MLEvalString

Evaluate MATLAB command in MATLAB

Syntax

= MLEvalString(command)

MLEvalString command

err = MLEvalString(command)

Description

= MLEvalString(command) specifies the MATLAB^® command for evaluation in the MATLAB workspace. Use this syntax when working in a worksheet cell.

MLEvalString command works in a VBA macro.

err = MLEvalString(command) returns the execution status when executing MLEvalString in a VBA macro.

Examples

Create Diagonal Matrix in Worksheet Cells

Enter the variable a into cell A1. Enter the numbers 1 through 5 into the range of cells from B1 through F1.

Assign the range of cells to variable a in MATLAB using MLPutMatrix. Enter this text in cell A3.

=MLPutMatrix(A1,B1:F1)

Use diag to create a matrix b, containing a diagonal using the five numbers in variable a. Enter this text in cell A5.

=MLEvalString("b = diag(a);")

Retrieve matrix b from MATLAB into Excel^® cell A9. Enter this text in cell A7.

=MLGetMatrix("b","A9")

The matrix with the diagonal appears in cells A9 through E13.

Create Diagonal Matrix in VBA Macro

Enter the variable a into cell A1. Enter the numbers 1 through 5 into the range of cells from B1 through F1.

Click the Developer tab in Microsoft^® Excel, and then click Visual Basic. The Visual Basic^® Editor window opens.

Insert a new module and enter this VBA code into the Code section of the window. This sample code assumes a macro named Diagonal. For details on working with modules, see Excel Help.

Sub Diagonal()

    MLPutMatrix "a", Range("B1:F1")
    MLEvalString "b = diag(a);"
    MLGetMatrix "b", "A3"
    MatlabRequest

End Sub

Run the macro by clicking Run Sub/UserForm (F5). The diagonal matrix appears in cells A3 through E7. For details on running macros, see Excel Help.

Return Error for Invalid Command

Enter the variable a into cell A1. Enter the numbers 1 through 5 into the range of cells from B1 through F1.

Click the Developer tab in Microsoft Excel, and then click Visual Basic. The Visual Basic Editor window opens.

Insert a new module and enter this invalid VBA code into the Code section of the window. This sample code assumes a macro named Diagonal. For details on working with modules, see Excel Help.

Sub Diagonal()

    Dim err As Variant

    MLPutMatrix "a", Range("B1:F1")
    err = MLEvalString("b = diag(2a);") 'Invalid code
    
    If err <> 0 Then
        MsgBox err
    End If

    MLGetMatrix "b", "A3"
    MatlabRequest

End Sub

Run the macro by clicking Run Sub/UserForm in the VBA toolbar. For details on running macros, see Excel Help.

This Spreadsheet Link™ error displays: #COMMAND!. To display MATLAB errors, see MLShowMatlabErrors.

Input Arguments

command — MATLAB command to evaluate

string

MATLAB command to evaluate, specified as a string. Enclose the string in double quotes. Or, enter the string in a cell without quotes and enter the corresponding cell reference without quotes as the input argument.

Example: "sum"

Example: A1

Output Arguments

err — Execution status

string | number

Execution status, returned as a string or number. If MLEvalString fails, then err is a string containing an error code or error message. Otherwise, the command executes successfully and err is 0.

By default when MLEvalString fails, err contains a standard Spreadsheet Link error, such as #COMMAND. To return MATLAB errors, execute MLShowMatlabErrors.

Tips

• The specified action alters only the MATLAB workspace and has no effect on the Microsoft Excel workspace.

• To work with VBA code in Excel with Spreadsheet Link, you must enable Spreadsheet Link as a reference in the Microsoft Visual Basic Editor. For details, see Installation.