diff --git a/src/algorithms/libs/rtklib/rtklib_ephemeris.cc b/src/algorithms/libs/rtklib/rtklib_ephemeris.cc
index 70d124074..23b982091 100644
--- a/src/algorithms/libs/rtklib/rtklib_ephemeris.cc
+++ b/src/algorithms/libs/rtklib/rtklib_ephemeris.cc
@@ -90,7 +90,7 @@ double var_uraeph(int ura)
             2.4, 3.4, 4.85, 6.85, 9.65, 13.65, 24.0, 48.0, 96.0, 192.0, 384.0, 768.0, 1536.0,
             3072.0, 6144.0
     };
-    return ura < 0 || 15 < ura ? std::pow(2.0, 6144.0) : std::pow(2.0, ura_value[ura]);
+    return ura < 0 || 15 < ura ? std::pow(6144.0, 2.0) : std::pow(ura_value[ura], 2.0);
 }
 
 
@@ -98,10 +98,10 @@ double var_uraeph(int ura)
 double var_urassr(int ura)
 {
     double std_;
-    if (ura <= 0) return std::pow(2.0, DEFURASSR);
-    if (ura >= 63) return std::pow(2.0, 5.4665);
-    std_ = (std::pow(3.0, (ura >> 3) & 7) * (1.0 + (ura & 7) / 4.0) - 1.0) * 1e-3;
-    return std::pow(2.0, std_);
+    if (ura <= 0) return std::pow(DEFURASSR, 2.0);
+    if (ura >= 63) return std::pow(5.4665, 2.0);
+    std_ = (std::pow((ura >> 3) & 7, 2.0) * (1.0 + (ura & 7) / 4.0) - 1.0) * 1e-3;
+    return std::pow(std_, 2.0);
 }
 
 
@@ -275,7 +275,7 @@ void eph2pos(gtime_t time, const eph_t *eph, double *rs, double *dts,
     *dts = eph->f0 + eph->f1 * tk + eph->f2 * tk * tk;
 
     /* relativity correction */
-    *dts -= 2.0 * sqrt(mu * eph->A) * eph-> e* sinE / std::pow(2.0, SPEED_OF_LIGHT);
+    *dts -= 2.0 * sqrt(mu * eph->A) * eph-> e* sinE / std::pow(SPEED_OF_LIGHT, 2.0);
 
     /* position and clock error variance */
     *var = var_uraeph(eph->sva);
@@ -285,7 +285,7 @@ void eph2pos(gtime_t time, const eph_t *eph, double *rs, double *dts,
 /* glonass orbit differential equations --------------------------------------*/
 void deq(const double *x, double *xdot, const double *acc)
 {
-    double a, b, c, r2 = dot(x, x, 3), r3 = r2 * sqrt(r2), omg2 = std::pow(2.0, OMGE_GLO);
+    double a, b, c, r2 = dot(x, x, 3), r3 = r2 * sqrt(r2), omg2 = std::pow(OMGE_GLO, 2.0);
 
     if (r2 <= 0.0)
         {
@@ -293,7 +293,7 @@ void deq(const double *x, double *xdot, const double *acc)
             return;
         }
     /* ref [2] A.3.1.2 with bug fix for xdot[4],xdot[5] */
-    a = 1.5 * J2_GLO * MU_GLO * std::pow(2.0, RE_GLO) / r2 / r3; /* 3/2*J2*mu*Ae^2/r^5 */
+    a = 1.5 * J2_GLO * MU_GLO * std::pow(RE_GLO, 2.0) / r2 / r3; /* 3/2*J2*mu*Ae^2/r^5 */
     b = 5.0 * x[2] * x[2] / r2;                    /* 5*z^2/r^2 */
     c = -MU_GLO / r3 - a * (1.0 - b);                /* -mu/r^3-a(1-b) */
     xdot[0] = x[3];
@@ -376,7 +376,7 @@ void geph2pos(gtime_t time, const geph_t *geph, double *rs, double *dts,
         }
     for (i = 0; i < 3; i++) rs[i] = x[i];
 
-    *var = std::pow(2.0, ERREPH_GLO);
+    *var = std::pow(ERREPH_GLO, 2.0);
 }
 
 
@@ -858,7 +858,7 @@ void satposs(gtime_t teph, const obsd_t *obs, int n, const nav_t *nav,
                 {
                     if (!ephclk(time[i], teph, obs[i].sat, nav, dts + i * 2)) continue;
                     dts[1 + i * 2] = 0.0;
-                    *var = std::pow(2.0, STD_BRDCCLK);
+                    *var = std::pow(STD_BRDCCLK, 2.0);
                 }
         }
     for (i = 0; i < n && i < MAXOBS; i++)
diff --git a/src/algorithms/libs/rtklib/rtklib_ionex.cc b/src/algorithms/libs/rtklib/rtklib_ionex.cc
index 602ea3491..62f46f8fe 100644
--- a/src/algorithms/libs/rtklib/rtklib_ionex.cc
+++ b/src/algorithms/libs/rtklib/rtklib_ionex.cc
@@ -296,15 +296,15 @@ int readionexb(FILE *fp, const double *lats, const double *lons,
 
                     for (m = 0; m < n; m++)
                         {
-                            if (m%16 == 0 && !fgets(buff, sizeof(buff), fp)) break;
+                            if (m % 16 == 0 && !fgets(buff, sizeof(buff), fp)) break;
 
                             j = getindex(lon[0] + lon[2] * m, p->lons);
                             if ((index = dataindex(i, j, k, p->ndata)) < 0) continue;
 
-                            if ((x = str2num(buff, m%16*5, 5)) == 9999.0) continue;
+                            if ((x = str2num(buff, m % 16 * 5, 5)) == 9999.0) continue;
 
-                            if (type == 1) p->data[index] = x * pow(10.0, nexp);
-                            else p->rms[index] = (float)(x * pow(10.0, nexp));
+                            if (type == 1) p->data[index] = x * std::pow(10.0, nexp);
+                            else p->rms[index] = (float)(x * std::pow(10.0, nexp));
                         }
                 }
         }
diff --git a/src/algorithms/libs/rtklib/rtklib_pntpos.cc b/src/algorithms/libs/rtklib/rtklib_pntpos.cc
index 9ca66e52e..a8d020b69 100644
--- a/src/algorithms/libs/rtklib/rtklib_pntpos.cc
+++ b/src/algorithms/libs/rtklib/rtklib_pntpos.cc
@@ -58,9 +58,9 @@ double varerr(const prcopt_t *opt, double el, int sys)
 {
     double fact, varr;
     fact = sys == SYS_GLO ? EFACT_GLO : (sys == SYS_SBS ? EFACT_SBS : EFACT_GPS);
-    varr = std::pow(2.0, opt->err[0]) * (std::pow(2.0, opt->err[1]) + std::pow(2.0, opt->err[2]) / sin(el));
-    if (opt->ionoopt == IONOOPT_IFLC) varr *= std::pow(2.0, 3.0); /* iono-free */
-    return std::pow(2.0, fact) * varr;
+    varr = std::pow(opt->err[0], 2.0) * (std::pow(opt->err[1], 2.0) + std::pow(opt->err[2], 2.0) / sin(el));
+    if (opt->ionoopt == IONOOPT_IFLC) varr *= std::pow(2, 3.0); /* iono-free */
+    return std::pow(fact, 2.0) * varr;
 }
 
 
@@ -95,7 +95,7 @@ double prange(const obsd_t *obs, const nav_t *nav, const double *azel,
 
 
     /* L1-L2 for GPS/GLO/QZS, L1-L5 for GAL/SBS */
-    if (NFREQ >= 3 && (sys & (SYS_GAL | SYS_SBS))) j = 2;
+    if (NFREQ>=3&&(sys&(SYS_GAL|SYS_SBS))) j = 2;
 
     if (NFREQ<2 || lam[i] == 0.0 || lam[j] == 0.0)
         {
@@ -105,7 +105,7 @@ double prange(const obsd_t *obs, const nav_t *nav, const double *azel,
         }
 
     /* test snr mask */
-    if (iter > 0)
+    if (iter>0)
         {
             if (testsnr(0, i, azel[1], obs->SNR[i] * 0.25, &opt->snrmask))
                 {
@@ -122,7 +122,7 @@ double prange(const obsd_t *obs, const nav_t *nav, const double *azel,
                         }
                 }
         }
-    gamma = std::pow(2.0, lam[j]) / std::pow(2.0, lam[i]); /* f1^2/f2^2 */
+    gamma = std::pow(lam[j], 2.0) / std::pow(lam[i], 2.0); /* f1^2/f2^2 */
     P1 = obs->P[i];
     P2 = obs->P[j];
     P1_P2 = nav->cbias[obs->sat-1][0];
@@ -153,7 +153,7 @@ double prange(const obsd_t *obs, const nav_t *nav, const double *azel,
         }
     if (opt->sateph == EPHOPT_SBAS) PC -= P1_C1; /* sbas clock based C1 */
 
-    *var = std::pow(2.0, ERR_CBIAS);
+    *var = std::pow(ERR_CBIAS, 2.0);
 
     return PC;
 }
@@ -182,7 +182,7 @@ int ionocorr(gtime_t time, const nav_t *nav, int sat, const double *pos,
     if (ionoopt == IONOOPT_BRDC)
         {
             *ion = ionmodel(time, nav->ion_gps, pos, azel);
-            *var = std::pow(2.0, *ion*ERR_BRDCI);
+            *var = SQR(*ion*ERR_BRDCI);
             return 1;
         }
     /* sbas ionosphere model */
@@ -196,10 +196,10 @@ int ionocorr(gtime_t time, const nav_t *nav, int sat, const double *pos,
             return iontec(time, nav, pos, azel, 1, ion, var);
         }
     /* qzss broadcast model */
-    if (ionoopt == IONOOPT_QZS && norm(nav->ion_qzs, 8) > 0.0)
+    if (ionoopt == IONOOPT_QZS && norm(nav->ion_qzs, 8)>0.0)
         {
             *ion = ionmodel(time, nav->ion_qzs, pos, azel);
-            *var = std::pow(2.0, *ion * ERR_BRDCI);
+            *var = std::pow(*ion * ERR_BRDCI, 2.0);
             return 1;
         }
     /* lex ionosphere model */
@@ -207,7 +207,7 @@ int ionocorr(gtime_t time, const nav_t *nav, int sat, const double *pos,
     //    return lexioncorr(time, nav, pos, azel, ion, var);
     //}
     *ion = 0.0;
-    *var = ionoopt == IONOOPT_OFF ? std::pow(2.0, ERR_ION) : 0.0;
+    *var = ionoopt == IONOOPT_OFF ? std::pow(ERR_ION, 2.0) : 0.0;
     return 1;
 }
 
@@ -234,7 +234,7 @@ int tropcorr(gtime_t time, const nav_t *nav, const double *pos,
     if (tropopt == TROPOPT_SAAS || tropopt == TROPOPT_EST || tropopt == TROPOPT_ESTG)
         {
             *trp = tropmodel(time, pos, azel, REL_HUMI);
-            *var = std::pow(2.0, ERR_SAAS / (sin(azel[1]) + 0.1));
+            *var = SQR(ERR_SAAS / (sin(azel[1]) + 0.1));
             return 1;
         }
     /* sbas troposphere model */
@@ -245,7 +245,7 @@ int tropcorr(gtime_t time, const nav_t *nav, const double *pos,
         }
     /* no correction */
     *trp = 0.0;
-    *var = tropopt == TROPOPT_OFF ? std::pow(2.0, ERR_TROP) : 0.0;
+    *var = tropopt == TROPOPT_OFF ? std::pow(ERR_TROP, 2.0) : 0.0;
     return 1;
 }
 
@@ -314,7 +314,7 @@ int rescode(int iter, const obsd_t *obs, int n, const double *rs,
             /* GPS-L1 -> L1/B1 */
             if ((lam_L1 = nav->lam[obs[i].sat - 1][0]) > 0.0)
                 {
-                    dion *= pow(2.0, lam_L1 / lam_carr[0]);
+                    dion *= std::pow(lam_L1 / lam_carr[0], 2.0);
                 }
             /* tropospheric corrections */
             if (!tropcorr(obs[i].time, nav, pos, azel + i*2,
@@ -517,7 +517,7 @@ int raim_fde(const obsd_t *obs,  int n,  const double *rs,
             for (j = nvsat = 0, rms_e = 0.0; j < n - 1; j++)
                 {
                     if (!vsat_e[j]) continue;
-                    rms_e += std::pow(2.0, resp_e[j]);
+                    rms_e += std::pow(resp_e[j], 2.0);
                     nvsat++;
                 }
             if (nvsat < 5)
diff --git a/src/algorithms/libs/rtklib/rtklib_preceph.cc b/src/algorithms/libs/rtklib/rtklib_preceph.cc
index 026e3d9a3..b553c79da 100644
--- a/src/algorithms/libs/rtklib/rtklib_preceph.cc
+++ b/src/algorithms/libs/rtklib/rtklib_preceph.cc
@@ -218,7 +218,7 @@ void readsp3b(FILE *fp, char type, int *sats, int ns, double *bfact,
                                         }
                                     if ((base = bfact[j < 3 ? 0 : 1]) > 0.0 && std > 0.0)
                                         {
-                                            peph.std[sat-1][j] = (float)(pow(base, std)*(j < 3 ? 1e-3 : 1e-12));
+                                            peph.std[sat-1][j] = (float)(std::pow(base, std)*(j < 3 ? 1e-3 : 1e-12));
                                         }
                             }
                             else if (v) { /* velocity */
@@ -228,7 +228,7 @@ void readsp3b(FILE *fp, char type, int *sats, int ns, double *bfact,
                                         }
                                     if ((base = bfact[j < 3 ? 0 : 1]) > 0.0 && std > 0.0)
                                         {
-                                            peph.vst[sat-1][j] = (float)(pow(base, std)*(j < 3 ? 1e-7 : 1e-16));
+                                            peph.vst[sat-1][j] = (float)(std::pow(base, std)*(j < 3 ? 1e-7 : 1e-16));
                                         }
                             }
                         }
@@ -662,9 +662,9 @@ int pephpos(gtime_t time, int sat, const nav_t *nav, double *rs,
             std = norm(s, 3);
 
             /* extrapolation error for orbit */
-            if      (t[0   ] > 0.0) std += EXTERR_EPH * pow(2, t[0   ]) / 2.0;
-            else if (t[NMAX] < 0.0) std += EXTERR_EPH * pow(2, t[NMAX]) / 2.0;
-            *vare = pow(2, std);
+            if      (t[0   ] > 0.0) std += EXTERR_EPH * std::pow(t[0   ], 2.0) / 2.0;
+            else if (t[NMAX] < 0.0) std += EXTERR_EPH * std::pow(t[NMAX], 2.0) / 2.0;
+            *vare = std::pow(std, 2.0);
         }
     /* linear interpolation for clock */
     t[0] = timediff(time, nav->peph[index  ].time);
@@ -696,7 +696,7 @@ int pephpos(gtime_t time, int sat, const nav_t *nav, double *rs,
         {
             dts[0] = 0.0;
         }
-    if (varc) *varc = std::pow(2, std);
+    if (varc) *varc = std::pow(std, 2.0);
     return 1;
 }
 
@@ -752,7 +752,7 @@ int pephclk(gtime_t time, int sat, const nav_t *nav, double *dts,
             trace(3, "prec clock outage %s sat=%2d\n", time_str(time, 0), sat);
             return 0;
         }
-    if (varc) *varc = std::pow(2, std);
+    if (varc) *varc = std::pow(std, 2.0);
     return 1;
 }
 
@@ -795,7 +795,7 @@ void satantoff(gtime_t time, const double *rs, int sat, const nav_t *nav,
 
     if (NFREQ < 2 || lam[j] == 0.0 || lam[k] == 0.0) return;
 
-    gamma = std::pow(2, lam[k]) / std::pow(2, lam[j]);
+    gamma = std::pow(lam[k], 2.0) / std::pow(lam[j], 2.0);
     C1 = gamma / (gamma - 1.0);
     C2 = -1.0 / (gamma - 1.0);