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How can I implode an array while skipping empty array items?
...
You can use array_filter():
If no callback is supplied, all entries of input equal to FALSE (see converting to boolean) will be removed.
implode('-', array_filter($array));
Obviously this will not work if you have 0 (or any other value that evaluat...
cv2.imshow command doesn't work properly in opencv-python
...://txt.arboreus.com/2012/07/11/highgui-opencv-window-from-ipython.html
If you run an interactive ipython session, and want to use highgui
windows, do cv2.startWindowThread() first.
In detail: HighGUI is a simplified interface to display images and
video from OpenCV code. It should be as...
micro:bit 实验03 - 做一块实时温度看板 · App Inventor 2 中文网
...示()
}
procedure 刷新显示() {
标签_温度.Text = 当前温度
if 当前温度 >= 30 {
标签_温度.TextColor = "&HFFE53935"
} else if 当前温度 最高 {
global 最高 = 当前温度
}
if 当前温度 < 最低 {
global 最低 = 当前温度
}
标签_状态.Text ...
How do I test a file upload in rails?
...ls 3, Rails 5), which will search your fixtures directory for the file specified and will make it available as a test file for the controller in functional testing. To use it:
1) Put your file to be uploaded in the test in your fixtures/files subdirectory for testing.
2) In your unit test you can ...
Extracting specific columns in numpy array
...asy question but say I have an MxN matrix. All I want to do is extract specific columns and store them in another numpy array but I get invalid syntax errors.
Here is the code:
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What is the maximum recursion depth in Python, and how to increase it?
...t a particularly efficient technique. Rewriting the algorithm iteratively, if possible, is generally a better idea.
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How to increment a NSNumber
... you think, and may be slower at times (it could default to "valueForKey:" if no synthesised accessor exists for the "property" (in your case intValue) exists. intValue was never defined as as @property of NSNumber.
– Motti Shneor
Jul 21 at 9:19
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Converting integer to binary in python
...ro-padded on the left
b converts the number to its binary representation
If you're using a version of Python 3.6 or above, you can also use f-strings:
>>> f'{6:08b}'
'00000110'
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Slide right to left?
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The only trouble is that if there is content inside, it "squashes" it horizontally, causing controls to move about/resize/wrap etc. Is there a good solution for that?
– Neil Barnwell
May 15 '17 at 22:51
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Rails: select unique values from a column
...ts. Not plain ratings. And from uniq's point of view, they are completely different. You can use this:
Model.select(:rating).map(&:rating).uniq
or this (most efficient)
Model.uniq.pluck(:rating)
# rails 5+
Model.distinct.pluck(:rating)
Update
Apparently, as of rails 5.0.0.1, it works onl...