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Assigning a variable NaN in python without numpy
...t;>> import math
>>> math.isnan(nan)
True
Before Python 3.5, one could use float("nan") (case insensitive).
Note that checking to see if two things that are NaN are equal to one another will always return false. This is in part because two things that are "not a number" cannot (str...
“Width equals height” constraint in Interface Builder
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Update Xcode 5.1b5
Ctrl+click and drag from a view and release while the pointer is over the view. Select "Aspect Ratio". It will create a constraint where the first and second item is the view.
Before Xcode 5.1
You can't because t...
Can a for loop increment/decrement by more than one?
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265
Use the += assignment operator:
for (var i = 0; i < myVar.length; i += 3) {
Technically, y...
Way to read first few lines for pandas dataframe
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185
I think you can use the nrows parameter. From the docs:
nrows : int, default None
Number ...
How to declare a friend assembly?
...ProtocolBuffers.Test,PublicKey="+
"00240000048000009400000006020000002400005253413100040000010001008179f2dd31a648"+
"2a2359dbe33e53701167a888e7c369a9ae3210b64f93861d8a7d286447e58bc167e3d99483beda"+
"72f738140072bb69990bc4f98a21365de2c105e848974a3d210e938b0a56103c0662901efd6b78"+
"0ee6dbe977923d46a8f...
Pull to refresh UITableView without UITableViewController
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465
Add a refresh control directly to a UITableView without using a UITableViewController:
override...
Insert a row to pandas dataframe
... # sorting by index
And you get, as desired:
A B C
0 2 3 4
1 5 6 7
2 7 8 9
See in Pandas documentation Indexing: Setting with enlargement.
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Get value of dynamically chosen class constant in PHP
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185
$id = constant("ThingIDs::$thing");
http://php.net/manual/en/function.constant.php
...
How to use a custom comparison function in Python 3?
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53
Use the key argument (and follow the recipe on how to convert your old cmp function to a key fu...