return a list of matches without whitespace on either side. The devil is in the details.
– Sébastien Vercammen
Jun 29 '16 at 13:59
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Python None comparison: should I use “is” or ==?
...ject None, so when you do my_var is None, you're checking whether they actually are the same object (not just equivalent objects)
In other words, == is a check for equivalence (which is defined from object to object) whereas is checks for object identity:
lst = [1,2,3]
lst == lst[:] # This is Tr...
Find the files existing in one directory but not in the other [closed]
...rison is to use find with md5sum, then a diff.
Example:
Use find to list all the files in the directory then calculate the md5 hash for each file and pipe it to a file:
find /dir1/ -type f -exec md5sum {} \; > dir1.txt
Do the same procedure to the another directory:
find /dir2/ -type f -exe...
Efficient way to apply multiple filters to pandas DataFrame or Series
...s to apply several filters to a Pandas DataFrame or Series object. Essentially, I want to efficiently chain a bunch of filtering (comparison operations) together that are specified at run-time by the user.
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Avoid browser popup blockers
...m javascript that is not invoked by direct user action. That is, you can call window.open in response to a button click without getting hit by the popup blocker, but if you put the same code in a timer event it will be blocked. Depth of call chain is also a factor - some older browsers only look a...