Checksum for tables

STEFHOLZ

Hi,

 

I want to create a unit test for a module which manipulates a table at many cells. So I thought to test against a checksum of the table

I could not find a function wich gives you a checksum for a table out-of-the-box.

 

Does anyone have neat idea how to do it?

 

Best regards

Stefan

Craige_Hales

I'd suggest using the BlobMD5 function. You might want to checksum the data inside the table rather than the table's disk image because JMP might add a date to the binary data on disk or even change the format in a future release. The first example is probably NOT what you want for a unit test.

 

// capture the md5 of the data the table saves to disk
Show(
	Hex(/* make it printable */
		Blob MD5(/* get the hash */
			Load Text File(
				"$SAMPLE_DATA/big class.jmp",
				BLOB/* the result is a BLOB, not a string */
			)
		)
	)
);

// capture the md5 of the script that will produce the table
dt = Open( "$SAMPLE_DATA/big class.jmp" );
Show( Hex( Blob MD5( Char To Blob( Char( dt << getscript ) ) ) ) );

// capture the md5 of some numeric columns in the table; avoids numeric to character conversions
Show( Hex( Blob MD5( Matrix To Blob( dt[0, {height, age, weight}], "float", 8, "little" ) ) ) );

// capture the md5 of some mixed columns in the table
Show( Hex( Blob MD5( Char To Blob( Char( dt[0, {name, height, age, weight}] ) ) ) ) );