External Interfaces Reference |
Get structure array field value, given field name and index
Fortran Syntax
Arguments
pm
Pointer to a structure mxArray
.
index
The desired element. The first element of an mxArray
has an index
of 1
, the second element has an index
of 2
, and the last element has an index
of N
, where N is the total number of elements in the structure mxArray
.
fieldname
The name of the field whose value you want to extract.
Returns
A pointer to the mxArray
in the specified field at the specified fieldname
, on success. Returns zero if passed an invalid argument or if there is no value assigned to the specified field. Common causes of failure include:
pm
that does not point to a structure mxArray
. To determine if pm
points to a structure mxArray
, call mxIsStruct
.
index
to an element past the end of the mxArray
. For example, given a structure mxArray
that contains 10 elements, you cannot specify an index
greater than 10.
fieldname
. Call mxGetFieldNameByNumber
to get existing field name
s.
mxArray
.
Description
Call mxGetField
to get the value held in the specified element of the specified field.
mxGetFieldByNumber
is similar to mxGetField
. Both functions return the same value. The only difference is in the way you specify the field. mxGetFieldByNumber
takes fieldnumber
as its third argument, and mxGetField
takes fieldname
as its third argument.
where index
is 1
if you have a one-by-one structure.
See Also
mxGetFieldByNumber
, mxGetFieldNameByNumber
, mxGetNumberOfFields
, mxIsStruct
, mxSetField
, mxSetFieldByNumber
mxGetEps | mxGetFieldByNumber |
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