xbee is not sending decimal data

i'm trying t send decimal values to the audino wirelesly using xbee but audino does understand it. it tried this code

s=serial(s,'com5')

fopen(s)

fwrite(s,100)

xbee attached to the computer send the data and receving xbee that is attached to the audino recevies it

but audino does under stand it.

but when i send charter audino understand it. can u help me plz

s=serial(s,'com5')

fopen(s)

fwrite(s,'a')

[Ryan Livingston]

What happens when the "arduino does not understand it"? Are there errors?

Also, what datatype is the arduino expecting? Calling FWRITE without a precision argument passes a double:

http://www.mathworks.com/help/matlab/ref/serial.fwrite.html?searchHighlight=fwrite