FormulaCalculatorPro — User Manual

Write a formula once and calculate it as often as you like — with variables, multiple lines, loops, mathematical functions and physical constants. Plus a Quick Calculator for anything you only need to work out once. This manual describes everything the app can do, in the order you usually need it.

1 — First launch

The window has two parts: the sidebar on the left, the workspace on the right.

On first launch FormulaCalculatorPro creates about 50 example formulas in nine categories — from compound interest to circle area to an amortization schedule. They are a good way to get to know the app and can be changed or deleted like your own formulas.

At the bottom of the sidebar:

The symbol at the top next to the window buttons hides and shows the sidebar.

2 — Finding and organizing formulas

Groups in the sidebar

Favorites

Formulas you have marked with the star.

All Formulas

Every formula, regardless of category.

Category

Below it the individual categories, each with its number of formulas.

Tiles or list

Two symbols at the top right above the formulas switch between tiles and a list. Each tile shows name, description, the beginning of the formula, the number of variables and when the formula was last changed. The loop symbol in the top right corner marks a loop formula.

Searching

The Search formulas… field searches name, description and formula text of the group shown. Upper and lower case don't matter.

Favorites

Clicking the star on a tile adds the formula to Favorites or removes it. The context menu does the same.

The context menu

Right-clicking a formula offers:

• Edit — opens the editor.
• Add to Favorites or Remove from Favorites.
• Duplicate Formula — asks for a name for the copy.
• Rename.
• Delete — with confirmation.

3 — Calculating a formula

Clicking a formula opens it. At the top are name, description and the formula text; below, the variables on the left and the calculation steps on the right.

Entering values

Each variable has four fields:

The values are saved with the formula and are there again the next time you open it.

Calculating

The Calculate button at the top right runs the formula with the values entered. The results then appear on the right.

Display mode: Steps or Result

Steps

Every calculation step on its own: which line, which expression, which result and how long it took. For loops the iteration is shown as well.

Result

Only the final state of all variables after the calculation, each on its own card with its current and original value.

With a very large number of steps a note recommends the “Result” mode. A loop with hundreds of iterations otherwise produces a very long list.

Passing results on

• The copy symbol on a card or step puts that one value or step on the clipboard.
• The share symbol to the left of Calculate offers Copy All Results, Copy All Steps and Export Results.

Very large and very small numbers

From one trillion upwards and below 0.0001, FormulaCalculatorPro shows results in scientific notation, for example 6.674e-11. That way no precision is lost in the display for such magnitudes.

At the bottom of the window

Edit, Rename, Duplicate and Delete act on the open formula.

4 — Writing formulas

The editor

The formula is checked as you type. An error turns the formula field red and states the reason. Save saves; Cancel discards the changes.

Syntax

Write decimal numbers with a point: 3.5.

Multi-line formulas

A formula may consist of many lines. Each line is an assignment or an expression, and later lines can use the results of earlier ones:

# Annuity loan, monthly payment
MonthlyInterest = AnnualInterest / 12 / 100
NumberOfMonths = LoanTerm * 12
q = 1 + MonthlyInterest
Payment = LoanAmount * MonthlyInterest * pow(q, NumberOfMonths) / (pow(q, NumberOfMonths) - 1)

Here AnnualInterest, LoanTerm and LoanAmount are the inputs; everything else is calculated.

Variables

You don't need to create variables. FormulaCalculatorPro detects them as you write. Names follow these rules:

• Letters, digits and the underscore are allowed: InitialCapital, v_end, x2.
• No hyphen and no space. interest-rate is read as “interest minus rate”.
• Easiest to read are names written together with capital initials: MonthlyPayment.

The result variable

The variable calculated in the last calculation line is the result variable. It is highlighted in the formula view.

It also appears in the list of variables, with the value 0. There you can set its decimal places and unit. So every calculation starts from scratch.

5 — Functions and constants

In the formula field, functions appear in blue and constants in yellow. The Functions and Constants buttons above the formula field each open a window with all available entries. The plus next to an entry inserts it at the cursor.

log(x) calculates to base 10, log(b, x) to base b. The natural logarithm is ln.

If a value is outside what a function accepts — such as the square root of a negative number or the logarithm of zero — the calculation stops with a message that states the permitted range.

Constants

More than 50 constants are available, from the speed of light c and standard gravity g to the density of water rho_water. Many have two spellings, such as π and pi or ε_0 and eps0. The window shows the value and unit of each constant.

6 — The Formula Assistant

The Assistant button above the formula field opens a reference window with four tabs: Operators, Constants, Functions and Tips. The search field at the top searches all four at once.

7 — Loops

A loop repeats part of the formula until a condition is met. This lets you add up interest month by month, pay off a loan down to the last installment, or refine an approximation until it is precise enough.

Turn it on with the Loop Formula switch in the editor. The Loop tab then appears.

Basic Loop

Extended Loop

The Extended Loop is a second loop around the Basic Loop. It can only be selected once the Basic Loop is filled in completely. It has its own lines, its own maximum and up to five conditions.

• Each condition consists of a variable, a comparison and a target value. All six comparisons are available here: >=, <=, ==, !=, > and <.
• AND (all must be met) or OR (at least one must be met) links the conditions.
• Individual conditions can be switched off temporarily with Active without deleting them.

How a loop runs

1. First the whole formula is calculated once from top to bottom.
2. If the condition is not yet met, the range of the Basic Loop is repeated until it is, or until the maximum is reached.
3. Then the lines after the loop are calculated.

With the Extended Loop, the Basic Loop runs inside and the Extended Loop outside: after each complete run of the Basic Loop its monitored variable is set to 0, the lines of the Extended Loop follow once, and then its conditions are checked. That gives, for example, a savings plan that counts twelve months inside and the years outside.

8 — The Quick Calculator

For a calculation you don't want to save as a formula. The Quick Calculator button at the bottom of the sidebar opens it.

• The result appears while you type, as soon as the calculation is complete.
• If the calculation contains a name that is not a constant, it appears on the left as a variable with an input field.
• Functions and constants work here just as in formulas.
• The Quick Calculator does not accept assignments with =. If you need intermediate results, create a formula.

The history keeps the last ten calculations, even after quitting the app. Clicking an entry loads the calculation and its values again.

When speech control is on, a microphone appears at the bottom left. With it you can speak the calculation, such as “five times three plus two”.

9 — Categories

The Category button at the bottom of the sidebar opens Manage Categories.

• The plus at the top right creates a new category.
• Each category has a name, description, a symbol and a color. The color can also be entered as a hex code.
• The arrows at the top right sort by name, by order or by number of formulas, and show or hide active and inactive categories.
• The menu above the edit area and the list's context menu offer Edit, Duplicate, Deactivate or Activate, and Delete.
• Back at the bottom right returns to the formulas.

10 — Speech control

Formulas can also be calculated by voice. Speech control is off at first and is turned on under Settings › Speech. A short setup then leads through three steps: permission for speech recognition, a microphone test and a test of the speech output.

Afterwards a microphone appears at the bottom of the sidebar. It opens the speech control window:

• “Calculate” followed by the name of a formula starts it. FormulaCalculatorPro then asks for the values of the variables one after the other.
• “Show formulas” lists the available formulas.
• When Enable speech output is on, the result is read aloud.

Speech recognition understands German, English, Italian, Spanish and Dutch, always in the language the app is set to.

11 — Backup

A backup contains all formulas, categories and settings.

Automatic Backup

With Enable Automatic Backup, FormulaCalculatorPro backs up on its own — daily, weekly or monthly. Below it the last and next backup are shown.

Manual Backup

Create Backup saves immediately to a file at a location you choose. Restore Backup brings such a file back.

Management

Backup Retention (Days) sets how long automatic backups are kept: 3 to 15 days. Clean Up Old Backups removes older ones immediately, Open Backup Folder shows them in the Finder.

12 — Export and import

Unlike a backup, exports are meant for passing on — to another Mac, a colleague or a spreadsheet.

• Export All Data writes formulas and categories, Categories Only just the categories.
• Import File reads an exported file. FormulaCalculatorPro asks for confirmation first.
• Under Options you choose whether categories, formulas or both are imported, and whether existing entries are overwritten.

13 — Settings

The gear at the bottom of the sidebar opens the settings. Back returns to the formulas.

14 — Trial and full version

FormulaCalculatorPro is a free download from the App Store and can be tried without restrictions for 7 days. The bottom of the sidebar shows how many days are left.

After that the full version is bought with a one-time in-app purchase, with no subscription. Without a purchase, once the trial has ended no new formulas can be created, no formulas can be calculated and the Quick Calculator cannot be opened. Your formulas are kept.

You buy with Upgrade to full version in the sidebar or under Settings › Purchase. On another Mac with the same Apple ID, Restore Purchase there is enough.

15 — Frequently asked questions

My variable gets no input field.

Then the name is a constant, such as c, e or g. Rename the variable. See Variables.

sin(90) does not give 1.

The trigonometric functions work in radians. Write sin(90 * deg_to_rad).

A hyphen in a name gives a wrong result.

The hyphen is a minus sign. interest-rate calculates “interest minus rate”. Write InterestRate or interest_rate.

The loop doesn't stop where I expect.

In the “Steps” display mode, check how the monitored variable changes from pass to pass. If it never reaches the target value, the loop only ends at the maximum.

The Quick Calculator reports an error at =.

Assignments are not allowed in the Quick Calculator. Write only the expression, or create a formula.

The example formulas are in a different language.

They were created in the language set on first launch. Switching the language only changes the interface.

How do I get the “What's New” window back?

Under Settings › About.