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C++ Mathematical Expression Library (ExprTk) http://www.partow.net/programming/exprtk/index.html

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Arash Partow
2013-07-28 21:35:06 +10:00
parent b369bc342c
commit 399a5f9aa3
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@ -134,9 +134,6 @@ include path (e.g: /usr/include/).
| := | Assign the value of x to y. (eg: y := x) |
| | Where y is a variable type. |
+----------+---------------------------------------------------------+
| <=> | Swap the values of x and y. (eg: x <=> y) |
| | Where both x and y are variables. |
+----------+---------------------------------------------------------+
(1) Equalities & Inequalities
+----------+---------------------------------------------------------+
@ -144,7 +141,7 @@ include path (e.g: /usr/include/).
+----------+---------------------------------------------------------+
| == or = | True only if x is strictly equal to y. (eg: x == y) |
+----------+---------------------------------------------------------+
| <> or != | True only if x does not equal y (eg: x <> y or x != y) |
| <> or != | True only if x does not equal y. (eg: x <> y or x != y) |
+----------+---------------------------------------------------------+
| < | True only if x is less than y. (eg: x < y) |
+----------+---------------------------------------------------------+
@ -152,7 +149,7 @@ include path (e.g: /usr/include/).
+----------+---------------------------------------------------------+
| > | True only if x is greater than y. (eg: x > y) |
+----------+---------------------------------------------------------+
| >= | True only if x greater than or equal to y (eg: x >= y) |
| >= | True only if x greater than or equal to y. (eg: x >= y) |
+----------+---------------------------------------------------------+
(2) Boolean Operations
@ -214,29 +211,29 @@ include path (e.g: /usr/include/).
+----------+---------------------------------------------------------+
| equal | Equality test between x and y using normalized epsilon |
+----------+---------------------------------------------------------+
| erf | Error function of x |
| erf | Error function of x. |
+----------+---------------------------------------------------------+
| erfc | Complimentary error function of x |
| erfc | Complimentary error function of x. |
+----------+---------------------------------------------------------+
| exp | e to the power of x |
| exp | e to the power of x. |
+----------+---------------------------------------------------------+
| expm1 | e to the power of x minus 1, where x is very small. |
| | (eg: expm1(x)) |
+----------+---------------------------------------------------------+
| floor | Largest integer that is less than or equal to x. |
+----------+---------------------------------------------------------+
| frac | Fractional portion of x |
| frac | Fractional portion of x. |
+----------+---------------------------------------------------------+
| hypot | Hypotenuse of x and y (eg: hypot(x,y) = sqrt(x*x + y*y))|
+----------+---------------------------------------------------------+
| log | Natural logarithm of x |
| log | Natural logarithm of x. |
+----------+---------------------------------------------------------+
| log10 | Base 10 logarithm of x |
| log10 | Base 10 logarithm of x. |
+----------+---------------------------------------------------------+
| log1p | Natural logarithm of 1 + x, where x is very small. |
| | (eg: log1p(x)) |
+----------+---------------------------------------------------------+
| log2 | Base 2 logarithm of x |
| log2 | Base 2 logarithm of x. |
+----------+---------------------------------------------------------+
| logn | Base N logarithm of x (eg: logn(1235,8)) |
| | where n > 0 and is an integer. |
@ -266,7 +263,7 @@ include path (e.g: /usr/include/).
| sum | Sum of all the inputs. |
| | (eg: sum(x,y,z,w,u,v,t) == (x + y + z + w + u + v + t)) |
+----------+---------------------------------------------------------+
| trunc | Integer portion of x |
| trunc | Integer portion of x. |
+----------+---------------------------------------------------------+
(4) Trigonometry Functions
@ -282,38 +279,38 @@ include path (e.g: /usr/include/).
| atan2 | Arc tangent of (x/y) expressed in radians. [-pi,+pi] |
| | eg: atan2(x,y) |
+----------+---------------------------------------------------------+
| cos | Cosine of x |
| cos | Cosine of x. |
+----------+---------------------------------------------------------+
| cosh | Hyperbolic cosine of x |
| cosh | Hyperbolic cosine of x. |
+----------+---------------------------------------------------------+
| cot | Cotangent of x |
| cot | Cotangent of x. |
+----------+---------------------------------------------------------+
| csc | Cosecant of x |
| csc | Cosecant of x. |
+----------+---------------------------------------------------------+
| sec | Secant of x |
| sec | Secant of x. |
+----------+---------------------------------------------------------+
| sin | Sine of x |
| sin | Sine of x. |
+----------+---------------------------------------------------------+
| sinh | Hyperbolic sine of x |
| sinh | Hyperbolic sine of x. |
+----------+---------------------------------------------------------+
| tan | Tangent of x |
| tan | Tangent of x. |
+----------+---------------------------------------------------------+
| tanh | Hyperbolic tangent of x |
| tanh | Hyperbolic tangent of x. |
+----------+---------------------------------------------------------+
| deg2rad | Convert x from degrees to radians |
| deg2rad | Convert x from degrees to radians. |
+----------+---------------------------------------------------------+
| deg2grad | Convert x from degrees to gradians |
| deg2grad | Convert x from degrees to gradians. |
+----------+---------------------------------------------------------+
| rad2deg | Convert x from radians to degrees |
| rad2deg | Convert x from radians to degrees. |
+----------+---------------------------------------------------------+
| grad2deg | Convert x from gradians to degrees |
| grad2deg | Convert x from gradians to degrees. |
+----------+---------------------------------------------------------+
(5) String Processing
+----------+---------------------------------------------------------+
| FUNCTION | DEFINITION |
+----------+---------------------------------------------------------+
| in | True only if x is a substring of y |
| in | True only if x is a substring of y. |
| | (eg: x in y or 'abc' in 'abcdefgh') |
+----------+---------------------------------------------------------+
| like | True only if the string x matches the pattern y. |
@ -471,59 +468,64 @@ correctly optimize such expressions for a given architecture.
(02) Standard mathematical operator precedence is applied (BEDMAS).
(03) Supported user defined types are numeric and string variables
(03) Results of expressions that are deemed as being 'valid' are to
exist within the set of Real numbers. All other results will be
of the value Not-A-Number (NaN).
(04) Supported user defined types are numeric and string variables
and functions.
(04) All variable and function names are case-insensitive
(05) All variable and function names are case-insensitive.
(05) Variable and function names must begin with a letter
(06) Variable and function names must begin with a letter
(A-Z or a-z), then can be comprised of any combination of
letters, digits and underscores. (eg: x, var1 or power_func99)
(06) Expression lengths and sub-expression lists are limited only by
(07) Expression lengths and sub-expression lists are limited only by
storage capacity.
(07) The life-time of objects registered with or created from a
specific symbol-table must span at least the life-time of
expressions generated using that symbol-table, otherwise
the result will be undefined behavior.
(08) The life-time of objects registered with or created from a
specific symbol-table must span at least the life-time of the
compiled expressions which utilize objects, such as variables,
of that symbol-table, otherwise the result will be undefined
behavior.
(08) Equal/Nequal are normalized equality routines, which use
(09) Equal/Nequal are normalized equality routines, which use
epsilons of 0.0000000001 and 0.000001 for double and float
types respectively.
(09) All trigonometric functions assume radian input unless
(10) All trigonometric functions assume radian input unless
stated otherwise.
(10) Expressions may contain white-space characters such as
(11) Expressions may contain white-space characters such as
space, tabs, new-lines, control-feed et al.
('\n', '\r', '\t', '\b', '\v', '\f')
(11) Strings may be constructed from any letters, digits or special
(12) Strings may be constructed from any letters, digits or special
characters such as (~!@#$%^&*()[]|=+ ,./?<>;:"`~_), and must
be enclosed with single-quotes.
eg: 'Frankly, my dear, I do not give a damn!'
(12) User defined normal functions can have up to 20 parameters,
(13) User defined normal functions can have up to 20 parameters,
where as user defined vararg-functions can have an unlimited
number of parameters.
(13) The inbuilt polynomial functions can be at most of degree 12.
(14) The inbuilt polynomial functions can be at most of degree 12.
(14) Where appropriate constant folding optimisations will be
(15) Where appropriate constant folding optimisations will be
applied. (eg: The expression '2+(3-(x/y))' becomes '5-(x/y)')
(15) String processing capabilities are available by default.
(16) String processing capabilities are available by default.
To turn them off, the following needs to be defined at
compile time: exprtk_disable_string_capabilities
(16) Composited functions can call themselves or any other functions
(17) Composited functions can call themselves or any other functions
that have been defined prior to their own definition.
(17) Recursive calls made from within composited functions will have
(18) Recursive calls made from within composited functions will have
a stack size bound by the stack of the executing architecture.
(18) Expressions may contain any of the following comment styles:
(19) Expressions may contain any of the following comment styles:
1. // .... \n
2. # .... \n
3. /* .... */