Check validity of connectivity argument


iptcheckconn(conn, func_name, var_name, arg_pos)


iptcheckconn(conn, func_name, var_name, arg_pos) checks whether conn is a valid connectivity argument. If it is invalid, the function issues a formatted error message.

This function supports code generation (see Tips).

A connectivity argument can be one of the following scalar values: 1, 4, 6, 8, 18, or 26. A connectivity argument can also be a 3-by-3-by- ... -by-3 array of 0's and 1s. The central element of a connectivity array must be nonzero and the array must be symmetric about its center.

func_name is a string that specifies the name used in the formatted error message to identify the function checking the connectivity argument.

var_name is a string that specifies the name used in the formatted error message to identify the argument being checked.

arg_pos is a positive integer that indicates the position of the argument being checked in the function argument list. iptcheckconn includes this information in the formatted error message.

Class Support

conn must be of class double or logical and must be real and nonsparse.


Create a 4-by-4 array and pass it as the connectivity argument.

iptcheckconn(eye(4), 'func_name','var_name',2)

More About

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  • This function supports the generation of C code using MATLAB® Coder™. The code generated for this function uses a precompiled, platform-specific shared library. Use of a shared library preserves performance optimizations but limits the target platforms for which code can be generated. For more information, see Understanding Code Generation with Image Processing Toolbox.

    When generating code, all input arguments must be compile-time constants.

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