Modules is one of the best feature of Python. Except some core modules, you can install what you need and keep your Python setup smooth.
When the next calculation needs an array of zeros that lines up with an array you already have, NumPy can build it for you. np.zeros_like creates that array, copying the shape and data type of the one you give it.…
When you’re about to fill a NumPy array with your own values straight away, you only need NumPy to set aside the space. np.empty creates that array without setting its values, and np.empty_like does the same using another array’s shape…
Data saved as a CSV (comma-separated values) file is plain text until you load it into something Python can work with. pandas read_csv() reads the file into a DataFrame, a table with labeled rows and columns. In this piece, I’ll…
Given a point’s x and y coordinates, you may need the angle it makes with the x-axis. np.arctan2 calculates that angle and uses the signs of both coordinates to put it in the right quadrant. You’ll get the angle in…
Fitting a line to data points means finding the slope and intercept that make the line’s errors as small as possible. SciPy’s minimize function searches for those values, starting from a guess you give it. The example writes the error…
Some scripts need to write data to a file for a short time, such as a step in the middle of a larger job, without keeping it afterwards. Python’s tempfile module creates temporary files and folders with generated names and…
Python lists can hold numbers, but doing math on every element means writing a loop. A NumPy array stores numbers of one type in a grid, so you can calculate on the whole array at once. Here I’ll create arrays…
Scientific calculations in Python, such as estimating an integral or finding a minimum, lead you to SciPy. It’s a free library of numerical algorithms that works on the arrays NumPy provides. I’ll map SciPy’s subpackages to the calculations they handle,…
To find the average of numbers stored in a NumPy array, you don’t need to add them up yourself. np.mean calculates the average of the whole array, or a separate average for each row or column. Here I’ll show both…
The final np.gradient estimate can be negative even when the sample values rise, if the coordinates step backward from 9.0 to 0.1. That negative result makes the role of coordinate order clear to me. Pair each slope with the coordinate…