diff options
Diffstat (limited to '')
| -rw-r--r-- | ckt0.awk | 59 |
1 files changed, 36 insertions, 23 deletions
@@ -1,28 +1,24 @@ #!/usr/bin/env awk -f -function log10(n) { +function log10(n) { return log(n)/log(10.0) } - return log(n)/log(10.0) -} - - -function merge_meas(val_est, unc_est, val_meas, unc_meas) { +function merge_meas(est_val, est_unc, meas_val, meas_unc) { # Kalman filtering compares variances, - # convert uncerainties to square units - unc_est = (0.5*unc_est)^2.0 - unc_meas = (0.5*unc_meas)^2.0 + # convert uncertainties to square units + est_unc = (0.5*est_unc)^2.0 + meas_unc = (0.5*meas_unc)^2.0 - G_K = (unc_est)/((unc_est) + (unc_meas)) - val_est = val_est + G_K*(val_meas - val_est) - unc_est = (unc_est*unc_meas)/(unc_est + unc_meas) + K = (est_unc)/((est_unc) + (meas_unc)) + est_val = est_val + K*(meas_val - est_val) + est_unc = (est_unc*meas_unc)/(est_unc + meas_unc) - # convert unc_est back to original units - unc_est = 2.0*sqrt(unc_est) + # convert est_unc back to original units + est_unc = 2.0*sqrt(est_unc) - return sprintf(OFMT OFS OFMT ORS, val_est, unc_est) + return sprintf(OFMT OFS OFMT ORS, est_val, est_unc) } @@ -44,21 +40,41 @@ function sigfig(val, unc) { } +function ck_boottime() { + + "uname" | getline uname + close("uname") + + if (uname ~/OpenBSD/) { + "sysctl kern.boottime" | getline t0_k + close("sysctl kern.boottime") + sub("^.*=", "", t0_k) + split(t0_k, t0_k_arr) + t0_k_arr[2] = (index("JanFebMarAprMayJunJulAugSepOctNovDec", t0_k_arr[2]) + 2)/3.0 + gsub(":", " ", t0_k_arr[4]) + t0_k = sprintf("%04d %02d %02d %s", t0_k_arr[5], t0_k_arr[2], t0_k_arr[3], t0_k_arr[4]) + t0_k = mktime(t0_k) + } + + return t0_k + +} + + # function ck_boottime() { -# # "sysctl kern.boottime" | getline t_kboot # close("sysctl kern.boottime") # sub("^.*\{", "", t_kboot) # sub("\}.*$", "", t_kboot) # split(t_kboot, t_kboot_arr, ",") -# +# # for (i in t_kboot_arr) { # sub("^.*= ", "", t_kboot_arr[i]) # } -# +# # t_kboot = sprintf(t_kboot_arr[1] "." t_kboot_arr[2]) # return t_kboot -# +# # } @@ -141,15 +157,12 @@ BEGIN { # check ARGV for previous estimate if (ARGC > 0) { - ARGV[1] ? t0_est[1] = ARGV[1] : t0_est[1] = 0.0 + ARGV[1] ? t0_est[1] = ARGV[1] : t0_est[1] = ck_boottime() ARGV[2] ? t0_est[2] = ARGV[2] : t0_est[2] = systime() } #print("t0_est = ", t0_est[1]) #print("t_boot_unc = ", t0_est[2]) - # wait (sleep) based on uncertainty - # print(60.0/t0_est[2]) - # check uptime, update estimate print(ck_uptime(t0_est[1], t0_est[2])) |