# MATLAB: Interpolation Error using interp1

interp1interpolationMATLAB

I'm using a script to take these x and y values from a .txt file. At this point in the script the variables are assigned the fid is closed… When I code further, I'm trying to interpolate a user entered value which is called 'userx'.
Below, though, I am just trying to get it to interpolate at 100. I don't understand where my syntax error is.
>> x
x =
           0          20          22          30          33          52          52          67          84         101         103         111         116         132         141         159         162         168         171         173
>> y
y =
        8477       11886       11384        6087        7871        3003        1941        9213       10981        2179        2219         507        1593        8880       11650        4392        6118        4437        2094        1961
>> interp1(x,y,100) Error using interp1 (line 130) Values must be of type double or single.
>>

x = x{:};y = y{:};