Reference - Revision history

Jrheinlaender: Page deleted

2017-07-09T18:01:29Z

Page deleted

Jrheinlaender: /* QUANTITY ( expression ) */

2017-01-15T12:35:38Z

QUANTITY ( expression )

← Older revision		Revision as of 12:35, 15 January 2017
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	==== <code>QUANTITY ( expression )</code> ====		==== <code>QUANTITY ( expression )</code> ====
	Try to find a quantity (number with optional units) for the expression from any equations defined previously in the document. Gives an error if the expression does not evaluate to a quantity.		Try to find a quantity (number with optional units) for the expression from any equations defined previously in the document. Gives an error if the expression does not evaluate to a quantity.

			All numerical values will be converted to floating point numbers. If you do not want this, use <code>VAL</code> instead.

	==== <code>QUANTITYWITH ( expression, eqlist )</code> ====		==== <code>QUANTITYWITH ( expression, eqlist )</code> ====

Jrheinlaender: /* VAL ( expression ) */

2017-01-15T12:34:55Z

VAL ( expression )

← Older revision		Revision as of 12:34, 15 January 2017
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	==== <code>VAL ( expression )</code> ====		==== <code>VAL ( expression )</code> ====
	Try to find a numeric value for the expression from any equations defined previously in the document.		Try to find a numeric value for the expression from any equations defined previously in the document.

			The expression will contain rational numbers, not floats, unless a conversion to a floating point number is required to fully evaluate the expression.

	==== <code>VALWITH ( expression, eqlist )</code> ====		==== <code>VALWITH ( expression, eqlist )</code> ====

Jrheinlaender: /* SIMPLIFY ( equation|expression, "simplification"; "simplification" ... ) */

2017-01-15T11:07:27Z

SIMPLIFY ( equation|expression, "simplification"; "simplification" ... )

← Older revision		Revision as of 11:07, 15 January 2017
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	* <code>collect-common</code> Collect common factors (see description of GiNaC collect_common_factors() method for details).		* <code>collect-common</code> Collect common factors (see description of GiNaC collect_common_factors() method for details).
	* <code>unsafe</code> Does unsafe simplifications, for example <code>sqrt{x^2} => x</code> or <code>\arctan\tan{x} => x</code>. Note that the opposite <code>\tan\arctan{x} => x</code> is not an unsafe evaluation and is thus done automatically (by GiNaC).		* <code>unsafe</code> Does unsafe simplifications, for example <code>sqrt{x^2} => x</code> or <code>\arctan\tan{x} => x</code>. Note that the opposite <code>\tan\arctan{x} => x</code> is not an unsafe evaluation and is thus done automatically (by GiNaC).
			* <code>ignore-units</code> Removes units from certain functions, so that scientific formulas evaluate properly. Currently only units in the arguments of <code>log</code> and <code>ln</code> are handled.
	* <code>diff</code> Evaluates differential function diff, thus symbolically calculating differentials as far as possible.		* <code>diff</code> Evaluates differential function diff, thus symbolically calculating differentials as far as possible.
	* <code>sum</code> Evaluates sum functions, thus symbolically calculating sums as far as possible.		* <code>sum</code> Evaluates sum functions, thus symbolically calculating sums as far as possible.

Jrheinlaender: /* Elements */

2016-12-17T18:51:34Z

Elements

← Older revision		Revision as of 18:51, 17 December 2016
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	* <code>equation</code> A relation which has the form <code>expression1 operator expression2</code>. Operator can be <code>=</code>, <code>></code> etc.		* <code>equation</code> A relation which has the form <code>expression1 operator expression2</code>. Operator can be <code>=</code>, <code>></code> etc.

			* <code>modular equation</code> A relation which has the form <code>expression1 EQUIV expression2 MOD expression3</code>. The modulus will be automatically applied on any integers in the equation whenever the equation changes.

	* <code>eqlist = equation; equation... </code> A list of equations, separated by semicolons		* <code>eqlist = equation; equation... </code> A list of equations, separated by semicolons

Jrheinlaender: /* @label@ { options } EQDEF * expression EQUIV expression MOD expression */

2016-12-17T18:49:24Z

@label@ { options } EQDEF * expression EQUIV expression MOD expression

← Older revision		Revision as of 18:49, 17 December 2016
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	==== <code>@label@ { options } EQDEF * expression</code> ====		==== <code>@label@ { options } EQDEF * expression</code> ====
	Define an equation. The expression most be of the form <code>expression1 = expression2</code>. For the special case of the equation label starting with <code>lib:</code>, the equation will not be erased by <code>CLEAREQUATIONS</code>. This is useful for building a library of generic equations, as for example in the file substitutions.imath.		Define an equation. The expression most be of the form <code>expression1 = expression2</code>. For the special case of the equation label starting with <code>lib:</code>, the equation will not be erased by <code>CLEAREQUATIONS</code>. This is useful for building a library of generic equations, as for example in the file substitutions.imath.

	~~==== <code>@label@ { options } EQDEF * expression EQUIV expression MOD expression</code> ====~~
	~~Define an equation with integer numbers and a modulus. The modulus will be applied automatically whenever the equation changes.~~

	==== <code>@label@ { options } CONSTDEF * expression</code> ====		==== <code>@label@ { options } CONSTDEF * expression</code> ====

Jrheinlaender: /* @label@ { options } EQDEF * expression */

2016-12-17T18:45:32Z

@label@ { options } EQDEF * expression

← Older revision		Revision as of 18:45, 17 December 2016
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	==== <code>@label@ { options } EQDEF * expression</code> ====		==== <code>@label@ { options } EQDEF * expression</code> ====
	Define an equation. The expression most be of the form <code>expression1 = expression2</code>. For the special case of the equation label starting with <code>lib:</code>, the equation will not be erased by <code>CLEAREQUATIONS</code>. This is useful for building a library of generic equations, as for example in the file substitutions.imath.		Define an equation. The expression most be of the form <code>expression1 = expression2</code>. For the special case of the equation label starting with <code>lib:</code>, the equation will not be erased by <code>CLEAREQUATIONS</code>. This is useful for building a library of generic equations, as for example in the file substitutions.imath.

			==== <code>@label@ { options } EQDEF * expression EQUIV expression MOD expression</code> ====
			Define an equation with integer numbers and a modulus. The modulus will be applied automatically whenever the equation changes.

	==== <code>@label@ { options } CONSTDEF * expression</code> ====		==== <code>@label@ { options } CONSTDEF * expression</code> ====

Jrheinlaender: PREFIXDEF

2016-11-11T17:40:17Z

PREFIXDEF

← Older revision		Revision as of 17:40, 11 November 2016
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	==== <code>UNITDEF { "unitname", symbol = expression }</code> ====		==== <code>UNITDEF { "unitname", symbol = expression }</code> ====
	Defines a new unit. The symbol is the name of the unit, this must begin with a percent sign % to distinguish it from a variable name. The expression defines the unit in terms of units already known to iMath. If this expression contains data types apart from units, powers of units, numerics, or constants already known to iMath, a warning is issued, but the unit definition is created anyway. The unitname is optional and gives a string to be printed instead of the symbol. This is useful when defining units whose name is not a valid symbol, e.g. inches: <nowiki>UNITDEF{"''", %inch = 0.0254 %m}</nowiki>.		Defines a new unit. The symbol is the name of the unit, this must begin with a percent sign % to distinguish it from a variable name. The expression defines the unit in terms of units already known to iMath. If this expression contains data types apart from units, powers of units, numerics, or constants already known to iMath, a warning is issued, but the unit definition is created anyway. The unitname is optional and gives a string to be printed instead of the symbol. This is useful when defining units whose name is not a valid symbol, e.g. inches: <nowiki>UNITDEF{"''", %inch = 0.0254 %m}</nowiki>.

			==== <code>PREFIXDEF { symbol = expression }</code> ====
			Defines a new unit prefix. The symbol is the name of the prefix, this must begin with a percent sign % to distinguish it from a variable name. The expression defines the numeric value of the prefix. Example: With the definition <nowiki>PREFIXDEF{%milli = 10^{-3}}</nowiki> iMath will automatically recognize the unit <nowiki>%millimetre</nowiki>.

	==== <code>REALVARDEF symbol</code> ====		==== <code>REALVARDEF symbol</code> ====

Jrheinlaender: REALVARDEF and POSVARDEF

2016-05-30T18:47:46Z

REALVARDEF and POSVARDEF

← Older revision		Revision as of 18:47, 30 May 2016
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	==== <code>UNITDEF { "unitname", symbol = expression }</code> ====		==== <code>UNITDEF { "unitname", symbol = expression }</code> ====
	Defines a new unit. The symbol is the name of the unit, this must begin with a percent sign % to distinguish it from a variable name. The expression defines the unit in terms of units already known to iMath. If this expression contains data types apart from units, powers of units, numerics, or constants already known to iMath, a warning is issued, but the unit definition is created anyway. The unitname is optional and gives a string to be printed instead of the symbol. This is useful when defining units whose name is not a valid symbol, e.g. inches: <nowiki>UNITDEF{"''", %inch = 0.0254 %m}</nowiki>.		Defines a new unit. The symbol is the name of the unit, this must begin with a percent sign % to distinguish it from a variable name. The expression defines the unit in terms of units already known to iMath. If this expression contains data types apart from units, powers of units, numerics, or constants already known to iMath, a warning is issued, but the unit definition is created anyway. The unitname is optional and gives a string to be printed instead of the symbol. This is useful when defining units whose name is not a valid symbol, e.g. inches: <nowiki>UNITDEF{"''", %inch = 0.0254 %m}</nowiki>.

			==== <code>REALVARDEF symbol</code> ====
			Defines the symbol to be real-valued. This allows iMath to evaluate some functions immediately (e.g. complex conjugation).

			==== <code>POSVARDEF symbol</code> ====
			Defines the symbol to be positive (and real-valued). This allows iMath to evaluate some functions immediately (e.g. absolute value).

	==== <code>VECTORDEF symbol</code> ====		==== <code>VECTORDEF symbol</code> ====

Jrheinlaender: /* VALWITH ( expression, expression; expression; ... ) */

2016-04-23T19:13:19Z

VALWITH ( expression, expression; expression; ... )

← Older revision		Revision as of 19:13, 23 April 2016
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	Try to find a numeric value for the expression from any equations defined previously in the document.		Try to find a numeric value for the expression from any equations defined previously in the document.

	==== <code>VALWITH ( expression, ~~expression; expression; ...~~ )</code> ====		==== <code>VALWITH ( expression, eqlist )</code> ====
	Try to find a numeric value for the expression from any equations defined previously in the document, plus the equations given as the second argument. These will be removed again after the value search, so they have no effect on the rest of the document.		Try to find a numeric value for the expression from any equations defined previously in the document, plus the equations given as the second argument. These will be removed again after the value search, so they have no effect on the rest of the document.