The input to qr is fixed.

[smkia]

Running demOilFgplvm7 demo results in the following error when calling fgplvmCreate.m:

Error using qr
Use qr(A,0) for economy size decomposition or use qr(A,'matrix') for a
permutation matrix and qr(A,'vector') for a permutation vector.

Error in gpUpdateAD (line 56)
      [Q, R] = qr([Ruu; sqrt(model.beta)*model.K_uf'],  '0');

Error in gpUpdateKernels (line 92)
model = gpUpdateAD(model, X);

Error in gpExpandParam (line 72)
  model = gpUpdateKernels(model, model.X, model.X_u);

Error in gpCreate (line 205)
model = gpExpandParam(model, initParams);

Error in fgplvmCreate (line 41)
model = gpCreate(q, d, X, Y, options);

This is because the second input to qr must be a either string with 'matrix' or 'vector' values, or scalar 0. While in the current version the input is string '0' (line 56 in gp/gpUpdateAD.m).
This pull request simply resolves the bug by changing '0' to scalar 0.