Categories
Development

Map(), lambda() functions for 2-d arrays

Suppose we’ve a following array:

arr = [[ 5.60241616e+02,  1.01946349e+03,  8.61527813e+01],
 [ 4.10969632e+02 , 9.77019409e+02 , -5.34489688e+01],
 [ 6.10031512e+02, 9.10689615e+01, 1.45066095e+02 ]]

How to print it with rounded elements using map() and lamba() functions?

l = list(map(lambda i: list(map(lambda j: round(j, 2), i)), arr))
print(l)

The result will be the following:

[[560.24, 1019.46, 86.15], 
 [410.97, 977.02, -53.45], 
 [610.03, 91.07, 145.07]]
Categories
Data Mining

Sklearn, Classification and Regression metrics

in the post will reviewed a number of metrics for evaluating classification and regression models. For that we use the functions we use of the sklearn library. We’ll learn how to generate model data and how to train linear models and evaluate their quality.

The code as an IPython notebook

Categories
Data Mining

Linear models, Sklearn.linear_model, Regression

In this post we’ll show how to build regression linear models using the sklearn.linear.model module.

See also the post on classification linear models using the sklearn.linear.model module.

The code as an IPython notebook

Categories
Data Mining Development

Linear models, Sklearn.linear_model, Classification

In this post we’ll show how to build classification linear models using the sklearn.linear.model module.

The code as an IPython notebook

Categories
Data Mining

Cross-validation strategies and their application

In the post we’ll get to know the Cross-validation strategies as from the Sklearn module. We’ll show the methods of how to perform  k-fold cross-validation. All the iPython notebook code is correct for Python 3.6.

The iPython notebook code

Categories
Data Mining Development

Work with inbuilt datasets of Sklearn and Seaborn libraries

In the post we will show how to generate model data and load standard datasets using the sklearn datasets module. We use sklearn.datasets in the Python 3.

The code of an iPython notebook

Categories
Data Mining

Linear regression and Stochastic Gradient Descent

In this post we’ll show how to make a linear regression model for a data set and perform a stochastic gradient descent in order to optimize the model parameters. As in a previous post we’ll calculate MSE (Mean squared error) and minimize it.

Categories
Data Mining

Linear Regression application for data analysis and scientific computing

In this post we’ll share with you the vivid yet simple application of the Linear regression methods. We’ll be using the example of predicting a person’s height based on their weight. There you’ll see what kind of math is behind this. We will also introduce you to the basic Python libraries needed to work in the Data Analysis.

The iPython notebook code

Categories
Data Mining

Weibull distribution & sample averages approximation using Python and scipy

In this post we share how to plot distribution histogram for the Weibull ditribution and the distribution of sample averages as approximated by the Normal (Gaussian) distribution. We’ll show how the approximation accuracy changes with samples volume increase.

One may get the full .ipynb file here.

Categories
Data Mining

Simple text analysis with Python

Finding the most similar sentence(s) to a given sentence in a text in less than 40 lines of code 🙂