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How to count the number of true elements in a NumPy bool array
...type=bool)
>>> np.sum(boolarr)
5
Of course, that is a bool-specific answer. More generally, you can use numpy.count_nonzero.
>>> np.count_nonzero(boolarr)
5
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WebSockets vs. Server-Sent events/EventSource
...ta to browsers. To me they seem to be competing technologies. What is the difference between them? When would you choose one over the other?
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Checking for an empty field with MySQL
...handle both, use:
email > ''
which can benefit from the range access if you have lots of empty email record (both types) in your table.
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How to put comments in Django templates
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True, but if you have an {% extends "file.html" %} tag you should put that on the very top of the template file even before the {% comment %}...{% endcomment %}, otherwise you'll get an <ExtendsNode: extends "file.html"> must be ...
requestFeature() must be called before adding content
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What if you need to show one layout without a title bar and then show one with a title bar? You will have to use requestWindowFeature(Window.FEATURE_NO_TITLE) to hide it, then setContentView() for your first layout, then requestWi...
REST API Best practices: args in query string vs in request body
...ded/downloaded to/from the server and the query parameters are used to specify the exact data requested. For example when you upload a file you specify the name, mime type, etc. in the body but when you fetch list of files you can use the query parameters to filter the list by some property of the f...
How to find the last field using 'cut'
...bash to run pipelines, not to process data in bulk. I mean, this is great if you have one line of text already in a shell variable, or if you want to do while IFS= read -ra array_var; do :;done <(cmd) to process a few lines. But for a big file, rev|cut|rev is probably faster! (And of course aw...
Create a table without a header in Markdown
...d multiline_tables extensions)
Flexmark: A parser in Java.
CSS solution
If you're able to change the CSS of the HTML output you can however leverage the :empty pseudo class to hide an empty header and make it look like there is no header at all.
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Creating an instance of class
What's the difference between lines 1 , 2 , 3 , 4?
3 Answers
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Using Core Data, iCloud and CloudKit for syncing and backup and how it works together
...ble even when the device is offline. You don't have to write any cloud-specific code, you just need to add listening for incoming changes (which is a lot like changes made on a different managed object context).
CloudKit is not related to Core Data. It's not a sync system, it's a transfer system. Me...