Running the scipy.minimize function "I get TypeError: 'numpy.float64' object is not callable". Specifically during the execution of:
.../scipy/optimize/optimize.py", line 292, in function_wrapper
return function(*(wrapper_args + args))
I already looked at previous similar topics here and usually this problem occurs due to the fact that as first input parameter of .minimize is not a
function. I have difficulties in figure it out, because "a" is function.
What do you think?
### "data" is a pandas data frame of float values### "w" is a numpy float array i.e. [0.11365704 0.00886848 0.65302202 0.05680696 0.1676455 ]def a(data, w):### Return a negative float value from position [2] of an numpy array of float values calculated via the "b" function i.e -0.3632965490830499 return -b(data, w)[2]constraint = ({'type': 'eq', 'fun': lambda x: np.sum(x) - 1})### i.e ((0, 1), (0, 1), (0, 1), (0, 1), (0, 1))bound = tuple((0, 1) for x in range (len(symbols)))opts = scipy.minimize(a(data, w), len(symbols) * [1. / len(symbols),], method = 'SLSQP', bounds = bound, constraints = constraint)
Short answer
It should instead be:
opts = scipy.minimize(a, len(symbols) * [1. / len(symbols),], args=(w,), method='SLSQP', bounds=bound, constraints=constraint)
Details
a(data, w)
is not a function, it's a function call. In other words a(data, w)
effectively has the value and type of the return value of the function a
. minimize
needs the actual function without the call (ie without the parentheses (...)
and everything in-between), as its first parameter.
From the scipy.optimize.minimize
docs:
scipy.optimize.minimize(fun, x0, args=(), method=None, jac=None, hess=None, hessp=None, bounds=None, constraints=(), tol=None, callback=None, options=None)
...
fun : callable
The objective function to be minimized. Must be in the form f(x, *args). The optimizing argument, x, is a 1-D array of points, and args is a tuple of any additional fixed parameters needed to completely specify the function.
...
args : tuple, optional
Extra arguments passed to the objective function...
So, assuming w
is fixed (at least with respect to your desired minimization), you would pass it to minimize
via the args
parameter, as I've done above.