matlab datastore using transform order and using user defined fction

i am using the datastore() to store some excel files , and i want to do some transforms an the data , like replace nan with 0 , i used transform(datastore,@fction) but it doesn't work good , in the fction i used my defined fction that should replace nan with 0 in table ,can maybe somebody help me , i think that i have synthax error , in transform ? Thank you

[dpb]

Well, we can't see/spot any syntax errors w/o the code used and the error(s) you got...

Are the files all numeric? If there's other than numeric data in the files as is so ofthen the case with spreadsheets, the function will probably fail unless you accounted for that somehow.