Dalasoft Limited

TimeMoney Manual

Back to TimeMoney Help Screen

Contents

To Top

Overview

TimeMoney performs computations involving Time and Money (or any other entity changing in time as a result of continuous or periodic growth). Accumulation can be simple or compound at different periods, and payments can be made at start or end of period. In addition to the results of computations, tabular schedules show the details of changes over the period of time and, and graphs help to visualize the process.

The custom data entry keyboard, optimized for money entries, is also a calculator with growth-related functions and persistent memory. This allows to perform any additional calculations on the data used.

Current computation is saved when the application is closed. In addition computations can be named, saved and loaded as required, and data can be exchanged between computations through the persistent calculator memory.

To Top

Principles of Operation

To edit or enter a value tap a white entry field. To perform a computation tap a button. To change the compounding or payments settings, tap the required switch button. Tapping a Time button brings up the standard iPhone Date Picker. Tapping a Money button brings up the custom Data Entry Keyboard/Calculator. All entries are preserved until changed, and need not be changed if contain the required values.

To Top

Common Computations Examples

1. Number of years, months, and days between two dates,

Action Button or Label Field Note
Enter Start 3 October 2009 To enter tap the Start Button or the Entry Field
Enter End 28 September 2029 To enter tap the Start Button or the Entry Field
  Years: 20.00 Read the Result
  Months: 240.00 Read the Result
  Days: 7300.00 Read the Result

To Top

2. Date a number years, months, or days after the Start Date,

Action Button or Label Field Note
Enter Start 3 October 2009 To enter tap the Start Button or the Entry Field
  End 28 September 2029 Read the Result
Enter Years: 20.00 To enter tap the Entry Field
  Months: 240.00 Read the Result
  Days: 7300.00 Read the Result

To Top

3. Amount on a deposit account of 1000.00 after 5 years at 4% p.a.

Action Button or Label Field Note
Enter Start 3 October 2009 To enter tap the Start Button or the Entry Field
  End 2 October 2014 Read the Result
Enter Years: 5.00 To enter tap the Entry Field
  Months: 60.00 Read the Result
  Days: 1825.00 Read the Result
Select Year   Interest added yearly
Select Comp   Compound Interest
Select Arr   Payments in Arrears (at end of period)
Enter I% 4.0000 To enter tap the Entry Field
Enter PMT 0.00 Must be 0.00
Enter PV 1,000.00 To enter tap the Entry Field
Tap button FV 1,216.65 Read the Result
Tap button ? Schedule View the Schedule
Tap button ? Graph View the Graph

To Top

4. Monthly payment for a loan (or mortgage) of 100,000.00 for 15 years at 4% p.a. and the total interest paid, total amount paid.

Action Button or Label Field Note
Enter Start 3 October 2009 To enter tap the Start Button or the Entry Field
  End 29 September 2024 Read the Result
Enter Years: 15.00 To enter tap the Entry Field
  Months: 180.00 Read the Result
  Days: 5475.00 Read the Result
Select Month   Payments made and interest added monthly
Select Comp   Compound Interest
Select Arr   Payments in Arrears (at end of period)
Enter I% 4.0000 To enter tap the Entry Field
Enter PMT 739.69 To enter tap the Entry Field
Enter PV 100,000.00 To enter tap the Entry Field
Enter FV 0.00 Must be 0.00
Tap button ? Schedule View the Schedule
Tap button ? Graph View the Graph

To Top

5. The present cost of an annuity yielding 500.00 per month for 10 years at 4% p.a.

Action Button or Label Field Note
Enter Start 3 October 2009 To enter tap the Start Button or the Entry Field
  End 1 October 2019 Read the Result
Enter Years: 10.00 To enter tap the Entry Field
  Months: 120.00 Read the Result
  Days: 3650.00 Read the Result
Select Month   Payments made and interest added monthly
Select Comp   Compound Interest
Select Arr   Payments in Arrears (at end of period)
Enter I% 4.0000 To enter tap the Entry Field
Enter PMT 500.00 To enter tap the Entry Field
Tap button PV 49,385.09 Read the Result
Enter FV 0.00 Must be 0.00
Tap button ? Schedule View the Schedule
Tap button ? Graph View the Graph

To Top

6. Amount of weekly payment (at start of week) required to accumulate 10.000.00 in 5 years at 4%p.a.

Action Button or Label Field Note
Enter Start 3 October 2009 To enter tap the Start Button or the Entry Field
  End 2 October 2014 Read the Result
Enter Years: 5.00 To enter tap the Entry Field
  Months: 60.00 Read the Result
  Days: 1825.00 Read the Result
Select Week   Payments made and interest added weekly
Select Comp   Compound Interest
Select Adv   Payments in Advance (at start of period)
Enter I% 4.0000 To enter tap the Entry Field
Tap button PMT 34.73 Read the Result
Enter PV 0.00 Must be 0.00
Enter FV 10,000.00 To enter tap the Entry Field
Tap button ? Schedule View the Schedule
Tap button ? Graph View the Graph

To Top

Main Screen

Buttons

General Buttons (Red or Green)

CA Clears All. The dates are set to the Current Calendar Date, and all the Numerical Entry Boxes to 0.00.

? Brings up an options menu: Help, Schedule, Graph, Save, Load, Send, Cancel.

To Top

Time Buttons (Blue)

Start sets the Start Date. Tapping the Start Date Entry Field does the same.

End sets the End Date. Tapping the End Date Entry Field does the same.

Now sets the respective Date to the current calendar date.

Changing dates automatically computes the Time between the Start Date and the End Date. Changing Time values sets the End Date to the Time from the Start Date.

The Start Date cannot be set later than the End Date, nor can the End Date be set earlier than the Start Date. If the Start Date is set to a date later than the End Date, both the dates are set to that later date. If the End Date is set earlier than the Start Date, the End Date is set to the Start Date.

To Top

Money Buttons (Golden)

The Money Buttons also serve as labels for the data entry fields. Thus, the data filed for Payment is to the left of the PMT button.

Once a golden button is tapped, it performs the computation for its value, and its label becomes red. This shows which value has been computed. Thus, PMT indicates that the computation has been performed to compute the Payment value from the rest of the data.

Time computes the Time for the given Money values and updates the Dates accordingly.

Time values can be entered as Years, Months, or Days.

I% computes the Growth (Interest) Rate for the given Money values as percent of of the Capital Value at the End (or Beginning) of each Compounding Period (or of the Capital at Start for Simple Interest). In the entry field, the Growth (Interest) Rate is always shown yearly (per annum). The rate applied to the selected Compounding Period is shown in the header of the Schedule.

PMT computes the Payment in each Compounding Period required to reduce the Capital at Start (PV) to 0.0, or to yield the required Future Amount (FV) at the end of the Time Period (End Date) for the given Interest Rate (I%). To compute Payment given PV, FV must be 0.00. To compute Payment given FV, PV must be 0.00. In the entry field, the Payment is always shown per Compounding Period.

PV computes the Present Value of a series of periodic payments (if FV set 0.0), or of a Capital Amount (FV) received after a given Time Period (if PMT set 0.0).

FV computes the Capital Value (Future Value) received after a given Time Period of a series of periodic payments (if PV set 0.0), or of a Capital Amount at Start (PV) (if PMT set 0.0).

To Top

Switches (Gray)

The switches select the Compounding Period, the Type of Compounding (compound, or simple), and the Payments timings. Tapping a switch button selects the required setting and recomputes the current computation with the new settings.

Compounding Period Switch

Year if selected, interest is added (and Payments made, if PMT is used) annually (once a year).

Semi if selected, interest is added (and Payments made, if PMT is used) semi-annually (twice a year).

Quarter if selected, interest is added (and Payments made, if PMT is used) quarterly (4 times a year).

Month if selected, interest is added (and Payments made, if PMT is used) monthly (12 times a year).

Week if selected, interest is added (and Payments made, if PMT is used) weekly (52 times a year).

Day if selected, interest is added (and Payments made, if PMT is used) daily (365 times a year).

Cont if selected, interest is added continuously. Is used only in PV/FV (capital growth, deposit accounts, etc.) computations. Cannot be used for PMT computations (loans, mortgages, annuities, sinking funds, etc.).

To Top

Interest Type Switch

Comp if selected, interest is added as a percent of the total capital at the time of compounding.

Simp if selected, interest is added as a percent of the initial Capital (PV).

To Top

Payment Timing Switch.

Adv if selected, payments are made in Advance (at start of each payment period). Takes effect only if PMT is used.

Arr if selected, payments are made in Arrears (at end of each payment period). Takes effect only if PMT is used.

To Top

Dates Entry Screen

Dates are entered or edited using the standard iPhone Date Picker. Month, Day or Year are selected by rotating the corresponding wheels with a downward or upward swipes until the required value is brought under the middle selection indicator strip. The label at the top of the screen (above the green and red buttons) shows the value being edited. The Accept Button ends the selection and returns to the Main Screen setting the edited value to the one selected. The Cancel Button ends the selection and returns to the Main Screen abandoning the selected value and leaving the original value unchanged.

To Top

Data Entry Keyboard/Calculator Screen

Overview

The data entry screen is optimized for money inputs. It has two display fields: one for the whole amounts (the major currency units) and another for the fractional amounts ("small change"). The entries in the active display field are red, an in the inactive one black. Tapping on one of the display fields makes it active.

At the top of the screen is the name of the value being edited.

Tapping a golden button enters the number marked on the button into the active display field, while the blue buttons perform calculator operations. The brown buttons are used for controlling the calculator persistent memory.

The Accept Button ends the selection and returns to the Main Screen setting the edited value to the one selected. The Cancel Button ends the selection and returns to the Main Screen abandoning the selected value and leaving the original value unchanged.

The C Button deletes the last digit in the active display field or clears the pending operation (if in progress), while the CA Button clears both the display fields, both the registers, and any pending operation.

Under the Accept Button there are two auxiliary display fields: the upper larger one shows the progress of the current calculator operation, the lower smaller one shows the memory state.

The keyboard calculator can operate on both positive and negative numbers. But negative results are converted to their absolute value (positive) when transferred to the main TimeMoney screen.

To Top

Calculator

The calculator provides 9 mathematical functions: 5 binary and 4 unary, as well as the = key which completes a binary operation.

To Top

Binary Operations

The binary operations are:

+ addition (X + Y),

- subtraction (X - Y),

* multiplication (X * Y),

/ division (X / Y),

pwr raising to power (Xy or pwr(X,Y)).

Binary operations involve two registers X and Y. When no binary operation is in progress numbers are entered into the X register. Pressing a binary operator causes the subsequent number to be entered into the Y register. This is shown on the upper auxiliary display as x + ?, which indicates that a second number is expected and will be entered into the Y register. Once the second number is entered the auxiliary display changes to x + y, which indicated that the currently displayed number is in the Y register. Pressing the = key completed the operation and displays the result.

Binary operations can be chained. Pressing a binary operator when the auxiliary display shows x + y completes the previous binary operation and transfers the result into the X register, while expecting the second number to be entered into the Y register, and the auxiliary display is set to x + ?.

Thus, 3 + 4 * 2 = 14,

while 4 * 2 + 3 = 11.

To Top

Unary Operations

The unary operations are:

1/x inverse,

exp ex (exponential function),

ln natural logarithm (ln X),

+/- sign change.

Unary operations operate on the current register and place the result in the same register and their effect is immediate.

Thus, 2 1/x 0.5,

3 + 2 1/x = 3.5,

while 3 + 2 = 1/x 0.2.

Pressing a unary operator key following a binary key, before the second number is entered (during a "pending binary operation", when the upper auxiliary display shows x + ?) has no effect. A pending binary operation can be cleared by tapping the C button.

To Top

Persistent Memory

To Top

The persistent memory stores one numeric value, and can be used for (a) storing intermediate results of calculations, (b) exchanging values between the main screen data fields, (c) exchanging values between different computations, and (d) for storing a value of interest for future reference.

The memory keys are:

MC clears the memory contents,

M+ adds the value in the current register to the memory contents,

M- subtracts the value in the current register from the memory contents,

MR (Memory Recall) - set the current register to the memory contents.

When the memory contains a non-zero value the small lower auxiliary display shows M. It is blank when the memory contains 0.00.

To Top

Options Menu (the ? Button)

Help

Displays this document.

Schedule

Displays a schedule of the current computation, showing changes in values for each compounding period. Thus, if the compounding is monthly and the period of a loan of fund ir 5 years, there will be 5 x 12 = 60 rows in the schedule, one for each month.

If a schedule page contains more than 30 period data rows, the schedule is paginated into pages containing at most 20 period data rows per each page.

The number of rows displayed in a single page and the number of rows per page in multi-page schedules can be set in the "Settings" application.

The Max Single Page Size value sets the limit for the schedule to be displayed as a single page. The Max Multiple Page Size value sets the size of each page for a multi-page schedule.

These page sizes limits can be configured using the standard iPhone Settings application.

The maximum page size of a single-page schedule can be set to 8, 20, or 30 period data rows. The maximum size of a page for multi-page schedule can be set to 8 or 20 period data rows.

To Top

Graph

Displays a graph for the current computation.

Save

Allows to save the current computation with the same, or a different name.

Load

Displays all the computations saved so far. Tapping on a computation name loads this computation and makes it current.

Swiping from left to right with a finger along a table row bring up a red "Delete" button. Swiping from right to left when the "Delete" button is displayed, hides this button. Tapping the "Delete" button deletes the computation.

To Top

Send

The Send option allows to send the schedule and graph of the current computation by email.

Schedules can be emailed as HTML ot CSV (Comma Separated Variables) text, and can be either included in the body of the email, or attached as separate files.

Graphs can be included as attachments, and scaled from x 1.0 to x 5.0 times the original size (300 x 378 pixels).

Graph image orientation (portrait or landscaple) can be selected.

To Top

Cancel

Tapping Cancel cancels the menu.

To Top

Specification

Range

The range of the numbers used for TimeMoney computations is 0.00 to +999,999,999,999,999.99. for money values and, theoretically, 0.00 to +999,999,999,999,999.9999 for interest rates. The theoretical range of the dates is 0001-01-01 to 9999-12-31, being the limits of the Date Picker.

In practice, however, the input values are limited by the result of the computation. And, if the result of the computation would result in an overflow, a warning message is displayed and the input is not accepted. And in view of the effect on the Time and Interest rates on the results, in practice the limits on these values are much lower than the theoretical limits.

The range of the numbers used in the calculator is
-999,999,999,999,999.9999 to +999,999,999,999,999.9999. This limit applies to the result.

Precision

The precision of the money computations is 2 decimal digits.

The precision of the interest rates is 4 decimal digits.

The precision of the calculator is 4 decimal digits.

For PMT computations, the minimal Current Compounding Period is 1.00.

To Top

Back to TimeMoney Help Screen