Yes, this is clearly nonsense. Sorting is not a hard problem and standard algorithms such as quicksort and mergesort have O(x^2) and O(n log(n)) complexity. But let me scratch this itch of sorting numbers using an evolutionary algorithm, specifically Covariance…
Create a pandas dataframe with a date column: import pandas as pd import datetime TODAY = datetime.date.today() ONE_WEEK = datetime.timedelta(days=7) ONE_DAY = datetime.timedelta(days=1) df = pd.DataFrame({‘dt’: [TODAY-ONE_WEEK, TODAY-3*ONE_DAY, TODAY], ‘x’: [42, 45,127]}) The dates have gaps: dt x 0 2018-11-19…
Cosine similarity is the normalised dot product between two vectors. I guess it is called “cosine” similarity because the dot product is the product of Euclidean magnitudes of the two vectors and the cosine of the angle between them. If…
Here is the code: %matplotlib inline import geopandas as gpd import matplotlib as mpl # make rcParams available (optional) mpl.rcParams[‘figure.dpi’]= 144 # increase dpi (optional) world = gpd.read_file(gpd.datasets.get_path(“naturalearth_lowres”)) world = world[world.name != ‘Antarctica’] # remove Antarctica (optional) world[‘gdp_per_person’] = world.gdp_md_est…
Step one: brew install glpk pip install pulp Step two: from pulp import * prob = LpProblem(“test1”, LpMinimize) # Variables x = LpVariable(“x”, 0, 4, cat=”Integer”) y = LpVariable(“y”, -1, 1, cat=”Integer”) z = LpVariable(“z”, 0, cat=”Integer”) # Objective prob…
Assume that you have a file with some locations as text with one location per line. For example, here are some school names in Copenhagen, Denmark, stored in schools.csv: Hyltebjerg Skole Heibergskolen Ellebjerg Skole Katrinedals Skole Peder Lykke Skolen Amager…
Python 3.x, and in particular Python 3.5, natively supports asynchronous programming. While asynchronous code can be harder to read than synchronous code, there are many use cases were the added complexity is worthwhile. One such examples is to execute a…
Whenever two things have a directional relationship to each other, then you can compute the pagerank of those things. For example, you can observe a directional relationships between web pages that link to each other, scientists that cite each other,…
I like to code in Python. I also like the concept of asynchronous workers to build loosely coupled applications. Luckily, RabbitMQ and Celery can help me do exactly that. This post is based on a very nice YouTube video by…
Pandas and SQLAlchemy offer powerful conversions between CSV files and tables in databases. Here is a small example: import pandas as pd from sqlalchemy import create_engine df = pd.read_csv(‘mydata.csv’) engine = create_engine(”) df.to_sql(‘mytable’, engine) Read more: pandas.DataFrame.to_sql sqlalchemy engines