Truncating Decimal points of an array

I have imported some data into matlab that contains an accuracy that
is way too high for me to accurately search for a specific value
inside that variable.

For example, I am trying to find certain points in the datastring and
figuring out in what position it is inside the array. (I am searching
for ~23, data in the array is 23.0040209243929292 thus it cannot find

Is there a way to truncate the values down to a certain accuracy (say
4 decimal points?)

Strread seems to do what I want, but only for a string and not an
imported array.