What does [:, :] mean on NumPy arrays - Stack Overflow
numpy uses tuples as indexes. In this case, this is a detailed slice assignment. [0] #means line 0 of your matrix [(0,0)] #means cell at 0,0 of your matrix [0:1] #means lines 0 to 1 excluded of your matrix [:1] #excluding the first value means all lines until line 1 excluded [1:] #excluding the last param mean all lines starting form line 1 included [:] #excluding both means all lines [::2] # ...
How do I check which version of NumPy I'm using?
Oct 5, 2009 · 1. Just a slight caution that it's possible that you may have python and python 3 both installed with numpy. Then when doing the pip list | grep numpymethod it will show one of the two (typically the python 3's numpy version). When you run the shownumpy.pyprogram on both python and python 3, they will show you exactly what version is on each ...
Error "Import Error: No module named numpy" on Windows
Mar 19, 2019 · pip3 install numpy" results in "Requirement already satisfied: numpy in c:\users\peter\appdata\local\programs\python\python36-32\lib\site-packages". You'd expect python's "import numpy" would be able to find it, but no. ModuleNotFoundError: No module named 'numpy' So this answer may work in some narrow context, but not in general.
Multiple conditions using 'or' in numpy array - Stack Overflow
numpy logical_and and logical_or are the ufuncs that you want (I think) Note that & is not logical and, it is bitwise and. This still works for you because (a>10) returns a logical array (e.g. 1's and 0's) as does your second condition. So, in this case, "logical and" and "bitwise and" are equivalent (same with logical and bitwise or).
How do I read CSV data into a record array in NumPy?
Aug 19, 2010 · You can then easily, and with less time even for huge amount of data, load your data in a NumPy array. import pandas as pd store = pd.HDFStore('dataset.h5') data = store['mydata'] store.close() # Data in NumPy format data = data.values
python - Factorial in numpy and scipy - Stack Overflow
Feb 13, 2014 · 104. You can import them like this: <function math.factorial>, <function math.factorial>) scipy.math.factorial and numpy.math.factorial seem to simply be aliases/references for/to math.factorial, that is scipy.math.factorial is math.factorial and numpy.math.factorial is math.factorial should both give True.
How do I compute derivative using Numpy? - Stack Overflow
Mar 26, 2012 · 23. Assuming you want to use numpy, you can numerically compute the derivative of a function at any point using the Rigorous definition: def d_fun (x): h = 1e-5 #in theory h is an infinitesimal return (fun (x+h)-fun (x))/h. You can also use …
How to remove specific elements in a numpy array
Jun 12, 2012 · python -m timeit -s "import numpy as np" -s "import itertools" -s "a = np.array(list(range(10000)))" -s "index=[i for i in range(10000) if i % 2 == 0]" "a = np.array(list(itertools.compress(a, [i not in index for i in range(len(a))])))" 10 loops, best of 3: 200 msec per loop python -m timeit -s "import numpy as np" -s "a = np.array(list(range ...
How can I use numpy.correlate to do autocorrelation?
What you need to do is take the last half of your correlation result, and that should be the autocorrelation you are looking for. A simple python function to do that would be: def autocorr (x): result = numpy.correlate (x, x, mode='full') return result [result.size//2:]
How to get element-wise matrix multiplication (Hadamard …
Oct 14, 2016 · Always use numpy arrays, and not numpy matrices. See what the numpy docs say about this. Also note that from python 3.5+, you can use @ for matrix multiplication with numpy arrays, which means there should be absolutely no good reason to use matrices over arrays. –