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Why does the indexing start with zero in 'C'?
...e of an array is essentially a pointer [but see the comments], a reference to a memory location, and so the expression array[n] refers to a memory location n elements away from the starting element. This means that the index is used as an offset. The first element of the array is exactly contained i...
How to easily resize/optimize an image size with iOS?
...tion is downloading a set of image files from the network, and saving them to the local iPhone disk. Some of those images are pretty big in size (widths larger than 500 pixels, for instance). Since the iPhone doesn't even have a big enough display to show the image in its original size, I'm planning...
How do I modify fields inside the new PostgreSQL JSON datatype?
...ctionality within PostgreSQL itself (but none for json; casts are required to manipulate json values).
Merging 2 (or more) JSON objects (or concatenating arrays):
SELECT jsonb '{"a":1}' || jsonb '{"b":2}', -- will yield jsonb '{"a":1,"b":2}'
jsonb '["a",1]' || jsonb '["b",2]' -- will yield j...
Delete column from pandas DataFrame
...u've guessed, the right syntax is
del df['column_name']
It's difficult to make del df.column_name work simply as the result of syntactic limitations in Python. del df[name] gets translated to df.__delitem__(name) under the covers by Python.
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Numpy - add row to array
How does one add rows to a numpy array?
9 Answers
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Can I delete a git commit but keep the changes?
In one of my development branches, I made some changes to my codebase. Before I was able to complete the features I was working on, I had to switch my current branch to master to demo some features. But just using a "git checkout master" preserved the changes I also made in my development branch, th...
Is it possible to install APK file if more than one emulators/devices are connected [duplicate]
I know how to install the apk file in to the emulator by command prompt and all that.
But i want to know is it possible to install same apk file in to multiple emulator by giving any specific name ?
Actually i have to test one apk file in to many device. and for that i have started many device. I kn...
Better explanation of when to use Imports/Depends
...he " Writing R Extensions " manual provides the following guidance on when to use Imports or Depends:
4 Answers
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Getting a map() to return a list in Python 3.x
I'm trying to map a list into hex, and then use the list elsewhere. In python 2.6, this was easy:
9 Answers
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How to create an HTML button that acts like a link?
I would like to create an HTML button that acts like a link. So, when you click the button, it redirects to a page. I would like it to be as accessible as possible.
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