How To ← Winwaed Blog ← Page 2

Beware of Choropleth Maps!

Nov

12

2018

I was recently experimenting with the new Maptitude data of 2018 Zip Code Business Counts. Free for existing customers, this data lists the total number of businesses by type (NAICS code) for every zip code in the USA. This data represents a huge number of data fields, and it is recommended that users read Caliper’s ...

Drawing SVG Superellipses with Python

Jun

15

2018

Superellipses are a little bit of a mathematical oddity, resembling rounded squares or square-ish circles. They are, however, becoming popular for icon outlines. iOS currently uses them, as do recent versions of Android. This article shows you how to use Python to create an arbitrary superellipse in SVG. This can then be used as an ...

Close all Views with GISDK

Aug

12

2016

Thanks to Paul Lucassen and Stewart Berry, here is a short piece of GISDK macro code to close all Data View windows: {window_list} = GetWindows("Editor") for i = 1 to window_list.length do CloseEditor(window_list[i]) end To use this code, open the Immediate Execution window in Maptitude (far right button on the GISDK Toolbox with the lightning ...

Plotting Place Names from Natural Text in Python 3

Jul

13

2016

This example uses Maptitude’s new Python 3 interface to draw annotation on a map. The annotation is in the form of place names mentioned in H.G. Wells’ War of the Worlds. This also serves as a basic demonstration of using NLTK (Natural Language Toolkit) to identify named entities (proper nouns) in the book text. Annotation ...

Using Python to Filter and Correct Data

Jun

13

2016

This example uses a Python script to create a new layer within Maptitude from an input file of Oklahoma well injection data. The input data has a number of erroneous coordinates, so the script filters the bad coordinates out. A few of these coordinates have incorrect signs (e.g. negative latitude or positive longitude), so these ...

Mapping Earthquakes

Jun

13

2016

Maptitude can also be used plot earthquakes, examine patterns in earthquakes, and even look for correlations with other factors such as oil industry activity. Earthquake catalogs from recent years can be downloaded from the US Geological Survey at http://earthquake.usgs.gov/earthquakes/search/ . For the following maps, the data is downloaded as a CSV (comma separated value) file, ...

Why is it important to practice defensive driving, and how can it benefit

Feb

18

2016

Why is it important to practice defensive driving, and how can it benefit Defensive driving is the technique in which you drive cautiously and smoothly, minimising the chances of engaging in an accident and damaging your car and that of third parties. Car accidents mainly occur due to reckless and rash driving. A defensive driver ...

NLTK on the Raspberry PI

Aug

24

2012

If you haven’t heard of it yet, the Raspberry Pi is a $25/$35 barebones computer intended to excite kids with programming and hardware projects. It is very much modeled on the British experience of home computing in the early 1980s and even has a “Model A” and a “Model B” in homage to the BBC ...

Sentence Segmentation: Handling multiple punctuation characters

Jun

13

2012

Previously, I showed you how to segment words and sentences whilst also taking into account full stops (periods) and abbreviations. The problem with this implementation is that it is easily confused by contiguous punctuation characters. For example “).” is not recognized as the end of a sentence. This article shows you how to correct this.

Using BerkeleyDB to Create a Large N-gram Table

May

17

2012

Previously, I showed you how to create N-Gram frequency tables from large text datasets. Unfortunately, when used on very large datasets such as the English language Wikipedia and Gutenberg corpora, memory limitations limited these scripts to unigrams. Here, I show you how to use the BerkeleyDB database to create N-gram tables of these large datasets.