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#3zq(Bpwv"z CALC 2.0 by Bill Dimm Amiga Version August 7, 1990 The Amiga version of Calc may be distributed freely as long as no charge beyond a reasonable copying fee is made. This program is shareware - if you like it, you are encouraged to send me (a starving grad student :-) ) a donation. If you have any bugs to report, or any requests for features for the next version, please send them also. Bill Dimm Box 385 Springfield, PA. 19064-0385 DIMM@ANLPNS.BITNET DIMM@ANLPNS.PNS.ANL.GOV USAGE Usage1: CALC [options] Usage2: CALC [options] expression1 expression2 ... Usage3: CALC [options] -v var expression [file1 file2 ...] DESCRIPTION Calc is a shell style calculator. Calc does not have a fancy keypad display as many other calculator programs do. Instead, it is capable of taking its input from a file, the keyboard (stdin), or a command line and outputting its results to a file or the screen (stdout). It can also apply a single equation to all of the values stored in a file (or files). It handles all common mathematical expressions, can optionally predefine physical constants (see the options -m and -g and the commands mks and gaussian), and allows you to store values in the 26 variables a-z. If Calc is invoked using the format in Usage1, it will read mathematical expressions and commands from the keyboard or the input file (see option -i and command infile) and execute them until it encounters the exit command, or finds the end of the input file. If Calc is reading from the keyboard, it will display a prompt CALC> when it is waiting for a command or mathematical expression. The command or expression is evaluated when the return key is pressed. Expressions may be of any length, and case is ignored. The result of the evaluation of all mathematical expressions is displayed on the screen, or stored in a file (see option -o and the command outfile). When an error occurs, an error message is printed to the screen, or to a file (see option -e and the command errorfile), and Calc ignores the rest of the line and continues (unless the error is critical, in which case it exits). Calc can be told to exit automatically when any error occurs (see option -a and command aborterron). Comments can be added to a line by preceding them with a # . All input is buffered (unless buffering is turned off using the option -b or the command bufferoff) so that you can save your work at any point by using the save command. The format in Usage2 tells Calc to evaluate the commands/expressions on the command line instead of reading a file or the keyboard for commands/expressions. The commands/expressions used in this mode are not buffered, so they cannot be saved. Using Usage3 puts Calc in column mode. In this mode it will Page 1 evaluate the given expression once for each value stored in the specified files. var tells Calc what variable name to assign to the values in file1. var must be a single alphabetic character. The next alphabetic letter is assigned to the contents of file2, etc. If no files are specified, values are read from the keyboard (stdin) and assigned to var (you must terminate the input with an end of file which is generated by typing CTRL Z on VMS). Calc reads a value from each of the files, sets the corresponding variable, then evaluates the expression, and outputs the result. This process is repeated until Calc finds the end of one of the input files. Each value in the files must be separated from the others by whitespace (spaces, tabs, or carriage returns). MATHEMATICAL EXPRESSIONS Expressions conform to normal mathematical notation (note: you must use a * for multiplication, you cannot simply use parenthesis). They may be of any length, and case is ignored. All spaces and tabs are ignored. You can also store the results of a calculation by typing var=expression where var is any letter from a to z. For example, x = 4*sin(pi/3)/cosh(gamma(5)) Calc keeps track of the current value of each of the 26 variables, and the expressions which were used to define them. Normally, when a variable is defined, the expression is evaluated immediately and the result is stored as the current value of the variable. Calc can be told not to evaluate the expression immediately by using the -d or the command definitionevaloff. You may use any of the 26 variables in a mathematical expression. If you use a variable which has not been defined, a warning is printed and the value 0 is used. When a variable is used in an expression, Calc checks the definition of the variable and automatically updates the current value of the variable if necessary. For example: CALC> x=1 # This is a comment. 1 CALC> y=2 2 CALC> r=sqrt(x^2+y^2) 2.236067977499789 CALC> 1/r 0.447213595499958 CALC> x=2 2 CALC> 1/r 0.353553390593274 When a variable's definition includes a reference to itself, it's current value is used to compute a new value. For example: CALC> x=1 1 CALC> x=x+.5 1.5 CALC> x 2 CALC> x 2.5 To list the definitions and current values of all variables, use the list command. The following is a list of expressions which are supported by the FUNC library, which is responsible for evaluating Page 2 mathematical expressions in Calc. Any required explanation of the function/operator/constant is given. 'x' and 'y' are used to represent any legal expressions (or constants). All angles are in radians. x-y Binary minus -x Unary minus x+y Binary plus x%y Modulus - gives the remainder that results from dividing x by y x&y Logical AND - returns 1 if absolute value of both x & y is > EPS (ie. x and y are non-zero). 0 is returned otherwise. x*y Product of x and y x/y x divided by y x<y Returns 1 if x < y and 0 if x >= y x=y Returns 1 if the difference between x and y is < EPS x>y Returns 1 if x > y and 0 if x <= y x^y Gives x raised to the power y abs(x) Absolute value acos(x) Inverse cosine of x acosh(x) Inverse hyperbolic cosine acot(x) Inverse cotangent acoth(x) Inverse hyperbolic cotangent acsc(x) Inverse cosecant acsch(x) Inverse hyperbolic cosecant asec(x) Inverse secant asin(x) Inverse sine asinh(x) Inverse hyperbolic sine atan(x) Inverse tangent cos(x) Cosine cosh(x) Hyperbolic cosine cot(x) Cotangent coth(x) Hyperbolic cotangent csc(x) Cosecant csch(x) Hyperbolic cosecant eps Epsilon - a small number exp(x) Exponential: exp(x) = e^x gamma(x) Gamma function: gamma(x) = integral from t = 0 to infinity of t^(x-1)exp(-t)dt. Note that for positive integers, gamma(n+1) = n factorial, also denoted n!. Due to the fact that gamma(x) is computed by different methods for different values of x, gamma(x) may be discontinuous in places. lg(x) Base 2 logarithm ln(x) Natural logarithm (base e) log(x) Base 10 logarithm pi Pi sec(x) Secant sech(x) Hyperbolic secant sin(x) Sine sinh(x) Hyperbolic sine sqr(x) x squared (x*x) sqrt(x) Square root tan(x) Tangent tanh(x) Hyperbolic tangent x|y Logical OR. Gives 1 if the absolute value of either x or y is > eps. Gives 0 otherwise. Page 3 Note that there is some ambiguity about an expression such as x=2. Is this a definition, or an application of the equality operator? If Calc finds a variable as the first character on a line, and an = following it, it assumes that it is a definition. Thus, to force it to view the = as an equality operator instead of a definition, you could use (x=2). COMMANDS The following commands are recognized by Calc. aborterroff Tells Calc not to abort when it is capable of recovering from an error (this is the default). aborterron Tells Calc to abort when ANY error occurs. bufferoff Turns off the buffering of user input. Previously buffered input is not lost. The save command only saves input which has been buffered. bufferon Turns the buffering of user input on (this is the default). The save command only saves input which has been buffered. definitionevaloff Causes calc not to immediately update a variable when it is defined. This is useful when the definition relies on variables which have not been defined yet. definitionevalon Causes Calc to evaluate variable definitions immediately & update the current value of the variable (this is the default). errfile Prompts for the name of a file in which all error messages are deposited. exit Exits from Calc. gaussian Defines several of the variables with useful constants in the gaussian (centimeter, gram, second) system of units. Be warned that previous definitions of these variables will be destroyed. infile Prompts for the name of a file which will be used for input. list Lists the current values and definitions of all variables. Page 4 mks Defines several of the variables with useful constants in the mks (meter, kilogram, second) system of units. Be warned that previous definitions of these variables will be destroyed. outfile Prompts for the name of a file in which output is stored. promptoff Discontinues the displaying of CALC> when waiting for commands/expressions from the keyboard (stdin). prompton Tells Calc to display the prompt CALC> when it is waiting for commands/expressions from the keyboard (stdin). This is the default. quit Same as exit. repeatoff Tells Calc not to echo the input to the output channel (this is the default). repeaton Tells Calc to echo the input to the output channel. This is useful when the output is being directed to a file so that you can see both the expressions and their values. save Prompts for the name of a file in which the commands/expressions which have been entered previously are stored. OPTIONS -o NAME Stores all output in a file called NAME. -i NAME Uses the contents of the file NAME as input. -e NAME Stores all error messages in the file NAME. -a Same as the command aborterron. -b Same as the command bufferoff. -d Same as the command definitionevaloff. -g Same as the command gaussian. Page 5 -m Same as the command mks. -p Same as the command promptoff. -r Same as the command repeaton. EXAMPLES An example of Usage1: $ CALC CALC> x=5 5 CALC> y=2 2 CALC> sin(x)*y^4 -15.342788394610217 CALC> exit An example of Usage2: $ CALC 1+2/3 4/5 pi 1.666666666666667 0.8 3.141592653589793 As an example of Usage3, consider the two files: file1: 1 2 3 4 file2: 2 2.5 3 3.5 Then, envoking calc as follows: $ CALC -v x x^y file1 file2 1 5.656854249492377 27 127.9999999999999 Page 6