sm

README

sm

symbolic math on Go

Documentation:

// Sexpr - simplification of expression.
// Example:
//
//	expr : "b*(2+3-1+8*a)",
//	out  : "4.000*b + 8.000*(a*b)",
//
//	expr: "d(2*pow(x,a),x);constant(a);variable(x);",
//	out:  "2.000*(a*pow(x,a - 1.000))",
//
// Keywords:
//
//	constant(a); for constants
//	variables(a); for variables
//  function(a,x,y,z,...); for function a(x,y,z)
//
func Sexpr(o io.Writer, expr string) (out string, err error) {

Example:

func Example() {
	eq, err := sm.Sexpr(os.Stdout, "-1+(-a)+(+5)+(+2+3+1)")
	if err != nil {
		panic(err)
	}
	fmt.Fprintf(os.Stdout, "%s", eq)
	// Output:
	// 5 + (-1 + (-a)) + (+2 + 3 + 1)
	// 5.000 + (-1 + (-a)) + (+2 + 3 + 1)
	// 5.000 + (-1 - a) + (+2 + 3 + 1)
	// 5.000 + (-1.000 - a) + (+2 + 3 + 1)
	// (5.000 + -1.000) - (a) + (+2 + 3 + 1)
	// 4.000 - (a) + (+2 + 3 + 1)
	// 4.000 - a + (+2 + 3 + 1)
	// 4.000 - a + (1 + (+2 + 3))
	// 4.000 - a + (1.000 + (+2 + 3))
	// 4.000 - a + (1.000 + 5.000)
	// 4.000 - a + 6.000
	// (6.000 + 4.000) - (a)
	// 10.000 - (a)
	// 10.000 - a
	// 10.000 - a
	// 10.000 - a
}

Documentation

Overview

Example

input := "-1+(-a)+(+5)+(+2+3+1)"
fmt.Fprintf(os.Stdout, "Input : %s\n\n", input)
eq, err := Sexpr(os.Stdout, input)
if err != nil {
	panic(err)
}
fmt.Fprintf(os.Stdout, "Output : %s\n", eq)

Output:

Input : -1+(-a)+(+5)+(+2+3+1)

-1.000 - a + 5.000 + (2.000 + 3 + 1)
4.000 + -a + (2.000 + 3 + 1)
4.000 - a + (2.000 + 3 + 1)
4.000 - a + (2.000 + 3.000 + 1)
4.000 - a + (5.000 + 1)
4.000 - a + (5.000 + 1.000)
4.000 - a + 6.000
10.000 + -a
10.000 - a

Output : 10.000 - a

Index

• Variables
• func Sexpr(o io.Writer, expr string) (out string, err error)

Examples

• Package

Variables

var FloatFormat int = 3

FloatFormat is format of float value, for more precision calculation use value equal 12.

var MaxIteration int64 = 1000000

Functions

func Sexpr

func Sexpr(o io.Writer, expr string) (out string, err error)

Sexpr - simplification of expression. Example:

expr : "b*(2+3-1+8*a)",
out  : "4.000*b + 8.000*(a*b)",

expr: "d(2*pow(x,a),x);constant(a);variable(x);",
out:  "2.000*(a*pow(x,a - 1.000))",

expr: "b*(2+8*a)*a; constant(a); constant(b)",
out:  "2.000*(a*b) + 8.000*(a*(a*b))",

expr: "(a + b) * (c - d - s); constant(a,b,c,d,s)",
out:  "a*c-a*d-a*s+(b*c-b*d-b*s)",

expr: "pow(a,5-3+1)",
out:  "a * (a * a)",

expr: "pow(a+1,2)",
out:  "1.000+2.000*a+a*a",

expr: "b*d(a*x,x);constant(a);variable(x);",
out:  "a * b",

expr: "d(2*pow(x,a),x);constant(a);variable(x);",
out:  "2.000*(a*pow(x,-1.000+a))",

expr: "d(u + v,x);function(u,x);function(v,x);",
out:  "d(u,x) + d(v,x)",

expr: "(a/b)/(c/d)",
out:  "a * d / (b * c)",

expr: "matrix(2+5,1,1)",
out:  "matrix(7.000,1.000,1.000)",

expr: "matrix(2+5,9,3, 5-1+0-0,2,2)*matrix(1-2,+5,2,1)",
out:  "matrix(38.000,17.000,2.000,1.000)",

expr: "integral(1,x,0,1);variable(x)",
out:  "1.000",

expr: "integral(1,x,2,4)*a;variable(x)",
out:  "2.000*a",

expr: "det(matrix(-1,1.5,1,-1,2,2))",
out:  "-0.500",

expr: "inverse(matrix(1,2,3,0,1,4,5,6,0,3,3))",
out:  "matrix(-24.000,18.000,5.000,20.000,-15.000,-4.000,-5.000,4.000,1.000,3.000,3.000)",

Keywords:

	constant(a); for constants
	variables(a); for variables
 function(a,x,y,z,...); for function a(x,y,z)