Taking maximum of R2 to choose hyperparameters causes an error if the maximum is not unique

[lucasschn]

With the given data, taking the hyperparameters yielding the best R2 score as in:
index = numpy.where(param_results[:, 0] == numpy.amax(param_results[:, 0])) # Maximum des R2

will cause the following line to raise an error on conversion to float:
best_out = model_energy_demand(wz_out, float(param_results[index, 1]), float(param_results[index, 2]), float(param_results[index, 3]), dfAnwend, True, True, 0.25)

The error is:
TypeError: only size-1 arrays can be converted to Python scalars

Indeed, index is not a scalar, causing param_results[index, 1] not to be a scalar either:

print(index)
(array([  66,   67,   68,   69,   70,   71,   72,   73,   74,   75,   76,
         187,  188,  189,  190,  191,  192,  193,  194,  195,  196,  197,
         308,  309,  310,  311,  312,  313,  314,  315,  316,  317,  318,
         429,  430,  431,  432,  433,  434,  435,  436,  437,  438,  439,
         550,  551,  552,  553,  554,  555,  556,  557,  558,  559,  560,
         671,  672,  673,  674,  675,  676,  677,  678,  679,  680,  681,
         792,  793,  794,  795,  796,  797,  798,  799,  800,  801,  802,
         913,  914,  915,  916,  917,  918,  919,  920,  921,  922,  923,
        1034, 1035, 1036, 1037, 1038, 1039, 1040, 1041, 1042, 1043, 1044,
        1155, 1156, 1157, 1158, 1159, 1160, 1161, 1162, 1163, 1164, 1165,
        1276, 1277, 1278, 1279, 1280, 1281, 1282, 1283, 1284, 1285, 1286]),)

Suggested solution
Take the first index only