1mathfunc(n) Tcl Mathematical Functions mathfunc(n)
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6
8 mathfunc - Mathematical functions for Tcl expressions
9
11 package require Tcl 8.5
12 ::tcl::mathfunc::abs arg
14 ::tcl::mathfunc::acos arg
15 ::tcl::mathfunc::asin arg
16 ::tcl::mathfunc::atan arg
17 ::tcl::mathfunc::atan2 y x
18 ::tcl::mathfunc::bool arg
19 ::tcl::mathfunc::ceil arg
20 ::tcl::mathfunc::cos arg
21 ::tcl::mathfunc::cosh arg
22 ::tcl::mathfunc::double arg
23 ::tcl::mathfunc::entier arg │
24 ::tcl::mathfunc::exp arg
25 ::tcl::mathfunc::floor arg
26 ::tcl::mathfunc::fmod x y
27 ::tcl::mathfunc::hypot x y
28 ::tcl::mathfunc::int arg
29 ::tcl::mathfunc::isqrt arg
30 ::tcl::mathfunc::log arg
31 ::tcl::mathfunc::log10 arg
32 ::tcl::mathfunc::max arg ?arg ...?
33 ::tcl::mathfunc::min arg ?arg ...?
34 ::tcl::mathfunc::pow x y
35 ::tcl::mathfunc::rand
36 ::tcl::mathfunc::round arg
37 ::tcl::mathfunc::sin arg
38 ::tcl::mathfunc::sinh arg
39 ::tcl::mathfunc::sqrt arg
40 ::tcl::mathfunc::srand arg
41 ::tcl::mathfunc::tan arg
42 ::tcl::mathfunc::tanh arg
43 ::tcl::mathfunc::wide arg
44_________________________________________________________________
46
48 The expr command handles mathematical functions of the form sin($x) or
49 atan2($y,$x) by converting them to calls of the form [tcl::math‐
50 func::sin [expr {$x}]] or [tcl::mathfunc::atan2 [expr {$y}] [expr
51 {$x}]]. A number of math functions are available by default within the
52 namespace ::tcl::mathfunc; these functions are also available for code
53 apart from expr, by invoking the given commands directly.
54 Tcl supports the following mathematical functions in expressions, all
56 of which work solely with floating-point numbers unless otherwise
57 noted: abs acos asin atan
58 atan2 bool ceil cos cosh dou‐
59 ble entier exp floor fmod hypot int
60 isqrt log log10 max
61 min pow rand round
62 sin sinh sqrt srand tan tanh wide
63 In addition to these predefined functions, applications may define
65 additional functions by using proc (or any other method, such as interp
66 alias or Tcl_CreateObjCommand) to define new commands in the tcl::math‐
67 func namespace. In addition, an obsolete interface named Tcl_Cre‐
68 ateMathFunc() is available to extensions that are written in C. The
69 latter interface is not recommended for new implementations.
70 DETAILED DEFINITIONS
72 abs arg
73 Returns the absolute value of arg. Arg may be either integer or
74 floating-point, and the result is returned in the same form.
75 acos arg
77 Returns the arc cosine of arg, in the range [0,pi] radians. Arg
78 should be in the range [-1,1].
79 asin arg
81 Returns the arc sine of arg, in the range [-pi/2,pi/2] radians.
82 Arg should be in the range [-1,1].
83 atan arg
85 Returns the arc tangent of arg, in the range [-pi/2,pi/2] radi‐
86 ans.
87 atan2 y x
89 Returns the arc tangent of y/x, in the range [-pi,pi] radians.
90 x and y cannot both be 0. If x is greater than 0, this is
91 equivalent to “atan [expr {y/x}]”.
92 bool arg
94 Accepts any numeric value, or any string acceptable to string is
95 boolean, and returns the corresponding boolean value 0 or 1.
96 Non-zero numbers are true. Other numbers are false. Non-
97 numeric strings produce boolean value in agreement with string
98 is true and string is false.
99 ceil arg
101 Returns the smallest integral floating-point value (i.e. with a
102 zero fractional part) not less than arg. The argument may be
103 any numeric value.
104 cos arg
106 Returns the cosine of arg, measured in radians.
107 cosh arg
109 Returns the hyperbolic cosine of arg. If the result would cause
110 an overflow, an error is returned.
111 double arg
113 The argument may be any numeric value, If arg is a floating-
114 point value, returns arg, otherwise converts arg to floating-
115 point and returns the converted value. May return Inf or -Inf
116 when the argument is a numeric value that exceeds the floating-
117 point range.
118 entier arg
120 The argument may be any numeric value. The integer part of arg │
121 is determined and returned. The integer range returned by this │
122 function is unlimited, unlike int and wide which truncate their │
123 range to fit in particular storage widths.
124 exp arg
126 Returns the exponential of arg, defined as e**arg. If the
127 result would cause an overflow, an error is returned.
128 floor arg
130 Returns the largest integral floating-point value (i.e. with a
131 zero fractional part) not greater than arg. The argument may be
132 any numeric value.
133 fmod x y
135 Returns the floating-point remainder of the division of x by y.
136 If y is 0, an error is returned.
137 hypot x y
139 Computes the length of the hypotenuse of a right-angled triangle
140 “sqrt [expr {x*x+y*y}]”.
141 int arg
143 The argument may be any numeric value. The integer part of arg
144 is determined, and then the low order bits of that integer value
145 up to the machine word size are returned as an integer value.
146 For reference, the number of bytes in the machine word are
147 stored in tcl_platform(wordSize).
148 isqrt arg
150 Computes the integer part of the square root of arg. Arg must
151 be a positive value, either an integer or a floating point num‐
152 ber. Unlike sqrt, which is limited to the precision of a float‐
153 ing point number, isqrt will return a result of arbitrary preci‐
154 sion.
155 log arg
157 Returns the natural logarithm of arg. Arg must be a positive
158 value.
159 log10 arg
161 Returns the base 10 logarithm of arg. Arg must be a positive
162 value.
163 max arg ...
165 Accepts one or more numeric arguments. Returns the one argument
166 with the greatest value.
167 min arg ...
169 Accepts one or more numeric arguments. Returns the one argument
170 with the least value.
171 pow x y
173 Computes the value of x raised to the power y. If x is nega‐
174 tive, y must be an integer value.
175 rand Returns a pseudo-random floating-point value in the range (0,1).
177 The generator algorithm is a simple linear congruential genera‐
178 tor that is not cryptographically secure. Each result from rand
179 completely determines all future results from subsequent calls
180 to rand, so rand should not be used to generate a sequence of
181 secrets, such as one-time passwords. The seed of the generator
182 is initialized from the internal clock of the machine or may be
183 set with the srand function.
184 round arg
186 If arg is an integer value, returns arg, otherwise converts arg
187 to integer by rounding and returns the converted value.
188 sin arg
190 Returns the sine of arg, measured in radians.
191 sinh arg
193 Returns the hyperbolic sine of arg. If the result would cause
194 an overflow, an error is returned.
195 sqrt arg
197 The argument may be any non-negative numeric value. Returns a
198 floating-point value that is the square root of arg. May return
199 Inf when the argument is a numeric value that exceeds the square
200 of the maximum value of the floating-point range.
201 srand arg
203 The arg, which must be an integer, is used to reset the seed for
204 the random number generator of rand. Returns the first random
205 number (see rand) from that seed. Each interpreter has its own
206 seed.
207 tan arg
209 Returns the tangent of arg, measured in radians.
210 tanh arg
212 Returns the hyperbolic tangent of arg.
213 wide arg
215 The argument may be any numeric value. The integer part of arg
216 is determined, and then the low order 64 bits of that integer
217 value are returned as an integer value.
218
220 expr(n), mathop(n), namespace(n)
221
223 Copyright (c) 1993 The Regents of the University of California.
224 Copyright (c) 1994-2000 Sun Microsystems Incorporated.
225 Copyright (c) 2005, 2006 by Kevin B. Kenny <kennykb@acm.org>.
226Tcl 8.5 mathfunc(n)