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Questions - numpy

Lost on how to append numpy vectors/matrices/arrays

I'm currently trying to build a practice linear parameter estimation python program using numpy but I've never written in python before and I'm very loose with numpy. I have a series of x,y data point...
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Eliot Shedlock

python

numpy

linear-programming

Votes: 0

Answers: 1

Latest Answer

To fetch just the Y values, use data_points[:,1]. That says "use all rows, but only element 1 (counting from 0) of the rows". That's a 5-element vector. Not sure why you're expecting (3,1)...
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Tim Roberts

Changing values in a dataframe based on multiple conditions, using np.select

I would like to change values in a dataframe using np.select However, I'm getting an error and google didn't find any solution for similar issues. Could somebody help me out? Thank you in advance for ...
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Amilovsky

python

pandas

numpy

select

Votes: 0

Answers: 1

Latest Answer

You could try this instead - I believe rounding the decimals to zero digits obeys all your conditions as well : # default decimals is 0 df_new = df.round() # or this if you need more control on each...
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skimmed_code1

Expand 2-D Numpy integer Array as binary but in parallel

I want to convert arrays of integers to 0 or 1s, padding with 0s if the other array possesses the larger value. Examples: ex1 = np.array([[0],[3]]) => array([[0,0,0],[1,1,1]]) ex2 = np.array([[2,...
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Shun

python

numpy

numpy-ndarray

confusion-matrix

Votes: 0

Answers: 1

Latest Answer

Came up with this approach: def expand_multi_bin(a): # Create result array n = np.max(a, axis=0).sum() d = a.shape[0] newa = np.zeros(d*n).reshape(d,n) row=0 for x in np.ndite...
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Shun

Why does numpy change the order of columns in pandas dataframe?

I am reading data from EXCEL to a pandas DataFrame: df = pd.read_excel(file, sheet_name='FactoidList', ignore_index=False, sort=False) Applying sort=False preserves the original order of my columns. B...
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OnceUponATime

python

pandas

numpy

Votes: 0

Answers: 1

Latest Answer

Reviewing my script, I figured out that the problem isn't numpy but pandas. Before applying my condition list, I am adding the dataframe df with the explicit sort=False statement to another dataframe ...
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OnceUponATime

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