### Common (Auxilary) functions

Auxilary functions which are used in different scripts.

 cp_SSgain_v000.m Computes a steady state gain for unobservable and uncontrollable navigation error models dc2dc_v000.m Given a discrete/continuous time DSR, converts it to continuous/discrete time DSR diagmat_v000.m Adds sub-matrices diagonally downsample_v000.m Downsamples the (imu) data by averaging it. (Imu data must not simply decimated to reduce data rate) imu_err_defs_v000.m Previously, I was using mdl_xxx functions to be able to seperate IMU error models from navigation models. I no longer follow that approach. Instead, I am going to put all error models in a single file and use it like a header file inside sys_xxx functions. Therefore, the new sys_xxx functions becomes dependent on the imu error model definitions which makes them unmodular. However, I found this approach much simpler for the users of the toolkit. imu_err_model_v000.m A script which converts imu_models into a standard model that can be directly used by sys_model scripts. Similar to imu_err_defs this is also model dependent. Whenever you add a new model to imu_err_defs, you must also add a corresponding cenversion routine in this script. interp_imu_v001.m Interpolate and syncronize the raw data (especially required for PDAs) lsmat_v001.m least squares (or ML for gaussian) solutions for linear models markov1st_v000.m discrete to/from continuous conversion for AR(1) models mat2vec_v000.m Symmetric matrix to/from vector conversion for covariance matrices. Especially used to save intermediate variables in smoothers. posdiff_v000.m Computes the metric position difference given 2 geodetic coordinates (i.e. latitude, longtitude, height) or $$C_e^n$$ matrix. readbin_v001.m Read binary files skew.m Given a vector, transforms it to a skew symmetric matrix ss2corr_v000.m Computes the correlation (matrix) sequence given a stable ss (A,B,C,D) model unskew.m Given skew symmetric matrix, transforms it to a vector