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Getting the count of unique values in a column in bash
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To see a frequency count for column two (for example):
awk -F '\t' '{print $2}' * | sort | un...
How can I log the stdout of a process started by start-stop-daemon?
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11 Answers
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Is it possible to modify variable in python that is in outer, but not global, scope?
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Python 3.x has the nonlocal keyword. I think this does what you want, but I'm not sure if you...
How to add a new row to an empty numpy array
...4)
Then be sure to append along axis 0:
arr = np.append(arr, np.array([[1,2,3]]), axis=0)
arr = np.append(arr, np.array([[4,5,6]]), axis=0)
But, @jonrsharpe is right. In fact, if you're going to be appending in a loop, it would be much faster to append to a list as in your first example, then ...
How to express infinity in Ruby?
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If you use ruby 1.9.2, you can use:
>> Float::INFINITY #=> Infinity
>> 3 < ...
Why does installing Nokogiri on Mac OS fail with libiconv is missing?
I've been trying to install Nokogiri on Mac OS 10.9.3 and whatever I try, the install fails in the end with the following error message:
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Drop all duplicate rows across multiple columns in Python Pandas
...t pandas as pd
df = pd.DataFrame({"A":["foo", "foo", "foo", "bar"], "B":[0,1,1,1], "C":["A","A","B","A"]})
df.drop_duplicates(subset=['A', 'C'], keep=False)
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Analyze audio using Fast Fourier Transform
...ly spaced frequencies, starting at 0. Because your sampling frequency is 44100 samples / sec. and the number of points in your FFT is 256, your frequency spacing is 44100 / 256 = 172 Hz (approximately)
The first coefficient in your array will be the 0 frequency coefficient. That is basically the av...
Delete rows from a pandas DataFrame based on a conditional expression involving len(string) giving K
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When you do len(df['column name']) you are just getting one number, namely the number of rows ...
What’s the difference between “Array()” and “[]” while declaring a JavaScript array?
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18 Answers
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