MATLAB POLYSPACE RELEASE NOTES Manual de usuario descargar pdf (Pagina 156)

4 Programming

Similarly, you can create a cell array from the name fields by enclosing the

list-generating expression within curly braces:

names = {S.name}

names =

'Ed Plum' 'Toni Miller' 'Jerry Garcia'

To assign the fields of each element of a structure array to separate variables

outside o f the structure, specify each output to the left of the equals sign,

enclosing them all within square brackets:

[N1 N2 N3] = S.name

N1 =

Ed Plum

N2 =

Toni Miller

N3 =

Jerry Garcia

Dynamic Field Names

The most common way to access the data in a structure is by specifying the

name of the field that you want to reference. A nother means of accessing

structure data is to use dynamic field names. These names express the

field as a variable expression that MATLAB evaluates at run-time. The

dot-parentheses syntax shown here makes

expression adynamicfieldname:

structName.(expression)

Index into this field using the standard MATLAB indexing syntax. For

example, to evaluate

expression into a field name and obtain the values of

that field at columns

1 through 25 of row 7,use

structName.(expression)(7,1:25)

Dynamic Field Nam es Exam pl e. The avgscore function shown b elow

computes an average test score, retrieving information from the

testscores

structure using dynamic field names:

function avg = avgscore(testscores, student, first, last)

for k = first: last

scores(k) = testscores.(student).w eek( k);

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MATLAB POLYSPACE RELEASE NOTES Manual de usuario Pagina 156