Error in lsqcurvefit (line 225)

I am absolutely new to the matlab.

i have 2 vectors,

xdata is 744x1 double

ydata is 744x1 double

my function is

function ydata=calcor(k,xdata)
ydata=(1-(1-k)*(xdata.^k));
end

i am trying to get k

k= lsqcurvefit(@calcor,[0 0],xdata,ydata)

it giving me error:

Error using .^

Matrix dimensions must agree.

Error in calcor (line 2)

ydata=(1-(1-k)*(xdata.^k));

Error in lsqcurvefit (line 225)

initVals.F = feval(funfcn_x_xdata{3},xCurrent,XDATA,varargin{:});

Caused by:

Failure in initial objective function evaluation. LSQCURVEFIT cannot continue.

whats is wrong with the code

[Mathieu NOE]

We know that k must be a scalar , but is it ? check its size

Answer 1

[Torsten]

x0 = 0, not x0 = [0 0].

[Batula]

@Torsten with a slight change of yours it worked! thank you very much for helping us