Questions tagged [numpy]
NumPy is one of the fundamental packages used for scientific computing in the Python ecosystem. Specifically, NumPy is used for numerical computing and uses n-dimensional arrays.
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How to solve a non-linear system, in Python, with the GAUSS-NEWTON algorithm? (Jacobian matrix J, etc.)
I would like to solve a non-linear system (which contains the goals of a football team in previous matches) using the Gauss-Netwon algorithm, in order to find the parameter (of frequency) to use as ...
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Python Implementation of ODE for matrix operations
I am trying to develop a model and I am stuck as to how this should be implemented in python using ODE. My entire population is divided into regions and part of the model takes this into consideration ...
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Keras Model Produces Different Outputs, But Outputs Map To The Same Vector
I have a neural network that produces output vectors from input vectors. These output vectors are different depending on what input vector it is being asked to predict for. I have a dictionary that ...
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Data Skewness is nan or inf
I have checked the Skewness of my data before applying a Log transformation using the next code :
print("Skewness: %f" % df['Wind Speed (km/h)'].skew())
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Array column in dataframe as input for classification models
Please consider the following dataframe:
My challenge is with the column 'geometry_coordnates'.
I've got a column 'geometry_coordnates' that is an array of numbers. It can be a representation of a ...
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df['col'] refactoring
I made a big mistake by using df.iterrows() in a computationally heavy project. Now I need to convert it to np loop and need to rename all df['col'] occurrences to np[i]. How can I do it not manually, ...
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Batch processing for a dictionary of dictionaries Python
I have a very large dictionary of the form vf = {key1:{...}, key2:{...}, key3:{...}, ...}, which is stored as an npz file. Trying to load it at once causes a memory error, so I tried to load it in ...
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Remove outlier from image array in Python
Could someone please suggest me what would be the best way to remove such huge number of outlier data from the image. The regular clipping between data range in numpy array would simply reduce the ...
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why np.cos returns erroneous values?
I'm debugging my python program.
I have np.cos(param_t_10[0]) returns 5.9168e-06 where ...
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How to deal with "Could not broadcast input array from shape (1141,2) into shape (1141,)" to get Out-of-Bag error while using Random Forest
I have a dataset that consists of 171 features and 39 labels. I captured both features and labels of the dataset through slicing:
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Trying to write a code that detects a maximum value before a drop off in slope
I'm trying to write code for a force test that will output the maximum force before structural failure occurs. I'm a bit of a novice to python, so the issue here might be something simple that I'm ...
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Why most keras examples use shape=(None,) instead of shape=(None)?
I'm reading several keras tutorials and found that many examples are written like this:
keras.Input(shape=(None,), dtype="int64", name="english")...
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What is numpy.dot(a, b)[i,j,k,m] = sum(a[i,j,:] * b[k,:,m]) in numpy.dot() documentation?
I was trying to understand difference between np.dot and np.matmul and in the docs of np.dot() there is this code
dot(a, b)[i,j,k,m] = sum(a[i,j,:] * b[k,:,m]). ...
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How to solve MemoryError problem?
I have audio signals which I need to convert them to melspectrogram. I am using Deepfilternet to remove background noise. when I use the output of Deepfilternet for next phase like padding, it showed ...
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Perform k-means clustering over multiple columns using python but without library sklearn.kmeans
I'm on a project with the topic "clustering" using the KMeans method.
so I have a data set with 10 columns and 1000 rows divided into 5 clusters (in this case there are 5 robot movements). I'...
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Speaker Verification with TRILLsson
I am searching for models suitable for Speaker Verification. I stumbled across the TRILLsson models. It seems to be usable for Speaker Verification, but i haven't managed to make it work yet.
I tried ...
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Why the numbers 6 and 8 not selected when indexing this numpy array?
In the below code why the numbers 6 and 8 not selected?
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ValueError: Failed to convert a NumPy array to a Tensor (Unsupported object type int) in Python - from_gerator fails
I know this question has answers, but they are not working.
why this fails ?
(and why tensorflow has troubles in reading numpy!!)
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How do I represent multiple seconds of video in tensors?
I want to use ResNet-18 for image features at the head of a VAE. If I have 10 seconds of video at 30 frames per second, and if ResNet-18 gives me the features of a single frame as a 512-dimensional ...
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Counting values from diffrent columns
I'm working with a pandas dataframe that has some columns like these:
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OpenCV add/subtract functions produce different results from numpy array add/subtract
Im trying to brighten and dim an image using OpenCV with two approaches.
Approach 1: Used OpenCV's add and subtract functions to ...
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Unsupported object type int Error where array is already in float32
I am learning DL. For the following dataset:: spam.csv can be found here::Click here to see. I am trying to implement a simple NN to detect spam email. For the following code::
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Pandas filtering with np.where as filter not working as expected
working on Kaggle's SpaceShip Titanic dataset and I was doing some analysis of the data.
Call tt the pd.DataFrame containing the ...
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How to change the color of sock images while preserving their natural texture?
In our company, we have a large number of sock images that we need to modify. We want to change the color of specific parts of the sock image, while preserving the natural texture of the socks. We're ...
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How can I convert a numpy array of tensors to tensor of tensors?
It is my first GRU model so pardon the stupidity. I am trying to learn by training a simple GRU network on variable length sequences. The sequences are numpy arrays of tensors. The length of numpy ...
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Large Numpy array causes error when trying to load
I'm making an ai using image recognition, so I recorded each frames of me playing into a numpy array. It worked just fine when the first time I exported all the images and got the 6 thousand of them. ...
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EagerTensor object has no attribute 'astype'
I am using trained tf model output (TF 2.8) and trying to convert it to numpy array.
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problem on converting data to numpy array
I have pandas data frame
data=df.loc[[0]]
print(data)
0 3.5257,3.5257,3.5257000000000005,3.5257,3.5257...
Name: testdata, dtype: object
I need to convert it to ...
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Change the shape of numpy array
My numpy array has the shape of (99,2) basically it has 2 columns one is the word and the other is a hot encoding vector size of 300 I want to delete the column of words and want to have only encoding ...
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Get the value of second dimension in numpy array
My NumPy array looks like this
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Looking for Exercises/labs
If someone knows some labs/exercises where you can train Pandas, numpy, seaborn.
I appreciated! I have being looking on Kanggle, but if you guys know other options please let a comment
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numpy power function output for 2 to the power 63
I am running some test code and observed something strange. the numpy power function giving strange output post 2 to the power 62
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Using python AI mnist to recognize my picture, trained accuracy is 97.99%, but accuracy to my img is less than 20%
Questions like these are difficult to debug, but you'll hopefully find more help on datascience.stackexchange.com than here
I see the suggestion that post in Data science is also a good option
Using ...
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Binary classification works with softmax, but not sigmoid
I am doing a binary classification problem for seizure classification. I split the data into Training, Validation and Test with the following sizes and shapes
dataset_X = ...
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Error using sigmoid activation function in the last dense layer of a LSTN
Trying to use sigmoid as an activation function for the last dense layer of a LSTN, I get this error
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How can i get this way to create random data?
I need to create random data using this lines
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Is it advisable to save an ML model as a Joblib/Pickle file?
Part of our thesis project is to create a Diabetes predictor web application, and I have something I like to clarify. Is it a common practice to save an ML model as a Joblib/Pickle file like this one? ...
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Creating a scatter plot with matplotlib with large dataset
I am trying to create a scatter plot from instrument peak area data recorded every tenth of a second or so. For some reason, when I try to plot it with Matplotlib, I get a straight line, which is not ...
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How to convert Torchvision image tensor to base64 directly?
I have this code that is supposed to convert an image entry of a Torchvision dataset to a base64 string. To do that, it serializes the tensor from a Torchvision dataset to a string, modifies that ...
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How to convert postgresql tabular data to a numpy array?
I'm completely new to data science and I have a problem that I need help in resolving. I have time series data (with 87 million rows currently, though that will grow) with x, y coordinates, a ...
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Why normalized eigen values and eigen vectors can have imaginary number?
My goal is to prove why normalized eigen values and eigen vectors have imaginary number.
According to this website: normalized eigen vector is just ...
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Applyingv a 2D mask onto a 3D rgb color list
Problem
I have the following image data as a 3D numpy array containing rgb values of the image in a (n,n,3) shaped list (Image). I also have data of the corresponding black and white mask image in a (...
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y_true takes value in {} and pos_label is not specified: either make y_true take value in {0, 1} or {-1, 1} or pass pos_label explicitly
I want to run "4_forgery_detection_result.ipynb" from an available code. In this cell of the code,
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Overflow encountered in matmul while doing forward propagation
I wrote this code to do forward propagation
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logistic regression,machine learning
I just started learning ML, so I tried to implement logistic regression on my own in 2 ways (the first code and the second code), but they aren't working, I cross-checked by using sklearn (third code ...
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Creating a grid type 3D data array from data points [closed]
I have a 3 data column $(X, Y, Z)$ ranges from $(min, max)$. For example,
$X = (0, 5)$, $Y=(0, 3)$, $Z=(0, 2)$. By using them I need to create a numpy array in the form of
$[(0, 0, 0), (0, 0, 1), (0, ...
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How to solve this ValueError: Dimensions must be equal
I'm trying to train an autoencoder model with colored image samples but I got this error
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How to solve MemoryError problem
I've created and normalized my colored image dataset of 3716 sample and size 493*491 as x_train, its type is list
I'm tring to convert it into numpy array as follows
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Python: calculate the weighted average correlation coefficient
I am calculating the volatility (standard deviation) of returns of a portfolio of assets using the variance-covariance approach. Correlation coefficients and asset volatilities have been estimated ...
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