A 2D simple regression analysis.

Making Math Less Stressful With A Python Super-Calculator

In a recent write-up, [David Delony] explains how he built a Wolfram Mathematica-like engine with Python.

Core to the system is SymPy for symbolic math support. [David] said being able to work with symbolic math easily has helped his understanding of calculus and linear algebra. For statistics support he includes NumPy, pandas, and SciPy. NumPy is useful for creating multidimensional arrays and supports basic descriptive statistics such as mean, median, and standard deviation; pandas is a library for operating on tabular data arranged into “DataFrames”, it can load data from spreadsheets (including Excel) and relational databases; and SciPy is a “grab bag” of operations designed for scientific computing, it includes some useful statistics operations, including common probability distributions, such as the binomial, normal, and Student’s t-distribution.

For regression analysis [David] includes statsmodels and Pingouin. If you’re not familiar with the term “regression analysis” it basically refers to the process of curve fitting. When your data is two-dimensional, with one dependent variable, the simple linear regression algorithm will generate a function that fits the data as y = mx + b, including the slope (m) and the y-intercept (b); this can be extrapolated to higher dimensional data and other types of regression.

If you have an interest in symbolic math you might enjoy learning about Mathematica And Wolfram On The Raspberry Pi.

Photoresistor-based Single Pixel Camera

[Hugh] has been going back through episodes of the Hackaday podcast, and Elliot mentioned in episode 67 that it can often be inspiring to go back through the archives of Hackaday to find ideas for new projects. Well, he did just that and came across a single-pixel camera made using an infrared photodiode. He decided to try and hack together his own single-pixel camera, but this time on the cheap and using an ever simpler component – a photoresistor!

His description of the project tickled me – “I’ve used an ESP32, MicroPython, two servos, a peanut butter jar lid, a toilet paper roll, a paper towel roll, magnets and scrap wood for this version.” That’s certainly a much simpler bill of materials than the original (which was written up by Hackaday way back in 2015), which used a nice metal frame to hold everything together. However, there’s absolutely nothing wrong with improvising with things you happen to have to hand.

Continue reading “Photoresistor-based Single Pixel Camera”

D-POINT: A Digital Pen With Optical-Inertial Tracking

[Jcparkyn] clearly had an interesting topic for their thesis project, and was conscientious enough to write up a chunk of it and release it to the wild. The project in question is a digital pen that uses some neat sensor fusion to combine the inputs from a pen-mounted gyro/accelerometer with data from an optical tracking system provided by an off-the-shelf webcam.

A six degrees of freedom (6DOF) tracking system is achieved as a result, with the pen-mounted hardware tracking orientation and the webcam tracking the 3D position. The pen itself is quite neat, with an ALPS/Alpine HSFPAR003A load sensor measuring the contact pressure transmitted to it from the stylus tip. A Seeed Xaio nRF52840 sense is on duty for Bluetooth and hosting the needed IMU. This handy little module deals with all the details needed for such a high-integration project and even manages the charging of a single 10440 lithium cell via a USB-C connector.

Positional tracking uses Visual Pose Estimation (VPE) assisted with ArUco markers mounted on the end of the