VBA-Expressions v3.1.2

Cleaning the house!

Improvements

• Better handling of function errors.

VBA-Expressions v3.1.1

Members changes

• VBAexpressions.cls: renamed ForceBoolean--> EnforceBoolean property

VBA-Expressions v3.1.0

A little bit more!

Improvements

• Added SUM function to aggregate the elements of a list.
• Added GET function to assign/retrieve variable values from expression arguments. Below is an example of detailed usage:

''' <summary>
'''     Variable assignments through parameters
''' </summary>
Private Sub GETfunctionExample()
    Dim expr As VBAexpressions
    
    Set expr = New VBAexpressions
    With expr
        .Create "GET('A';{{2;1;3};{3;-2;-1}}); GET('B';{{2;3};{1;-5};{-2;4}})": .Eval
        .Create "GET('C';MMULT(A;B))", False: .Eval 'Creates new expression without clean saved variables values
        .Create "ROUND(SUM(SIN(C[0;0]);SIN(C[1;1]));4)", False: .Eval
        Debug.Print "Sum sines of diagonal elements on matrix C: "; vbCr; .expression; "| Result: "; .result; " for: "; .CurrentVarValues
        Debug.Print "///////////////*****************////////////////////********************//////////////////*********************////////"
    End With
    Set expr = Nothing
End Sub
''' <OUTPUT>
''' 	Sum sines of diagonal elements on matrix C: 
''' 	ROUND(SUM(SIN(C[0;0]);SIN(C[1;1]));4)| Result: -0.1912 for: A = {{2;1;3};{3;-2;-1}}; B = {{2;3};{1;-5};{-2;4}}; C = {{-1;13};{6;15}}
''' 	///////////////*****************////////////////////********************//////////////////*********************////////
''' </OUTPUT>

• Added VarValue2 property. This property needs to be used to work with arrays variables assignments.
• Added an option to the Create method to allow users to create expressions without resetting variables.
• Library can already access elements within matrices. For example, the expression ROUND(SUM(SIN(A[0;0]);SIN(A[1;1]));4), with the matrix A={{-1;13};{6;15}} as a variable, performs the sum of sines for the diagonal elements of A with four digits precision, giving -0.1912 as result.
• Changed output behaviour of the equation solver and regression calculator. Results are now returned in a column vector.
• Refactored MMULT function.
• Formated procedures headers.

Bug fixes

• Row vectors were passed as a reference when column vectors were expected in functions involving matrix multiplications, such as the equation system solver and regression computation functions.

VBA-Expressions v3.0.1

One step higher!

Improvements

• Added MLR function for multiple linear regression over models with k regressors/predictors variables. The function supports two-way predictors interactions and named predictors.
• Added CHOLESKY function for decomposition of positive definite nxn matrices.
• Added CHOLSOLVE function for solving systems of linear equations by Cholesky decomposition.
• Added CHOLINVERSE function for computing inverse of matrices using the Cholesky decomposition.
• Added more unit tests.
• Removed unused code
• Improved ToDblArray method.
• Improved FIT function. Internally it now works with multiple linear regressions for polynomial fitting.
• Improved MSUM function.

Bug fixes

• Fixed bug preventing MMULT function from evaluating correctly when multiplying a 2D by 1D matrix.
• Fixed bug causing an anomalous splitting within the lists expressed as a literal string.

This release use ideas from:

(c) Douglas C. Montgomery and George C. Runger [Applied Statistics and Probability for Engineers]
(c) William H. Press [Numerical recipes in C: the art of scientific computing]

VBA-Expressions v3.0.0

The most robust expressions evaluation tool for VBA is here now!

Improvements

• Added ROUND function
• Added MROUND function for matrices elements round
• Added REM function to compute division operation remainder
• Added MSum function for matrices adittion and substraction
• Added MTranspose function for computing matrix transposition
• Added MNEG function for computing matrix negation
• Added GAMMALN function
• Added iBETA function for computing the integral of BETA function
• Added BETAINV function
• Added TINV_1T function for compute the one-tailed t-value (Student t-value) with up to 6 significant digits accuracy.
• Added TINV function to compute the one-tailed or two-tailed t-value (Student t-value) with up to 6 significant digits accuracy. Use the tOption parameter to select from two and right one-tailed computation.
• Added TINV_2T function compute the two-tailed t-value (Student t-value) with full significant digits accuracy.
• Added NORM function
• Added CHISQ function
• Added GAUSS function
• Added ERF function
• Added STUDT function
• Added ANORM function
• Added AGAUSS function
• Added AERF function
• Added ACHISQ function
• Added FISHF function
• Added ASTUDT function
• Added AFISHF function
• Added ArrayFromString2 method for create jagged arrays from Strings
• Added QR function for computing QR decomposition using Householder transformations.
• Added LSQRsolve function for solve overdetermined system of equations using the least square method and the QR decomposition.
• Added FIT function to perform least squares regression curve fitting with goodness of fit computation. The function supports straight-line, polynomial, exponentiation, power and logarithmic fits.
• New GAMMA function implementation
• More flexible variable scope: now allows vectors and arrays assignment from eval method directly. It is allowed to assign the value of a variable not present in the main expression but which is a second order variable present in the ImplicitVarValue arguments.
• More unit test added
• Aded support for matrices by scalar multiplication
• Improved string Array constructors and array parser
• Factorial function now accepts non integers parameters thanks to the new GAMMA function implementation
• Improved error messages for functions eval errors

Bug fixes

• Fixed bug preventing expressions from being parsed correctly at tokenisation stage.
• Fixed indexes base different from 0 for arrays.

Note

This software use ideas/creations from:
© John C. Pezzullo
© David M. Lane
© Dr. Hossein Arsham
© iCalculator™
© mozilla.org
© William H. Press [Numerical recipes in C: the art of scientific computing / William H. Press]

VBA-Expressions v2.0.2

• Fixed error: work with consecutive parentheses was broken.
• Added test for implied multiplication.

VBA-Expressions v2.0.1

This release add support for implicit multiplication, using parentheses, and for piecewise function evaluation.

VBA-Expressions v2.0.0

This new version includes many useful features, now VBA Expressions is shaping up to be a much more powerful tool.

Improvements

• VBA string, date-time and logical functions have been added (totaling more than 60 built-in functions).
• The evaluator now allows to define the value of a variable in terms of previously defined variables through the ImplicitVarValue property.
• Improved array handling mechanism.
• Added Solve and fZero functions.
• Refactoring: added VBAexpressionsScope class.
• Bug fixed: boolean negation prevents recognizing variables. Affected methods: Eval.

VBA-Expressions v1.0.1

Improvements:

• More advanced string manipulation behavior. It is now possible to evaluate string expressions as concat(concat('String1';'String2';'|');'String3';'+'). Note that Concat is a UDF function included to test the capabilities of our expression evaluator.
• The user can test the expression evaluator via a user form launched via a button from the Excel ribbon. This allows playing with the utility without the need to run Rubberduck unit tests.

VBA-Expressions v0.0.9

Bugs fixed:

• The system could not check for empty strings. Now users can check if a value is vbNullString using an expression like Date = ''.