External Interfaces Reference |
Get structure array field number, given field name
Fortran Syntax
Arguments
pm
Pointer to a structure mxArray
.
fieldname
The name of a field in the structure mxArray
.
Returns
The field number of the specified fieldname,
on success. The first field has a field number of 1
, the second field has a field number of 2
, and so on. Returns 0
on failure. Common causes of failure include:
pm
that does not point to a structure mxArray
. Call mxIsStruct
to determine if pm
points to a structure mxArray
.
fieldname
of a nonexistent field.
Description
If you know the name of a field but do not know its field number, call mxGetFieldNumber
. Conversely, if you know the field number but do not know its field name, call mxGetFieldNameByNumber
.
For example, consider a MATLAB structure initialized to
patient.name = 'John Doe'; patient.billing = 127.00; patient.test = [79 75 73; 180 178 177.5; 220 210 205];
The field name
has a field number of 1
; the field billing
has a field number of 2
; and the field test
has a field number of 3
. If you call mxGetFieldNumber
and specify a field name of anything other than 'name'
, 'billing'
, or 'test'
, then mxGetFieldNumber
returns 0
.
where index
is 1
if you have a 1
-by-1
structure.
See Also
mxGetField
, mxGetFieldByNumber
, mxGetFieldNameByNumber
, mxGetNumberOfFields
, mxSetField
, mxSetFieldByNumber
mxGetFieldNameByNumber | mxGetImagData |
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