## Saturday, 9 March 2013

### Introducing the iOS app SciStatCalc

Welcome to the support page for the iOS app SciStatCalc. The portrait mode operation is a Scientific Calculator, a screenshot of which is displayed below. There are five segments.

The mathematical function buttons are colour coded - the inverse counterpart to a function is red, while the function itself is blue. Functions and corresponding inverses occur on the same display.

The following functions are supported: sin, cos, tan, arcsin, arccos, arctan, square root, square, sinh, cosh, tanh, arcsinh, arccosh, arctanh, cube root, cube, $x^y$, $log_yx$ ,$10^x$, $log_ex$, $e^x$, $nPr$, $nCr$, $1/x$, $\Gamma(x)$, error function, inverse error function, lower and upper normalised incomplete gamma functions $P(a,x)$ and $Q(a,x)$. For the trigonometric functions, you can select between degrees and radians. There is also an $lcm$ (least common multiple) and a $gcd$ (greatest common divisor) function.

In the last segment, there is a number stack system, where you can push numbers and pop numbers off a stack, clear the entire stack, calculate the sum, average and the standard deviation of the numbers within the stack.

When the device is oriented in landscape mode, ensuring that the Home button is on the left, a CDF/inverse-CDF Calculator is displayed. In this mode, swiping left/right results in a different distribution being displayed. Two out of the three fields (Upper Limit,  Lower Limit, Probability) must be filled in, as do all the settable parameter fields - pressing the Calculate button results in the single missing field being updated with the result. When filling in the lower/upper limit, you can enter -inf or inf for minus/plus infinity respectively - of course, the ranges will only be valid for the support of the particular distribution. Screenshots occur below.

The following distributions are supported:-
1. Beta
2. Binomial
3. Cauchy-Lorentz
4. Chi-squared
5. Exponential
6. F-distribution
7. Gamma (two parameterisations)
8. Gaussian
9. Geometric
10. Laplace
11. Logistic
12. Log-Normal
13. Pascal
14. Poisson
15. Rayleigh
16. Student-t
17. Weibull
Staying in landscape mode, if you swipe up, you obtain a statistical tests calculator, which includes the following:

1. Unpaired Student's t-test
2. Paired Student's t-test
3. Small sample hypothesis test
4. Chi-squared test
5. Uniform Random Number Generator

In this mode, swiping left/right will select one of the statistical tests. To revert back to the CDF/inverse-CDF calculator, simply swipe down. Some screenshots occur below.

Orienting the device in Portrait mode will bring back the Scientific Calculator.

In Portrait mode, you can copy the number displayed by swiping LEFT resulting in the following display, in order to paste to a textfield in the landscape StatsCalc (swiping right while entering a number will erase the last digit..)

Orienting the device in landscape mode, you simply paste following the usual way.

To paste from landscape to portrait mode, once in portrait mode, pan with two fingers on the display.

You can purchase the App from the App Store.