Getting Started
ODCalc is a calculator which makes it easy to use information from open data sources such as Wikipedia in your calculations. It also supports conversion of arbitrary units throughout giving the results in normal scientific unit for the quantity. It is also a pretty good general calculator for engineering, science and other fields.
Some of the core features are
- Pulls in open data and scientific constants from sources such as Wikipedia and NIST
- Conversion and simplification of units including live currency rates
- Calculations with all the normal mathematical operators
- Full support for complex numbers
- Vector calculations and (some) matrix operations
- Logical expressions and logical indexing
- Comprehensive set of maths functions (trigonometry, logs, arithmetic...)
- Workspace with variables
Simple Calculations
ODCalc is a calculator
Other operators and brackets work like they do in other computer applications such as Excel, C, Java, MATLAB
The normal maths functions exist
as do trigonometry functions – note the use of deg for specifying an input in units of degrees
Complex numbers are supported using i
and different counting bases using prefixes, for example 10 in hexadecimal plus 10 in decimal displayed in binary
Units
The calculator understands and is able to convert between a large number of units
and will automatically convert between units when numbers are used in calculations
It will also track when units are multiplied, divided, etc. resulting in quantities in different units
and in many cases can simplify the resulting units
Units can be entered using their names or symbols with or without engineering prefixes so all entries in the following array are equivalent
Currencies are supported in the same way as other units with current conversion ratios pulled from the internet
Currency symbols and finance style scale factors can also be used
The above expression was ambiguous because many currencies use the $ symbol. When an expression is ambiguous this is indicated next to the result and the user interface allows selection of the correct option. The system tries to offer the most likely option first, for example in the previous case the $ was interpreted as United States dollars – it is normally possible to customise which is offered first from user interface. In the above calculation we really wanted Jamaican dollars which can be selected to give:
The calculator can convert between arbitrary combinations of units involving currencies or anything else
Open Data
ODCalc was designed to provide convenient access to open data for use in calculations. There are a few sources available but Wikipedia is currently the most developed. Wikipedia is a property data source in that it provides properties of things using the of keyword:
The software is able to automatically read the values that appear in the infoboxes on many Wikipedia pages. These properties can then be used in calculations. For example what is the population of the Benelux bloc as a proportion of the whole European Union?
What is the weight (mass) of a small glass of vodka?
What is the resistance of 10 metres of 2.5mm2 cross section copper wire?