This web-app is an attempt to allow spreadsheet type calculations
using simple algebraic formulas. A variable corresponds to
a single column in a spreadsheet, and that column can be referred
to by name in other calculations.
The graph allows you to look at covarying relationships between
different variables. The data tables allow you to see the actual
values, along with summary statistics such as the minimum, maximum,
and sum of the data.
The types of data that can be generated are as follows:
- range: A range is a set of data that has a definite first
and last value with equally spaced values. You specify the first
and last values and the number of data points.
- dependent: A dependent variable is calculated as some formula
based on one or more previously defined variables. You actually just
type the formula using the names of other columns. The derivative of a
formula can also be generated using D(formula).
- table: This is for data that is not automatically generated, but
is simply typed directly in. You might use this to import one or more
columns of raw data. The first row defines the names; all remaining rows
provide the data, where the values are separated by white space.
- sequence: A sequence allows you to define a set of values using some
type of recursive formula.
- arithmetic sequence: A sequence with equally spaced values such that
subsequent values are always found by adding some constant number to the
- geometric sequence: A sequence with equally spaced values such that
subsequent values are always found by multiplying some constant number to the
- recursive sequence: A sequence formed by applying any arbitrary function
(based on a formula you type) to the previous value to determine the subsequent
value. Arithmetic sequences use the function f(x)=x+a.
Geometric sequences use the function f(x)=a*x.
- accumulation sequence: A sequence that combines the idea of recursion and dependence on other columns
such that the subsequent value is always the previous value in the sequence plus
some function of other variables. This also allows for relative indexing on those variables.