ODE Solver

An ordinary differential equation or ODE is a differential equation containing a function or functions of one independent variable and its derivatives.
ODE Solver solves systems of ordinary equations with initial boundary conditions with 4th order Runge Kutta Method. It plots and lists results exporting them via email.
All variables, x, u, and t, should be entered with "$" prefix and ODE Solver does the rest.
Example: Typical Pendulum
dx/dt = $u
du/dt= -pi()**2/4*sin($x)-0.1*$u

Following functions are available in ODE Solver:
Operators:
+ add
- subtract
* multiply
/ divide
** pow exponentiation
Functions:
sqrt() - returns the square root of the passed parameter
log() - returns the base 10 log of the passed parameter
ln() - returns the base e log of the passed parameter
exp() - returns e raised to the power of the passed parameter
The trigonometric functions:
dtor() - converts the passed parameter from degrees to radians
rtod() - converts the passed parameter from radians to degrees
sin(), cos(), tan()
Their inverses (asin, acos, atan)
Their reciprocals (csc, sec, cotan)
The reciprocals of the inverses (acsc, asec, acotan)
The hyperbolic variations of all the above functions (sinh, cosh, tanh, asinh, acosh, atanh, csch, sech, cotanh, acsch, asech, acotanh)

Constants:
pi() - returns the value of π.
pi_2() - returns the value of π/2
pi_4() - returns the value of π/4
e() - returns the value of e
Other:
-Entry field background color turns to red color in case of unpaired parentheses and turns to green color once parentheses are paired again.
- Entry field background color turns to red colour in case of unpaired parentheses and turns to green color once parentheses are paired again.
- Recognizing entries with errors and raising warnings.
- Special keypad for formula entries.
- Cursor arrows enables editing entries.