N ν ⁡ ( x ) ⁢ e i ⁢ ϕ ν ⁡ ( x ) = ker ν ⁡ x + i ⁢ kei ν ⁡ x N_{\nu }\left(x\right)e^{i\phi _{\nu }\left(x\right)}=\operatorname {ker} _{\nu }x+i\operatorname {kei} _{\nu }x