Date Calculator Instruction Manual

Date Calculator is a program that performs a variety of calendar related functions, including a perpetual calendar, calculating the number of days between two dates, or the date a certain number of days before or after a certain date. It also tells you the day of the week for a given date. It can also inform you of any appointments you today (provided you record these appointments in Date Calculator) and allow you to look at all appointments you have stored. This is useful for making a note of appointments once you have figured out what day they fall on using Date Calculator.

Date Calculator is very flexible. You can set it to count only certain days of the week, such as Monday through Friday, and whether to count the first and last day of the date range provided. It will automatically calculate costs if you are paying a certain amount per day. It also has features to automatically input certain common dates, like today's date. These features are described below.

Disclaimer

Date Calculator is provided "AS IS" without warranty of any kind. It is the sole responsibility of the end user to determine the applicability, accuracy, and appropriateness of this program for your particular purposes. It is recommended that the new user do a few simple calculations by hand and match them with the results obtained using Date Calculator. This will allow the user to verify that the calculation being performed by Date Calculator is the operation the user expects Date Calculator to perform. This is to allow the user to confirm that they correctly understand exactly what operations are being performed in each calculation done by Date Calculator. Neither Leithauser Research nor David Leithauser is responsible for any damages resulting from the use or misuse of this program.

Shareware Notice

Date Calculator is distributed as shareware. This means that you can try it for one month to see if it fits your needs. If it does, you are required to pay for it by sending the registration fee of $25.00 (US) to

David Leithauser
Leithauser Research
3624 Royal Fern Circle
DeLand, FL 32724

If you do not pay the registration fee within 60 days of the time you start using it, Date Calculator will stop functioning until you pay the registration fee. For further instructions, click on the Register button on the opening title page. This will show the Register page with further instructions, and a Print button that will print a form you can mail in to register Date Calculator. When you pay for Date Calculator, you will receive the unlock code, which you can then input in the Register window.

Installing Date Calculator in Windows

To install Date Calculator on your disk, run the datecarc.exe by double clicking on the datecarc.exe icon in Windows Explorer or My Computer, or by using the Run option under the Start menu to run datecarc.exe.

Using Date Calculator

When you run Date Calculator, you will see a screen full of controls and input boxes. Although these may seem confusing at first, they are really quite simple if you take a minute to familiarize yourself with them. For your particular needs, you may only use a small fraction of the functions provided by Date Calculator.

At the top of the Window, directly below the blue title bar, there is a series of menus. These menus include Mode, Appointments, Define Sequence, Holidays, Calendar, and Help. These menus are explained below.

Mode menu

There are two modes of operation for Date Calculator. The mode is selected by clicking on the Mode menu at the top of the main Date Calculator screen and then clicking on the mode you want. The current mode is marked with a check mark.

The first mode is Exact Days mode. Date Calculator always comes up in this mode when you first run it. In this mode, all time periods are measured in actual days. For example, if you calculate days between two dates, Date Calculator will give you the exact number of days between those two dates.

The second mode is Calendar Months. In this mode, all time periods are measured in terms of years, months, and days. For example, the time between January 5 and February 5 is one month and the time between February 5 and March 5 is one month, even though January 5 to February 5 is 31 days and February 5 and March 5 is 28 days. Some of the functions that are available for the Exact Days mode, such as skipping holidays when counting, are not available for the Calendar Months mode because they are not relevant. The following instructions will first discuss the Exact Days mode, and then later explain the Calendar Months mode.

Exact Days mode

There are three operations you can perform in the Exact Days mode. These operations are calculating the number of days between two dates, calculating the date a given number of days after a given date, and calculating the date a given number of days before a given date. There is a box labeled "Calculate" in the upper left corner of the window with option buttons to select which of these operations you want to perform. You can click on the operation you want to choose with a mouse to select it. These operations are explained below.

1) Calculating days between dates in exact days mode

When you are performing this operation, you will see input boxes for Start Date, End Date, and Cost/Day. You would input the date you want to start counting from in the Start Date box and the last date to count in the End Date box. You can input dates in a variety of formats, such as Jan. 1, 2004 or 1-1-04 or 1/1/2004. There is an advantage for non-US users to use three letter month abbreviations, because it insures that the program is using the correct date. Using non-US formats, such as Day-Month-Year, could cause confusion on some computers. Incidentally, Date Calculator has a few time saving features for inputting data such as dates. These will be explained later.

If you are calculating expenses, you can input a value in the Cost/Day box. If you do this, Date Calculator will not only calculate the number of days, but also the total cost.

You may notice when you input a date in the Start Date or End Date box that a day of the week appears next to that date. Date Calculator automatically calculates the day of the week for the date in the input box (and also for dates generated by calculations). As you are typing in the date manually, you may notice this day of the week changing. This is because Date Calculator is calculating the day for date as it currently appears. If you are typing 12-12-04, for example, a day will appear when you have gotten to 12-1 as Date Calculator calculates the day for December 1, but will change when you type in the following 2. Just ignore the day of the week displayed until you have input the entire date.

In the top middle of the Date Calculator form there are check boxes to allow you to include the first or last day of the date range. For example, if you have a start date of Jan. 1, 2000 and an end date of 1/1/2001, Date Calculator will count Jan. 1, 2000 if the Start Date box is checked and will count 1/1/2001 if the End Date is checked. You can check both boxes if you want to count both dates. The default is to count only the start date.

In the upper right corner is a powerful option to allow you to select which days of the week to skip. You can put a check in the day for each day you want to skip. (The default is no days.) For example, if you wanted to count all the days between today and January 1, 2001, you would have no days of the week checked. If, however, you only want to count workdays between those two dates, you would click on the Saturday and Sunday boxes to checks those boxes. Date Calculator would then count the weekdays between those two dates. If you wanted to count the number of weeks between two dates, you could simply check all but one day of the week.

There is also a check box for holidays. If you have check this box, the holidays that you have stored in Date Calculator will not be counted, just as weekend days would not be counted if you had checked Saturday and Sunday. How to input a list of holidays to skip is explained later in this manual.

There are shortcut buttons at the bottom of the frame containing the check boxes to help you quickly select common configurations, such as weekend days. Note that although Date Calculator has an All button there, this is only to help you quickly mark the check boxes if you only what to uncheck one or two days. Date Calculator will not do any calculation if all day boxes are checked.

When you have set all the fields the way you want them, click on the Calculate button (or press the ENTER button on your keyboard) to perform the calculation. After performing one calculation, you can simply change the data in the input boxes and click on the Calculate button to do the calculation again.

2) Calculating End Date and Start Date in exact days mode

The calculation of the End Date allows you to input a Start Date and a number of days, and Date Calculator will calculate the date at the end of that number of days. The calculation of the Start Date is the same process, except that it counts backward. For these operations, you need to input the Start Date (or End Date) and the number of days to count forward (or backward).

With these operations, the check boxes for counting the Start Date and the End Date disappear. Date Calculator automatically does not count the start date but does count the end date in this calculation.

The selection of which days of the week to skip affects the operations to find the End and Start Date. Suppose you want to find the date when 100 working days have passed after today. You can input today's date into the Start Date, 100 into the Days box, and check the Saturday and Sunday boxes in the "Count" frame. This will give you a different result (a later date) than if you had all the days of the week counted. Likewise, you would get an earlier date if you calculated the Start date (the date a number of days before the End Date) using only weekdays instead of all days. You can, of course, also check the Holidays box so that holidays will not be counted.

Some people like to find a whole series of End (or Start) Dates based on a common sequence of numbers of days. For example, some people want to know the dates 2, 3, 5, 8, 13, 21, and 34 days after a certain Start Date. If you put a series of number of days separated by commas into the Days text box, Date Calculator will sequentially calculate the date for each number of days after the start date. Each time you hit the Calculate button, Date Calculator will calculate the next date in the sequence. For example, if you input Jan. 1, 2004 as the start date and "3,5,8" (without the quotation marks) in the Days box, clicking the Calculate button once would give you Jan. 4, 2004. Clicking it again would give you Jan. 6, 2004. Clicking it again would give you Jan. 9, 2004. Once you have reached the last day in the sequence, clicking on the Calculate button will not perform an additional calculation.

To simplify this process, Date Calculator allows you to store up to three sequences of numbers, such as 2,3,5,8,13,21. Once you have stored one or more sequences of numbers, a button for each sequence will appear below the Days input box. These buttons will be labeled "Sequence 1", "Sequence 2", etc. Clicking on a sequence button will automatically put the entire sequence into the Days input box. The process of inputting (setting up) sequences is explained later in this document.

If the Print box (explained below) is checked, you do not have to press the Calculate button repeatedly. Date Calculator will calculate and print all the dates immediately.

Calendar Months mode

This mode expresses time in years, months, and days instead of simply as days. Because years and months are not always the same length, this can produce some results that may seem odd at first. For example, the time between January 5, 2001 and February 5, 2001 is one month. The time between February 5, 2001 and March 5, 2001 is also one month, even though January 5, 2001 to February 5, 2001 is 31 days and February 5, 2001 to March 5, 2001 is 28 days. If the day of the month of the start month is more than the number of days in the end month, the end date is still one month from the start date. For example, from January 28, 2001 to February 28, 2001 is one month, but so is January 31, 2001 to February 28, 2001. A date one month and 2 days from January 31 is always March 2, because the one month carries the date to the end of February, and the additional two days makes it March 2. This is true regardless of whether it is a leap year or not.

In Calendar Months mode, as in Exact Days mode, the control in the upper left corner of the screen selects which function of Date Calculator you will be using. These functions are calculating the amount of time in years, months and days between two dates, calculating the date a given number of years, months, and days from a given date, and calculating the date of a given number of days before a given date. You can click on the operation you want to choose with a mouse to select it. The default (the one Date Calculator has selected when you first switch to Calendar Months mode) is to calculate the time between two dates. These operations are explained below.

1) Calculating time between dates in Calendar Months mode

When you are performing this operation, you will see input boxes for Start Date and End Date. You would input the date you want to start counting from in the Start Date box and the last date to count in the End Date box. You can input dates in a variety of formats, such as Jan. 1, 2004 or 1-1-04 or 1/1/2004. There is an advantage for non-US users to use three letter month abbreviations, because it insures that the program is using the correct date. Using non-US formats, such as Day-Month-Year, could cause confusion on some computers.

You may notice when you input a date in the Start Date or End Date box that a day of the week appears next to that date. Date Calculator automatically calculates the day of the week for the date in the input box (and also for dates generated by calculations). As you are typing in the date manually, you may notice this day of the week changing. This is because Date Calculator is calculating the day for date as it currently appears. If you are typing 12-12-04, for example, a day will appear when you have gotten to 12-1 as Date Calculator calculates the day for December 1, but will change when you type in the following 2. Just ignore the day of the week displayed until you have input the entire date.

When you have input the start and end dates, click on the Calculate button (or press the ENTER button on your keyboard) to perform the calculation. After performing one calculation, you can simply change the data in the input boxes and click on the Calculate button to do the calculation again.

2) Calculating End Date and Start Date in Calendar Months mode

The calculation of the End Date allows you to input a Start Date and a number of years, months, and days, and Date Calculator will calculate the date at the end of that amount of time. The calculation of the Start Date is the same process, except that it counts backward. For these operations, you need to input the Start Date (or End Date) and the number of years, months, and days to count forward (or backward).

Managing Appointments

Date Calculator allows you to store a date book of appointments you have. This is useful if you calculate the date a given number of days in the future when you have to do something (like have a court appearance or exercise an option) and you want to remind yourself when the date comes. You can add appointments to your appointment database, delete appointments, and view your list of appointments. When you run Date Calculator, it will automatically show you any appointments you have today. The Appointments menu at the top of Date Calculator allows you to manage these appointments. The options under this menu are described below.

1) View appointments

Under the Appointments menu, you have the option to view appointments. If you select this option, a window appears that shows you a list of all your appointments in date order. However, there is a drop-down list box at the top of the window that allows you to select any one specific day you want to see your appointments for. Any date that you have recorded an appointment for will appear on this list. This allows you to easily find any appointments on any specific day. To make it particularly easy to find today's appointments, there is a button beside the drop down box that will automatically select today's date if you click on it. Note: Remember that a list of today's appointments automatically comes up when you first run Date Calculator if you have any appointments today.

2) Add Appointments

This option under the Appointments menu allows you to add an appointment to your date book. When you select this option, a window appears with two text boxes. The first is labeled "Date". You can input any date in any format you find convenient, such as 11/1/2005 or Nov. 1, 2005 or 11-1-05. Non-US users may wish to spell out months, to avoid possible confusion about the month-date order. If you have just performed a date calculation, such as finding an end date, the result of that calculation will automatically appear in the Date input box for your convenience, but you can change it if you wish.

The second text box asks for the description of the appointment. Input any short phrase (no longer than the length of the text box) to describe your appointment. Typical descriptions might be "Due in court 9 AM" or "Exercise IBM option."

When you have input the date and description, click on the Add button or press ENTER on your keyboard. The appointment you have input will be stored, and the text boxes will clear to allow you to input another appointment. When you have input all appointments, click on the Close button or press Esc on your keyboard.

3) Delete Appointments

You can delete appointments you have input using this option under the Appointments menu. When you select this option, you will see a list of all your appointments. As with the "View Appointments" option, you can narrow down this list by selecting a date from the drop down menu. Select the appointment you want to delete by clicking on it in the list box. Once you have selected an appointment, the Delete button will become enabled. Click on this button to delete the selected appointment. You can repeat this process to delete as many appointments as you wish. When you are finished deleting appointments, click on the Close button.

Note: Appointments that have expired (when you are passed the appointment date) are automatically deleted from your appointment list. There is no need to go through the list looking for outdated appointments. The main reason to delete an appointment from the list is if the appointment is cancelled. If there is a mistake in an appointment you have entered (either the date or the description), you can also delete the appointment and then reenter it correctly. This is the only way you can edit an appointment you have input.

Defining Sequences

Some people like to calculate the end date after a specific date for a whole sequence of number of days, as explained above. To save you the trouble of inputting a long series of numbers every time you want to perform an End Date or Start Date calculation on a sequence of numbers, you can store up to three sequences of numbers. To do this, you would use the "Define Sequence" menu.

To do this, click on the Define Sequence on the top of the form. To input the first sequence, click on the Sequence 1 item. An input box will appear. You can input the sequence of numbers, separated by commas, into the input box. For example, you could input "3,5,8,13,21" (without the quotation marks). Then click on the Ok button. This will store the sequence you have input on your hard disk.

If you have already input a sequence, the existing sequence will appear in the input box for sequence 1 when it first appears. This allows for easy changes. You also can delete all the numbers in the input box and Click on Ok to delete a sequence.

If you have already saved a sequence 1, you also will have the option of inputting a sequence 2. Click on the Define Sequence menu on the top of the window. To input the second sequence, click on the Sequence 2 item.

If you have already saved a sequence 2, you can then input a sequence 3. When you click on the Define Sequence menu on the top of the form, select "Sequence 3" and input your sequence.

Once you have stored a Sequence 1, 2, or 3, any time you are calculating an End Date or Start Date, a button for that sequence will appear under the Days input box. Clicking on this button will put the entire sequence into the Days box. Then you can just click on the Calculate button and see the entire sequence of End Days, as explained above.

The Holidays menu

As explained above, you may want to input a list (or several lists) of holidays to skip when calculating dates. The Holidays menu allows you to manage these holiday lists. The options under this menu are explained below.

1) Create new holiday file

You can create up to nine separate holiday files. To create a new holiday file, click on "Create new holiday file" under the Holidays menu. Date Calculator will ask you for a name for the file. Input a name and click on the Ok button. The box will then disappear. The new file name will be added to the file list under the Holiday menu. This new file will automatically be the current holiday file.

2) Selecting a holiday file

If you have created more than one holiday file, you can select which one Date Calculator is currently using by selecting that file under the Holidays menu. Just click on the Holiday menu and then click on the name of the file you want Date Calculator to use as a holiday list. The current holiday list is indicated by a check mark.

3) Add holiday

If you want to add a holiday to the current holiday list for Date Calculator to skip, click on the Holidays option at the top of the main Date Calculator window and select Add Holidays from the list. You will then see a window that will allow you to select the month and day of the month that the holiday falls on. You can also select the year. You can select the "Every Year" radio button if the holiday falls on the same date each year, like Christmas. If the holiday falls on different dates each year, like Thanksgiving does, you will need to select a specific year, and you will need to input the date for each year where you want the holiday skipped. For example, if you wanted Thanksgiving skipped during date calculation for both 2004 and 2005, you would need to input this date as two separate dates. You can input the date of the month and the year either by typing in the number, or by selecting this number from the drop down list box.

When you have selected the month, day, and year for the holiday, click on the Add button. The date you have selected will be added to Date Calculator's holiday list. The holidays in this list are shown (in alphabetical order) on the Add Holidays window. The screen will then be cleared of values to allow you to input another holiday. When you have finished inputting holidays, click on the Done button.

4) Delete holiday

To remove a holiday, click on the Holidays menu at the top of the main Date Calculator window and select the Delete Holiday option. You will see a window listing all the holidays you have input (in alphabetical order). Select the holiday you want to delete and then click on the Delete button. When you are finished deleting holidays, click on the Done button. You can also use the Delete Holiday option to just view the list of holidays you have stored. Just select this option, but do not delete any holidays. Just click on the Done button when you have finished viewing the holidays.

Having a lot of holidays listed in Date Calculator can significantly slow down the date calculations. This is because Date Calculator must check each holiday repeatedly to see if it matches the current date it is counting. It is a good idea to remove any holidays that apply only in a year that has passed, to speed up Date Calculator's computations.

Perpetual Calendar function

You can see a calendar of any month of any year by clicking on the Calendar option on the top menu. A form will appear that allows you to select the month and year you want a calendar for. You can select the month from the pick list on the left. You can select a year from 1900 to 2100 from the pick list on the right, or type a year in the text box on top of the pick list. Then click on the Ok button. The calendar for that month and year will appear. Click on the Ok button to return to the main Date Calculator window.

Time saving features

Date Calculator has a number of features that save you time when inputting commonly used data. You can input Today's date or the third Friday of any month of the year into either the Start Date or End Date box with a click of the mouse. As explained above, you can input whole sequences of number of days to count with a single sequence button.

To input today's date into a date box, first click on the date box (Start Date or End Date) where you want today's date to go. Then click on the Today button.

To input the date of the third Friday of any month, click on the input box where you want to input the date (Start Date or End Date). Then click on that month in the list box. (You may have to scroll through the list box for months late in the year.) If you select a month that has already passed in the current year, the date you get will be for that month next year. This feature is particularly useful to option traders, because it saves the time of looking up the date of the third Friday of a given month. Normally, you would use this feature to input today's date into the Start Date box and the third Friday of a month into the End Date box.

Printing your results

Below the frame containing the check boxes for the days to count is a single check box marked Print. If this box is checked, a full description of the calculation and its results will be sent to the printer. If this printer function is turned on, Date Calculator will not pause when doing repetitive calculations, such as all the End Dates in a series, as explained above.

When you do a calculation with the Print box checked, Date Calculator will print the results and eject the paper from your printer immediately. Since it uses a full sheet of paper for each calculation, you might want to use the Print option only on a calculation for which you really want to save the results.

Uninstalling Date Calculator

If, after trying Date Calculator, you decide that you do not want to keep it, exit Date Calculator by clicking on Files/Exit if it is currently running. Then open the Windows Control Panel and select Add/Remove Programs or Programs and Features (depending on which Windows operating system you have). Select Date Calculator and follow the standard uninstall procedure for your computer. This will totally remove Date Calculator from your computer.

Bug reports and suggestions

Reports of problems or suggestions for improvement are welcome. Send such reports or suggestions to:

David Leithauser
Leithauser Research
3624 Royal Fern Circle
DeLand, FL 32724

You also can send Internet email to Leithauser@aol.com. In cases of emergency, you can call Leithauser Research at (386) 738-0418 between the hours of 10 AM and 10 PM ET.

If I feel that the improvement would be of interest to most users, I will make it for free and send you the improved version. If the improvement is unusual and suited only to your specific needs, I can give you a price quote for a customized version of Date Calculator (see below).

Custom programming

Leithauser Research does custom programming. If you would like a custom program of any type written, please contact me at the above address for Leithauser Research, or send email to Leithauser@aol.com. Describe the program you would like written in as much detail as possible and I will give you a price estimate. Programs can be DOS or Windows.

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