53
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5
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2.6K
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What is the difference between ndarray and array in numpy?
What is the difference between ndarray and array in Numpy? And where can I find the implementations in the num
57
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8
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380
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Most efficient way to reverse a numpy array
Believe it or not, after profiling my current code, the repetitive operation of numpy array reversion ate a gi
61
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20
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2.9K
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Saving a Numpy array as an image
I have a matrix in the type of a Numpy array. How would I write it to disk it as an image? Any format works
58
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6
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I have two simple one-dimensional arrays in NumPy. I should be able to concatenate them using numpy.concatenat
47
votes
17
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2.5K
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How do I check which version of NumPy I'm using?
How can I check which version of NumPy I'm using? (FYI this question has been edited because both the qu
50
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7
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1.3K
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Comparing two NumPy arrays for equality, element-wise
What is the simplest way to compare two NumPy arrays for equality (where equality is defined as: A = B iff for
62
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23
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2.8K
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What does axis in pandas mean?
Here is my code to generate a dataframe: import pandas as pd import numpy as np dff = pd.DataFrame(np.random
64
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14
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1.7K
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NumPy array is not JSON serializable
After creating a NumPy array, and saving it as a Django context variable, I receive the following error when l
62
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8
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1.2K
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How to convert a PIL Image into a numpy array?
Alright, I'm toying around with converting a PIL image object back and forth to a numpy array so I can do
51
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4
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1.3K
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How to convert 2D float numpy array to 2D int numpy array?
How to convert real numpy array to int numpy array? Tried using map directly to array but it did not work.
54
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3
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2.6K
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What is the difference between flatten and ravel functions in numpy?
import numpy as np y = np.array(((1,2,3),(4,5,6),(7,8,9))) OUTPUT: print(y.flatten()) [1 2 3 4 5 6
60
votes
9
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1.3K
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Creating a Pandas DataFrame from a Numpy array: How do I specify the index column and column headers?
I have a Numpy array consisting of a list of lists, representing a two-dimensional array with row labels and c
53
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13
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2.3K
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Converting between datetime, Timestamp and datetime64
How do I convert a numpy.datetime64 object to a datetime.datetime (or Timestamp)? In the following code, I cr
65
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6
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1.5K
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What is the difference between Numpy's array() and asarray() functions?
What is the difference between Numpy's array() and asarray() functions? When should you use one rather th
52
votes
5
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612
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Converting NumPy array into Python List structure?
How do I convert a NumPy array to a Python List (for example [[1,2,3],[4,5,6]] ), and do it reasonably fast?
55
votes
17
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3.1K
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How to add an extra column to a NumPy array
Let’s say I have a NumPy array, a: a = np.array([ [1, 2, 3], [2, 3, 4] ]) And I would like
55
votes
15
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786
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How do I create an empty array/matrix in NumPy?
I can't figure out how to use an array or matrix in the way that I would normally use a list. I want to c
54
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7
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1.3K
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Difference between numpy.array shape (R, 1) and (R,)
In numpy, some of the operations return in shape (R, 1) but some return (R,). This will make matrix multiplica
53
votes
14
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1.8K
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How to pretty-print a numpy.array without scientific notation and with given precision?
I'm curious, whether there is any way to print formatted numpy.arrays, e.g., in a way similar to this: x
61
votes
11
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1.4K
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What does numpy.random.seed(0) do?
What does np.random.seed do in the below code from a Scikit-Learn tutorial? I'm not very familiar with Nu
