gcalctool Manual
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Feedback
To report a bug or make a suggestion regarding the gcalctool application or this manual, follow the directions in the GNOME Feedback Page.
| Abstract |
gcalctool is a calculator for GNOME. It includes basic, advanced, financial, and scientific modes and uses a multiple precision package to do its arithmetic to give a high degree of accuracy. |
Introduction
The gcalctool application provides the following modes for different types of mathematical functionality:
- Basic
The default mode. Provides standard calculator functions. You can perform standard addition, subtraction, division, and multiplication functions in Basic mode and you can use all of the Basic functions in each of the other modes.
- Advanced
Provides advanced calculator functions. You can store numbers in 10 different memory registers, and easily retrieve and replace the numbers in the memory registers. You can use all of the Advanced functions in Financial, Scientific and Programming modes.
- Financial
Provides several complex financial functions.
- Scientific
Provides many additional mathematical functions, including trigonometric functions. You can also store your own functions and constants, when you use Scientific mode.
- Programming
Provides functions useful to a programmer, including bitwise functions and a bit editor.
You can use gcalctool in the following numbering systems:
Getting Started
You can start gcalctool in the following ways:
- Menu
Choose Accessories->Calculator.
- Command line
Execute the following command: gnome-calculator
When you start gcalctool, the following window is displayed:
The gcalctool window contains the following elements:
- Menubar
The menus on the menubar contain all of the commands that you need to work with gcalctool.
- Display area
The display area shows the numbers that you enter, and the results of calculations.
- Mode area
The mode area displays the buttons for the current mode. The Basic mode buttons are always displayed. Advanced mode buttons are also available in Financial, Scientific and Programming modes.
- Popup Menu
The
symbol on a gcalctool button indicates that a popup menu is displayed when you click on that button.- Status Bar
The status bar displays messages on the status of your calculations.
Usage
To Use Calculator Functions
To perform a calculation, use one of the following methods:
Click on the gcalctool buttons to enter numbers and functions.
Give focus to the gcalctool window, then use the keyboard or numeric keypad to specify the calculation that you want to perform. For a complete list of keyboard shortcuts, see the Section called Quick Reference: Keyboard Shortcuts.
The gcalctool application automatically displays numbers with more than 40 digits, and small numbers, as exponential numbers. For example, the following table shows the value that is displayed when you use the decimal numeric base with an accuracy of 2 significant places:
For information about how to enter a number in exponential format, see the Section called To Enter Exponential Numbers.
To Display a Separator in Large Numbers
To insert a separator between every three digits to the left of the numeric point in decimal base, choose View->Show Thousands Separator.
 | Different countries and cultures have varying conventions for how to communicate. These conventions include the language spoken and the character used as a numeric separator. gcalctool has been internationalized so users can adapt to their own conventions. This is done by setting a specific locale. We can't determine what locales will exist, except for a standard one called the C locale. When you use the C locale, the separator character is not displayed. |
To Copy and Paste in the Display Area
To copy the result of a calculation, choose Edit->Copy. You can paste the value into another application.
To paste a previously copied value into the display area, choose Edit->Paste.
To Perform Basic Calculations
Basic mode is displayed by default when you first start gcalctool. To explicitly invoke Basic mode, choose View->Basic.
The calculator memory registers are unavailable in Basic Mode. In other words, View->Memory Registers is inactive.
To Perform Simple Calculations
To perform simple calculations, use the buttons described in Table 1.
Table 1. Performing Simple Calculations
|
Function |
Button |
Description |
Example |
Result |
|---|---|---|---|---|
Numerals | 0 to 9 inclusive | In decimal and hexadecimal base, all numerals are available. In octal base, 8 and 9 are unavailable. In binary base, only 0 and 1 are available. The default base is decimal. | 1 | 1 |
Numeric point | . | Starts the fractional part of a numeric entry. | 1 . 2 | 1.2 |
Calculate a result | = | Displays the result of the current calculation in the current base. | 1 + 2 = | 3 |
Addition | + | Adds the current value in the display area to the next number that you enter. | 1 + 2 = | 3 |
Subtraction | - | Subtracts from the current value in the display area the next number that you enter. | 3 - 2 = | 1 |
Multiplication | * | Multiplies the current value in the display area by the next number that you enter. | 3 * 2 = | 6 |
Division | / | Divides the current value in the display area by the next number that you enter. | 6 / 3 = | 2 |
Change the arithmetic sign | +/- | Changes a positive number to a negative number, or a negative number to a positive number. | 8 +/- | -8 |
To Erase Characters
To erase characters, use the buttons described in Table 2.
Table 2. Erasing Characters
|
Function |
Button |
Description |
Example |
Result |
|---|---|---|---|---|
Backspace | Bksp | Removes the rightmost character from the display area. | 1 + 22 Bksp = | 3 |
Clear Entry | CE | Removes the current value from the display area. This operation is the same as Clr | 1 + 22 CE = | 0 |
Clear | Clr | Resets the current value in the display area to zero and removes any previous calculation results. Clr also deselects the Hyp and Inv options in Scientific. | 1 + 22 Clr | 0 |
To Display ASCII Values
To display the ASCII value of a character, choose Edit->Insert ASCII Value.
The Insert ASCII Value dialog is displayed.
Enter the required character in the Character field, then click Insert. The ASCII value of that character, in the current numeric base, appears in the display area. For example, the ASCII value of B in decimal base is 66.
To Perform Advanced Calculations
To change to Advanced mode, choose View->Advanced.
When you change to Advanced mode, the following buttons are displayed to the right of the Basic mode buttons:
Table 3. Performing Advanced Calculations
|
Function |
Button |
Description |
Example |
Result |
|---|---|---|---|---|
Percentage | % | Divides the current value by 100. | 560 % = | 5.60 |
Reciprocal | 1/x | Divides 1 by the current value in the display area. | 4 1/x | 0.25 |
Square Root | Sqrt | Calculates the square root of the current value in the display area. | Sqrt 9 )= | 3 |
Square | x2 | Calculates the square of the current value in the display area. | 3 x2 | 9 |
Integer Portion | Int | Calculates the integer portion of the current value in the display area. | -23.45 Int | -23 |
Fractional Portion | Frac | Calculates the fractional portion of the current value in the display area. | -23.45 Frac | -0.45 |
Absolute Value | Abs | Calculates the absolute value of the current value in the display area. | -23.45 Abs | 23.45 |
Parentheses | ( and ) | Calculations within parentheses are performed first. You can nest parentheses to any level. |
2 + 3 * 4 = 2 + ( 3 * 4 ) | 20 14 |
To Use the Calculator Memory Registers
You can store values in any of the ten gcalctool memory registers R0 to R9. To display the memory registers, choose View->Memory Registers.
The memory registers can be dismissed by either choosing View->Memory Registers again, or by clicking on the Close button in the memory register window.
Table 4 describes the memory functions that you can use.
Table 4. Memory Functions
|
Function |
Button |
Description |
Example |
Result |
|---|---|---|---|---|
Store Value in Memory Register | Sto | Stores the current contents of the display area in the specified memory register. Click Sto, then select a memory register from the popup menu. To clear a memory register during a gcalctool session:
| 22 Sto R2 | The value 22 is stored in memory register R2. |
Retrieve Value From Memory Register | Rcl | Retrieves the contents of the specified memory register. Click Rcl, then select the memory register from the popup menu. | 0 Rcl R2 | The value in the display area is 22. |
Exchange Memory Register Value and Displayed Value | Exch | Exchanges the contents of the specified memory register and the current value in the display area. Click Exch, then select the memory register from the popup menu. | 44 Exch R2 | The value in the display area changes from 44 to 22, the value in R2 changes from 22 to 44. |
If you use keyboard shortcuts, you can use the keyboard to specify the memory register, as shown in the following examples:
To Perform Financial Calculations
To change to Financial mode, choose View->Financial.
When you change to Financial mode, the following buttons are displayed above the Basic and Advanced mode buttons:
To perform financial calculations, use the buttons described in Table 5.
Table 5. Performing Financial Calculations
|
Function |
Button |
Description |
Example |
Result |
|---|---|---|---|---|
Compounding Term | Ctrm | Calculates the number of compounding periods necessary to increase an investment from a present value to a future value, at a fixed interest rate per compounding period. | You have just deposited $8000 in an account that pays an annual interest rate of 9%, compounded monthly. Given the annual interest rate, you determine that the simple monthly interest rate is 0.09 / 12 = 0.0075. To calculate the time period necessary to double your investment, click Ctrm, and put the following values into the text entries:
Click Calculate | 92.77 The investment doubles in value in 92.77 months. |
Double-Declining Depreciation | Ddb | Calculates the depreciation allowance on an asset for a specified period of time, using the double-declining balance method. | You have just purchased an office machine for $8000. The useful life of this machine is six years. The salvage value after six years is $900. To calculate the depreciation expense for the fourth year, using the double-declining balance method, click Ddb and put the following values into the text entries:
Click Calculate | 790.12 The depreciation expense for the fourth year is $790.12. |
Future Value | Fv | Calculates the future value of an investment based on a series of equal payments at a specific periodic interest rate, over the number of payment periods in the term. | You plan to deposit $4000 in a bank account on the last day of each year for the next 20 years. The account pays 8% interest, compounded annually. Interest is paid on the last day of each year. To calculate the value of your account in 20 years, press Fv and put the following values into the text entries:
Click Calculate | 183047.86 At the end of 20 years, the value of the account is $183,047.86. |
Gross Profit Margin | Gpm | Calculates the resale price of a product, based on the product cost and the wanted gross profit margin. | You sell T-Shirts online. Each T-Shirt cost you $12 in material and labor. You want to sell the T-Shirts with a Gross Profit Margin of 0.40 - for every five dollars you earn, you want two to be profit. To calculate the price you would have to sell your T-Shirts for, press Gpm and put the following values into the text entries:
Click Calculate | 20 You will have to sell your T-Shirts for $20 |
Periodic Payment | Pmt | Calculates the amount of the periodic payment of a loan, where payments are made at the end of each payment period. | You are considering a $120,000 mortgage for 30 years at an annual interest rate of 11.0%. Given the annual interest rate, you determine that the simple monthly interest rate is 0.11 / 12 = 0.00917. The term is 30 * 12 = 360 months. To calculate the monthly repayment for this mortgage, press Pmt and put the following values into the text entries:
Click Calculate | 1143.15 The monthly repayment is $1143.15. |
Present Value | Pv | Calculates the present value of an investment based on a series of equal payments, discounted at a periodic interest rate, over the number of payment periods in the term. | You have just won a million dollars. The prize is awarded in 20 annual payments of $50,000 each. Annual payments are received at the end of each year. If you were to accept the annual payments of $50,000, you would invest the money at a rate of 9%, compounded annually. However, you are given the option of receiving a single lump-sum payment of $400,000 instead of the million dollars annuity. To calculate which option is worth more in today's dollars, press Pv and put the following values into the text entries:
Click Calculate | 456427.28 The $1,000,000 paid over 20 years is worth $456,427.28 in present dollars. |
Periodic Interest Rate | Rate | Calculates the periodic interest necessary to increase an investment of a present value to a future value, over a number of compounding periods. | You have invested $20,000 in a bond. The bond matures in five years, and has a maturity value of $30,000. Interest is compounded monthly. The term is 5 * 12 = 60 months. To calculate the periodic interest rate for this investment, press Rate and put the following values into the text entries:
Click Calculate | .00678 The monthly interest rate is 0.678%. The annual interest rate is 0.678% * 12 = 8.14%. |
Straight-Line Depreciation | Sln | Calculates the straight-line depreciation of an asset for one period. The depreciable cost is cost - salvage. The straight-line method of depreciation divides the depreciable cost evenly over the useful life of an asset. The useful life is the number of periods, typically years, over which an asset is depreciated. | You have just purchased an office machine for $8000. The useful life of this machine is six years. The salvage value after six years is $900. To calculate the yearly depreciation expense, using the straight-line method, prss Sln, and put the following values into the first three memory registers:
Click Calculate | 1183.33 The yearly depreciation expense is $1183.33. |
Sum-Of-The-Years'-Digits Depreciation | Syd | Calculates the depreciation allowance on an asset for a specified period of time, using the Sum-Of-The-Years'-Digits method. This method of depreciation accelerates the rate of depreciation, so that more depreciation expense occurs in earlier periods than in later ones. The depreciable cost is cost - salvage. The useful life is the number of periods, typically years, over which an asset is depreciated. | You have just purchased an office machine for $8000. The useful life of this machine is six years. The salvage value after six years is $900. To calculate the depreciation expense for the fourth year, using the sum-of-the-years'-digits method, press Syd, and put the following values into the text entries:
Click Calculate | 1014.29 The depreciation expense for the fourth year is $1014.29. |
Payment Period | Term | Calculates the number of payment periods that are necessary during the term of an ordinary annuity, to accumulate a future value, at a certain periodic interest rate. | You plan to deposit $1800 in a bank account on the last day of each year. The account pays 11% interest, compounded annually. Interest is paid on the last day of each year. To calculate the time period necessary to accumulate $120,000, press Term, and put the following values into the text entries:
Click Calculate | 20.32 $120,000 accumulates in the account in 20.32 years. |
To Perform Scientific Calculations
To change to Scientific mode, choose View->Scientific.
When you change to Scientific mode, the following buttons are displayed above the Basic and Advanced mode buttons:
To Set the Accuracy
To set the accuracy of the display area and of the memory registers, click Acc, then select from the popup menu the accuracy level that you require. The current accuracy level is indicated by a preceding black circle in the popup menu. Up to 99 significant places can be displayed. The default accuracy is 9 significant places.
To set the accuracy level above 9, select Other (9) ..., then choose the accuracy level you require in the Set Precision popup.
By default, trailing zeroes are not shown. To display trailing zeroes, click Acc then select Show Trailing Zeroes from the popup menu, or choose View->Show Trailing Zeroes. A preceding check mark in the Acc popup menu or View menu indicates that the Show Trailing Zeroes option has been selected. To hide trailing zeroes, choose View->Show Trailing Zeroes again.
The examples in the following table show how the accuracy setting affects x in the display area, when you use decimal base, with the Show Trailing Zeroes option selected, for the 1 / 8 = x calculation:
To Set the Display Type
To set the display type, select one of the buttons described in Table 6.
Table 6. Setting the Display Type
|
Function |
Button |
Description |
|---|---|---|
Engineering Display Type | Eng | Sets the display type to engineering format. Results are displayed in scientific notation. The exponent is always a multiple of three. |
Fixed-Point Display Type | Fix | Sets the display type to fixed-point format. Results are not displayed in scientific notation. Fixed-point is the default display type. If you change from scientific mode to either basic mode or financial mode, gcalctool automatically sets the display type to fixed-point format. |
Scientific Display Type | Sci | Sets the display type to scientific format. Results are displayed in scientific notation, with a fixed number of numeric digits. |
To Set the Trigonometric Type
To set the trigonometric type, select one of the buttons described in Table 7.
To Set the Trigonometric Options
To set the trigonometric options, use the options described in Table 8.
Table 8. Setting the Trigonometric Options
|
Function |
Button |
Description |
|---|---|---|
Hyperbolic Option Indicator | Hyp | Selects the hyperbolic option for use with the trigonometric functions. |
Inverse Option Indicator | Inv | Selects the inverse option for use with the trigonometric functions. |
By default, the options described in Table 8 are not selected. Click Clr to deselect these options.
To Calculate Trigonometric Values
To calculate trigonometric values, use the buttons described in Table 9.
Table 9. Calculating Trigonometric Values
|
Function |
Button |
Description |
Example |
Result |
|---|---|---|---|---|
Cosine cos | Cos, Hyp option not selected, Inv option not selected | Calculates the cosine of the current value in the display area. | 60 Cos | 0.5 |
Arc Cosine acos | Cos, Hyp option not selected, Inv option selected | Calculates the arc cosine of the current value in the display area. | 0.5 Inv Cos | 60 |
Hyperbolic Cosine cosh | Cos, Hyp option selected, Inv option not selected | Calculates the hyperbolic cosine of the current value in the display area. | 0.4 Hyp Cos | 1.081072372 |
Arc Hyperbolic Cosine acosh | Cos, Hyp option selected, Inv option selected | Calculates the arc hyperbolic cosine of the current value in the display area. | 1.6 Hyp Inv Cos | 1.046967915 |
Sine sin | Sin, Hyp option not selected, Inv option not selected | Calculates the sine of the current value in the display area. | 90 Sin | 1 |
Arc Sine asin | Sin, Hyp option not selected, Inv option selected | Calculates the arc sine of the current value in the display area. | 1 Inv Sin | 90 |
Hyperbolic Sine sinh | Sin, Hyp option selected, Inv option not selected | Calculates the hyperbolic sine of the current value in the display area. | 0.4 Hyp Sin | 0.410752326 |
Arc Hyperbolic Sine asinh | Sin, Hyp option selected, Inv option selected | Calculates the arc hyperbolic sine of the current value in the display area. | 1.6 Hyp Inv Sin | 1.248983328 |
Tangent tan | Tan, Hyp option not selected, Inv option not selected | Calculates the tangent of the current value in the display area. | 45 Tan | 1 |
Arc Tangent atan | Tan, Hyp option not selected, Inv option selected | Calculates the arc tangent of the current value in the display area. | 1 Inv Tan | 45 |
Hyperbolic Tangent tanh | Tan, Hyp option selected, Inv option not selected | Calculates the hyperbolic tangent of the current value in the display area. | 0.6 Hyp Tan | 0.537049567 |
Arc Hyperbolic Tangent atanh | Tan, Hyp option selected, Inv option selected | Calculates the arc hyperbolic tangent of the current value in the display area. | 0.6 Hyp Inv Tan | 0.693147181 |
To Calculate Logarithms
To calculate logarithms, use the buttons described in Table 10.
Table 10. Calculating Logarithms
|
Function |
Button |
Description |
Example |
Result |
|---|---|---|---|---|
Common Logarithm Base 10 | Log10 | Calculates the common logarithm (base 10) of the current value in the display area. | 10 Log10 | 1 |
Natural Logarithm | Ln | Calculates the natural logarithm of the current value in the display area. | 10 Ln | 2.30 |
Common Logarithm Base 2 | Log2 | Calculates the common logarithm (base 2) of the current value in the display area. | 10 Log2 | 3.32 |
| Common antilogarithm and natural antilogarithm are not supported in this version of gcalctool. |
To Enter Exponential Numbers
To enter exponential numbers, use the Exp button.
The Exp button enables you to enter numbers in scientific notation, that is, mantissa * baseexponent:
- mantissa
Current non-zero value in the display area. If the current value in the display area is zero, the mantissa is 1.0.
- base
2, 8, 10, or 16 for binary, octal, decimal, and hexadecimal numeric base respectively.
- exponent
Next number that you enter.
When you click Exp, the calculator displays . + to represent base to the power of the next number that you enter.
To change the sign of the number, use the +/- button before the Exp button. To change the sign of the exponent (the power to which the number is raised) use - after the Exp button.
To enter a decimal number in exponential format, use the guidelines in the following table:
To Use Constant Values
Click Con to display the list of defined constant values. All constant values are specified in decimal numeric base, even if the current numeric base is not decimal.
Select a constant from the menu to enter its value in the display area. If you use the keyboard shortcut #, you can use the keyboard to specify the constant, as shown in the following example:
The gcalctool application provides ten default constant values, as described in the following table:
|
Number |
Value |
Description |
|---|---|---|
C0 | 0.621 | Kilometer-to-mile conversion factor Multiply the current value in the display area by this constant, to convert from kilometers per hour to miles per hour. For example, 8 * Con C0 = 5. Divide the current value in the display area by this constant, to convert from miles per hour to kilometers per hour. For example, 5 / Con C0 = 8. |
C1 | 1.414213562 | Square root of 2 |
C2 | 2.718281828 | e |
C3 | 3.141592653 | pi |
C4 | 0.3937007 | Centimeter-to-inch conversion factor Multiply the current value in the display area by this constant, to convert from centimeters to inches. For example, 30 * Con C4 = 12. Divide the current value in the display area by this constant, to convert from inches to centimeters. For example, 12 / Con C4 = 30. |
C5 | 57.295779513 | Degrees in a radian |
C6 | 1048576 | 2 ^ 20 |
C7 | 0.0353 | Gram-to-ounce conversion factor Multiply the current value in the display area by this constant, to convert from grams to ounces. For example, 500 * Con C7 = 18. Divide the current value in the display area by this constant, to convert from ounces to grams. For example, 18 / Con C7 = 500. |
C8 | 0.948 | Kilojoule-to-British-thermal-unit conversion factor Multiply the current value in the display area by this constant, to convert from kilojoules to British thermal units. For example, 10 * Con C8 = 9.48. Divide the current value in the display area by this constant, to convert from British thermal units to kilojoules. For example, 9.48 / Con C8 = 10. |
C9 | 0.061 | Cubic-centimeter-to-cubic-inch conversion factor Multiply the current value in the display area by this constant, to convert from cubic centimeters to cubic inches. For example, 100 * Con C9 = 6.10. Divide the current value in the display area by this constant, to convert from cubic inches to cubic centimeters. For example, 6.10 / Con C9 = 100. |
You can overwrite the default constants to store your own constants.
To store a new constant or edit an existing constant, perform the following steps:
Click Con, then select Edit Constants from the popup menu.
In the Edit Constants dialog, select the constant that you want to overwrite or edit.
Click on the Value field, then enter the new value.
Click on the Description field, then enter the new description.
Click OK to save your changes and close the Edit Constants dialog.
To Use Functions
To show the available functions, click Fun. A popup menu displays the list of defined functions. Select a function from the menu to run that function.
If you use the keyboard shortcut F, you can use the keyboard to specify the function, as shown in the following example:
The gcalctool application does not provide any default functions. You can store up to ten functions.
To store a new function or edit an existing function, perform the following steps:
Click Fun, then select Edit Functions from the popup menu.
In the Edit Functions dialog, select a blank entry, or the function that you want to overwrite.
Click on the Value field, then enter the new equation to solve. You can use "ans" for the result of the previous equation and "R5" for register 5 etc. For example, enter (-R1+sqrt(R1^2-4*R0*R2))/(2*R0) to calculate a root of the quadratic equation R0*x^2 + R1*x + R2 = 0.
Click on the Description field, then enter the new description. For example, Quadratic Solver.
Click OK to save your changes and close the Edit Functions dialog.
To Perform Miscellaneous Scientific Calculations
To perform miscellaneous scientific calculations, use the buttons described in Table 11.
Table 11. Performing Miscellaneous Scientific Calculations
|
Function |
Button |
Description |
Example |
Result |
|---|---|---|---|---|
e to the x power | ex | Calculates the value of e raised to the power of the current value in the display area. | 2 ex | 7.39 |
10 to the x power | 10x | Calculates the value of 10 raised to the power of the current value in the display area. | 2 10x | 100 |
2 to the x power | 2x | Calculates the value of 2 raised to the power of the current value in the display area. | 2 2x | 4 |
x to the y power | xy | Raises the current value in the display area to the power of the next value that you enter. | 2 xy 4 = | 16 |
x to the reciprocal y power | x1/y | Raises the current value in the display area to the reciprocal power of the next value that you enter. | 2 x1/y 4 = | 16 |
x Factorial | x! | Calculates the factorial of the current value in the display area. x factorial is x*(x-1)*(x-2)...*1. This function applies only to positive integers. | 4 x! | 24 |
Modulus Division | Mod | Divides the current integer value in the display area by the next integer number that you enter, displaying the remainder. | 15 Mod 4 = | 3 |
Random Number Generator | Rand | Generates a random number in the range 0.0 to 1.0 then displays the random number in the display area. | Rand | 0.14 |
To Perform Programming Calculations
To change to Programming mode, choose View->Programming.
When you change to Programming mode, the following widget is displayed above the Base and Advanced mode buttons:
To Set the Numeric Base
To set the numeric base, select one of the buttons described in Table 12.
Table 12. Setting the Numeric Base
|
Function |
Button |
Description |
|---|---|---|
Binary Base | Bin | Sets the numeric base to binary, that is, base 2. |
Octal Base | Oct | Sets the numeric base to octal, that is, base 8. |
Decimal Base | Dec | Sets the numeric base to decimal, that is, base 10. Decimal is the default numeric base. If you change from Programming mode to another mode, gcalctool automatically sets the numeric base to decimal. |
Hexadecimal Base | Hex | Sets the numeric base to hexadecimal, that is, base 16. |
To Set the Word Length
The word length can be altered, to make the bitwise functions behave differently. To set the word length, select one of the buttons described in Table 13.
To Perform Bit Manipulations on Integers
If the calculator display shows an integer value, then each of the bits in that integer value is displayed as a collection of 0s and 1s in the Bit Editor. By clicking on any of these individual bits, their value can be toggled, causing the displayed integer value to be adjusted accordingly.
To Perform Bitwise Calculations
To perform bitwise calculations, use the buttons described in Table 14.
Table 14. Performing Bitwise Calculations
|
Function |
Button |
Description |
Example |
Result |
|---|---|---|---|---|
Bitwise OR | OR | Performs a bitwise OR operation on the current value in the display area and the next number that you enter. | 10001000 OR 00010001 | 10011001 |
Bitwise AND | AND | Performs a bitwise AND operation on the current value in the display area and the next number that you enter. | 10101010 AND 00110011 | 100010 |
Bitwise NOT | NOT | Performs a bitwise NOT operation on the current value in the display area, using the word size configured in the Section called To Set the Word Length. | NOT 1357ACE | FECA8531 |
Bitwise XOR | XOR | Performs a bitwise XOR operation on the current value in the display area and the next number that you enter. | 1100 XOR 1010 | 110 |
Bitwise XNOR | XNOR | Performs a bitwise XNOR operation on the current value in the display area and the next number that you enter. | 1100 XNOR 1010 | 1001 |
To Manipulate Binary Numbers
To manipulate binary numbers, use the buttons described in Table 15.
Table 15. Manipulating Binary Numbers
|
Function |
Button |
Description |
Example |
Result |
|---|---|---|---|---|
Left Shift n | < | Shifts the current value in the display area, the specified number of places to the left. Click <, then select the number of shift places from the popup menu. The number can be shifted up to 15 places left. | 111 < 1 place | 1110 |
Right Shift n | > | Shifts the current value in the display area, the specified number of places to the right. Click >, then select the number of shift places from the popup menu. The number can be shifted up to 15 places right. | 1011 > 1 place | 101 |
Truncating a number | Trunc | Truncates the current value in the display area to the word size configured in the Section called To Set the Word Length. | FFFFFFFFFF Trunc | FFFFFFFF |
Get the 1's complement | 1's | Calculates the 1's complement for the current value in the display area, using the word size configured in the Section called To Set the Word Length. | D723 1's | FFFF28DC |
Get the 2's complement | 2's | Calculates the 2's complement for the current value in the display area, using the word size configured in the Section called To Set the Word Length. | D723 2's | FFFF28DD |
If you use keyboard shortcuts, you can use the keyboard to specify the number of places to shift, as shown in the following examples:
To Perform Miscellaneous Programming Calculations
To perform miscellaneous programming calculations, use the buttons described in Table 16.
To Undo and Redo
To undo your previous action, choose Edit->Undo. You can undo up to 15 past actions.
If you want to redo an action you have just undone, choose Edit->Redo. You can redo up to 15 undone actions.
To Quit
To quit gcalctool, choose Calculator->Quit.
When you quit gcalctool, the current values of the following settings are stored and automatically applied the next time you start gcalctool:
Mode: Basic, Advanced, Financial, or Scientific
Memory Registers window displayed or not displayed, plus the contents of each memory register
Technical Information
Error Conditions
If you perform an invalid calculation, gcalctool indicates the error condition as follows:
Displays the word Error in the display area.
Displays an error message in the status bar.
Makes all calculator buttons unavailable, except Clr.
Makes all calculator options unavailable.
Makes all calculator menu items unavailable, except Calculator->Quit and Help->Contents.
To clear the error condition, click Clr or press Shift-Delete.
Changing Modes
If the user tries to change modes when a partial calculation is being displayed, a warning dialog is displayed, telling the user that the current calculation will be cleared, and the base will be reset to decimal.
There is a checkbox present, that if checked, prevents the dialog from being shown again.
If the user presses the Cancel button, the change mode operation is cancelled. If the user presses the Change Mode button, the mode is changed and has the following side-effects:
Clears the display.
Sets the base to decimal.
Sets the numeric display to fixed.
Sets the accuracy to nine places after the numeric point.
Clears the display of the thousands separator.
Clears the display of trailing zeroes after the numeric point.
Dismisses the register window if the new mode is Basic.
Changing The Display Area
It is possible to use the mouse to click on the display area and edit it.
All the normal keyboard shortcuts will work, plus the addition of:
Ctrl-Delete which will delete the character to the right of the text cursor
Home which moves the text cursor to the beginning of the display area
End which moves the text cursor to the end of the display area
Quick Reference: Keyboard Shortcuts
Table 17, Table 18, and Table 19 provide a quick reference for all of the gcalctool keyboard shortcuts.
When you use the keyboard shortcut for any of the calculator buttons that have a menu associated with them, that menu is displayed. You can then use the arrow keys to select a menu item or the menu item's shortcut.
Table 17. Quick Reference for Keyboard Shortcuts of gcalctool Buttons
Table 18. Quick Reference for Keyboard Shortcuts of gcalctool Scientific Mode Options
|
Keyboard Shortcut |
Option |
Function |
See |
|---|---|---|---|
Alt-1 | 16 bit | Set the word size to 16 bits. | |
Alt-3 | 32 bit | Set the word size to 32 bits. | |
Alt-6 | 64 bit | Set the word size to 64 bits. | |
Alt-a | Gradians | Set the trigonometric type to gradians. | |
Alt-b | Bin | Set the numeric base to binary. | |
Alt-d | Dec | Set the numeric base to decimal. | |
Alt-f | Fix | Set the display type to fixed-point format. | |
Alt-g | Degrees | Set the trigonometric type to degrees. | |
Alt-i | Inv | Select the inverse option for use with the trigonometric functions. | Table 8 in the Section called To Set the Trigonometric Options |
Alt-n | Eng | Set the display type to engineering format. | |
Alt-o | Oct | Set the numeric base to octal. | |
Alt-r | Radians | Set the trigonometric type to radians. | |
Alt-s | Sci | Set the display type to scientific format. | |
Alt-x | Hex | Set the numeric base to hexadecimal. | |
Alt-y | Hyp | Select the hyperbolic option for use with the trigonometric functions. | Table 8 in the Section called To Set the Trigonometric Options |
Table 19. Quick Reference for Keyboard Shortcuts of gcalctool Menu Items
|
Keyboard Shortcut |
Menu Item |
Function |
See |
|---|---|---|---|
Ctrl-b | View->Basic | Change to Basic mode | |
Ctrl-c | Edit->Copy | Copy the current value in the display area to the clipboard | |
Ctrl-f | View->Financial | Change to Financial mode | |
Ctrl-h | Help->Contents | Display the gcalctool online help | |
Ctrl-i | Edit->Insert ASCII Value | Display the Insert ASCII Value dialog | |
Ctrl-k | View->Show Thousands Separator | Display the thousands separator | |
Ctrl-m | View->Memory Registers | Display the Memory Registers window | |
Ctrl-p | View->Programming | Change to Programming mode | |
Ctrl-q | Calculator->Quit | Quit the gcalctool application | |
Ctrl-s | View->Scientific | Change to Scientific mode | |
Ctrl-t | View->Show Trailing Zeroes | Show trailing zeroes | |
Ctrl-v | Edit->Paste | Paste the current value in the clipboard to the display area | |
Ctrl-z | Edit->Undo | Undo previous action | |
Shift-Ctrl-z | Edit->Redo | Redo an undone action |