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mxGetField

Get field value, given field name and index into structure array

C Syntax

Arguments

array_ptr
   Pointer to a structure mxArray.

index
   The desired element. The first element of an mxArray has an index of 0, the second element has an index of 1, and the last element has an index of N-1, where N is the total number of elements in the structure mxArray.

field_name
   The name of the field whose value you want to extract.

Returns

A pointer to the mxArray in the specified field at the specified field_name, on success. Returns NULL if passed an invalid argument or if there is no value assigned to the specified field. Common causes of failure include:

Description

Call mxGetField to get the value held in the specified element of the specified field. In pseudo-C terminology, mxGetField returns the value at

mxGetFieldByNumber is similar to mxGetField. Both functions return the same value. The only difference is in the way you specify the field. mxGetFieldByNumber takes field_num as its third argument, and mxGetField takes field_name as its third argument.

Calling

is equivalent to calling

where index is zero if you have a one-by-one structure.

See Also

mxGetFieldByNumber, mxGetFieldNameByNumber, mxGetFieldNumber, mxGetNumberOfFields, mxIsStruct, mxSetField, mxSetFieldByNumber


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