Phase-resolved properties of 4U 1954+319 over two pulse cycles. The PD and PA measurements derive from two methods: blue points show spectro-polarimetric analysis results, and square red symbols show model-independent measurements obtained with ixpepolarization. Panels display (a) the normalized pulse profile in the 2–8 keV band derived from the IXPE data, (b)–(c) the Stokes parameters q and u, (d) the PD, and (e) the PA. The PA panel shows two RVM solutions from Table 3, corresponding to two distinct posterior clusters in Fig. 6: Solution 1 (orange) and Solution 2 (green).