Apply clang-tidy11 to statistics

diff --git a/src/gromacs/gmxana/gmx_analyze.cpp b/src/gromacs/gmxana/gmx_analyze.cpp
index b47090c5012062d8de4ea68c85a984eb668d71a4..baaf2e968ee8620ce99bbfed6ddd8df35d007ad8 100644 (file)
--- a/src/gromacs/gmxana/gmx_analyze.cpp
+++ b/src/gromacs/gmxana/gmx_analyze.cpp
@@ -164,8 +164,8 @@ static void plot_coscont(const char* ccfile, int n, int nset, real** val, const
 
 static void regression_analysis(int n, gmx_bool bXYdy, real* x, int nset, real** val)
 {
-    real S, chi2, a, b, da, db, r = 0;
-    int  ok;
+    real             S, chi2, a, b, da, db, r = 0;
+    StatisticsStatus ok;
 
     if (bXYdy || (nset == 1))
     {
@@ -175,16 +175,17 @@ static void regression_analysis(int n, gmx_bool bXYdy, real* x, int nset, real**
         printf("(use option -xydy).\n\n");
         if (bXYdy)
         {
-            if ((ok = lsq_y_ax_b_error(n, x, val[0], val[1], &a, &b, &da, &db, &r, &S)) != estatsOK)
+            if ((ok = lsq_y_ax_b_error(n, x, val[0], val[1], &a, &b, &da, &db, &r, &S))
+                != StatisticsStatus::Ok)
             {
-                gmx_fatal(FARGS, "Error fitting the data: %s", gmx_stats_message(ok));
+                gmx_stats_message(ok);
             }
         }
         else
         {
-            if ((ok = lsq_y_ax_b(n, x, val[0], &a, &b, &r, &S)) != estatsOK)
+            if ((ok = lsq_y_ax_b(n, x, val[0], &a, &b, &r, &S)) != StatisticsStatus::Ok)
             {
-                gmx_fatal(FARGS, "Error fitting the data: %s", gmx_stats_message(ok));
+                gmx_stats_message(ok);
             }
         }
         chi2 = gmx::square((n - 2) * S);

diff --git a/src/gromacs/statistics/statistics.cpp b/src/gromacs/statistics/statistics.cpp
index 2e30ce8d69845bf72f7b3fe193903fe0313a4d1b..596e8fc021a09e4d6afb4724571543ed2af9e3f0 100644 (file)
--- a/src/gromacs/statistics/statistics.cpp
+++ b/src/gromacs/statistics/statistics.cpp
@@ -4,7 +4,7 @@
  * Copyright (c) 1991-2000, University of Groningen, The Netherlands.
  * Copyright (c) 2001-2004, The GROMACS development team.
  * Copyright (c) 2012,2014,2015,2017,2018 by the GROMACS development team.
- * Copyright (c) 2019,2020, by the GROMACS development team, led by
+ * Copyright (c) 2019,2020,2021, by the GROMACS development team, led by
  * Mark Abraham, David van der Spoel, Berk Hess, and Erik Lindahl,
  * and including many others, as listed in the AUTHORS file in the
  * top-level source directory and at http://www.gromacs.org.
@@ -43,6 +43,7 @@
 
 #include "gromacs/math/functions.h"
 #include "gromacs/math/vec.h"
+#include "gromacs/utility/enumerationhelpers.h"
 #include "gromacs/utility/fatalerror.h"
 #include "gromacs/utility/real.h"
 #include "gromacs/utility/smalloc.h"
@@ -70,13 +71,13 @@ gmx_stats_t gmx_stats_init()
     return static_cast<gmx_stats_t>(stats);
 }
 
-int gmx_stats_get_npoints(gmx_stats_t gstats, int* N)
+StatisticsStatus gmx_stats_get_npoints(gmx_stats_t gstats, int* N)
 {
     gmx_stats* stats = static_cast<gmx_stats*>(gstats);
 
     *N = stats->np;
 
-    return estatsOK;
+    return StatisticsStatus::Ok;
 }
 
 void gmx_stats_free(gmx_stats_t gstats)
@@ -90,7 +91,7 @@ void gmx_stats_free(gmx_stats_t gstats)
     sfree(stats);
 }
 
-int gmx_stats_add_point(gmx_stats_t gstats, double x, double y, double dx, double dy)
+StatisticsStatus gmx_stats_add_point(gmx_stats_t gstats, double x, double y, double dx, double dy)
 {
     gmx_stats* stats = gstats;
 
@@ -123,16 +124,17 @@ int gmx_stats_add_point(gmx_stats_t gstats, double x, double y, double dx, doubl
     stats->np++;
     stats->computed = 0;
 
-    return estatsOK;
+    return StatisticsStatus::Ok;
 }
 
-int gmx_stats_get_point(gmx_stats_t gstats, real* x, real* y, real* dx, real* dy, real level)
+StatisticsStatus gmx_stats_get_point(gmx_stats_t gstats, real* x, real* y, real* dx, real* dy, real level)
 {
-    gmx_stats* stats = gstats;
-    int        ok, outlier;
-    real       rmsd, r;
+    gmx_stats*       stats = gstats;
+    StatisticsStatus ok;
+    int              outlier;
+    real             rmsd, r;
 
-    if ((ok = gmx_stats_get_rmsd(gstats, &rmsd)) != estatsOK)
+    if ((ok = gmx_stats_get_rmsd(gstats, &rmsd)) != StatisticsStatus::Ok)
     {
         return ok;
     }
@@ -164,31 +166,31 @@ int gmx_stats_get_point(gmx_stats_t gstats, real* x, real* y, real* dx, real* dy
 
         if (outlier)
         {
-            return estatsOK;
+            return StatisticsStatus::Ok;
         }
     }
 
     stats->np_c = 0;
 
-    return estatsNO_POINTS;
+    return StatisticsStatus::NoPoints;
 }
 
-int gmx_stats_add_points(gmx_stats_t gstats, int n, real* x, real* y, real* dx, real* dy)
+StatisticsStatus gmx_stats_add_points(gmx_stats_t gstats, int n, real* x, real* y, real* dx, real* dy)
 {
     for (int i = 0; (i < n); i++)
     {
-        int ok;
+        StatisticsStatus ok;
         if ((ok = gmx_stats_add_point(
                      gstats, x[i], y[i], (nullptr != dx) ? dx[i] : 0, (nullptr != dy) ? dy[i] : 0))
-            != estatsOK)
+            != StatisticsStatus::Ok)
         {
             return ok;
         }
     }
-    return estatsOK;
+    return StatisticsStatus::Ok;
 }
 
-static int gmx_stats_compute(gmx_stats* stats, int weight)
+static StatisticsStatus gmx_stats_compute(gmx_stats* stats, int weight)
 {
     double yy, yx, xx, sx, sy, dy, chi2, chi2aa, d2;
     double ssxx, ssyy, ssxy;
@@ -200,7 +202,7 @@ static int gmx_stats_compute(gmx_stats* stats, int weight)
     {
         if (N < 1)
         {
-            return estatsNO_POINTS;
+            return StatisticsStatus::NoPoints;
         }
 
         xx = xx_nw = 0;
@@ -314,15 +316,16 @@ static int gmx_stats_compute(gmx_stats* stats, int weight)
         stats->computed = 1;
     }
 
-    return estatsOK;
+    return StatisticsStatus::Ok;
 }
 
-int gmx_stats_get_ab(gmx_stats_t gstats, int weight, real* a, real* b, real* da, real* db, real* chi2, real* Rfit)
+StatisticsStatus
+gmx_stats_get_ab(gmx_stats_t gstats, int weight, real* a, real* b, real* da, real* db, real* chi2, real* Rfit)
 {
-    gmx_stats* stats = gstats;
-    int        ok;
+    gmx_stats*       stats = gstats;
+    StatisticsStatus ok;
 
-    if ((ok = gmx_stats_compute(stats, weight)) != estatsOK)
+    if ((ok = gmx_stats_compute(stats, weight)) != StatisticsStatus::Ok)
     {
         return ok;
     }
@@ -351,15 +354,15 @@ int gmx_stats_get_ab(gmx_stats_t gstats, int weight, real* a, real* b, real* da,
         *Rfit = stats->Rfit;
     }
 
-    return estatsOK;
+    return StatisticsStatus::Ok;
 }
 
-int gmx_stats_get_a(gmx_stats_t gstats, int weight, real* a, real* da, real* chi2, real* Rfit)
+StatisticsStatus gmx_stats_get_a(gmx_stats_t gstats, int weight, real* a, real* da, real* chi2, real* Rfit)
 {
-    gmx_stats* stats = gstats;
-    int        ok;
+    gmx_stats*       stats = gstats;
+    StatisticsStatus ok;
 
-    if ((ok = gmx_stats_compute(stats, weight)) != estatsOK)
+    if ((ok = gmx_stats_compute(stats, weight)) != StatisticsStatus::Ok)
     {
         return ok;
     }
@@ -380,30 +383,30 @@ int gmx_stats_get_a(gmx_stats_t gstats, int weight, real* a, real* da, real* chi
         *Rfit = stats->Rfitaa;
     }
 
-    return estatsOK;
+    return StatisticsStatus::Ok;
 }
 
-int gmx_stats_get_average(gmx_stats_t gstats, real* aver)
+StatisticsStatus gmx_stats_get_average(gmx_stats_t gstats, real* aver)
 {
-    gmx_stats* stats = gstats;
-    int        ok;
+    gmx_stats*       stats = gstats;
+    StatisticsStatus ok;
 
-    if ((ok = gmx_stats_compute(stats, elsqWEIGHT_NONE)) != estatsOK)
+    if ((ok = gmx_stats_compute(stats, elsqWEIGHT_NONE)) != StatisticsStatus::Ok)
     {
         return ok;
     }
 
     *aver = stats->aver;
 
-    return estatsOK;
+    return StatisticsStatus::Ok;
 }
 
-int gmx_stats_get_ase(gmx_stats_t gstats, real* aver, real* sigma, real* error)
+StatisticsStatus gmx_stats_get_ase(gmx_stats_t gstats, real* aver, real* sigma, real* error)
 {
-    gmx_stats* stats = gstats;
-    int        ok;
+    gmx_stats*       stats = gstats;
+    StatisticsStatus ok;
 
-    if ((ok = gmx_stats_compute(stats, elsqWEIGHT_NONE)) != estatsOK)
+    if ((ok = gmx_stats_compute(stats, elsqWEIGHT_NONE)) != StatisticsStatus::Ok)
     {
         return ok;
     }
@@ -421,70 +424,70 @@ int gmx_stats_get_ase(gmx_stats_t gstats, real* aver, real* sigma, real* error)
         *error = stats->error;
     }
 
-    return estatsOK;
+    return StatisticsStatus::Ok;
 }
 
-int gmx_stats_get_sigma(gmx_stats_t gstats, real* sigma)
+StatisticsStatus gmx_stats_get_sigma(gmx_stats_t gstats, real* sigma)
 {
-    gmx_stats* stats = gstats;
-    int        ok;
+    gmx_stats*       stats = gstats;
+    StatisticsStatus ok;
 
-    if ((ok = gmx_stats_compute(stats, elsqWEIGHT_NONE)) != estatsOK)
+    if ((ok = gmx_stats_compute(stats, elsqWEIGHT_NONE)) != StatisticsStatus::Ok)
     {
         return ok;
     }
 
     *sigma = stats->sigma_aver;
 
-    return estatsOK;
+    return StatisticsStatus::Ok;
 }
 
-int gmx_stats_get_error(gmx_stats_t gstats, real* error)
+StatisticsStatus gmx_stats_get_error(gmx_stats_t gstats, real* error)
 {
-    gmx_stats* stats = gstats;
-    int        ok;
+    gmx_stats*       stats = gstats;
+    StatisticsStatus ok;
 
-    if ((ok = gmx_stats_compute(stats, elsqWEIGHT_NONE)) != estatsOK)
+    if ((ok = gmx_stats_compute(stats, elsqWEIGHT_NONE)) != StatisticsStatus::Ok)
     {
         return ok;
     }
 
     *error = stats->error;
 
-    return estatsOK;
+    return StatisticsStatus::Ok;
 }
 
-int gmx_stats_get_corr_coeff(gmx_stats_t gstats, real* R)
+StatisticsStatus gmx_stats_get_corr_coeff(gmx_stats_t gstats, real* R)
 {
-    gmx_stats* stats = gstats;
-    int        ok;
+    gmx_stats*       stats = gstats;
+    StatisticsStatus ok;
 
-    if ((ok = gmx_stats_compute(stats, elsqWEIGHT_NONE)) != estatsOK)
+    if ((ok = gmx_stats_compute(stats, elsqWEIGHT_NONE)) != StatisticsStatus::Ok)
     {
         return ok;
     }
 
     *R = stats->Rdata;
 
-    return estatsOK;
+    return StatisticsStatus::Ok;
 }
 
-int gmx_stats_get_rmsd(gmx_stats_t gstats, real* rmsd)
+StatisticsStatus gmx_stats_get_rmsd(gmx_stats_t gstats, real* rmsd)
 {
-    gmx_stats* stats = gstats;
-    int        ok;
+    gmx_stats*       stats = gstats;
+    StatisticsStatus ok;
 
-    if ((ok = gmx_stats_compute(stats, elsqWEIGHT_NONE)) != estatsOK)
+    if ((ok = gmx_stats_compute(stats, elsqWEIGHT_NONE)) != StatisticsStatus::Ok)
     {
         return ok;
     }
 
     *rmsd = stats->rmsd;
 
-    return estatsOK;
+    return StatisticsStatus::Ok;
 }
 
-int gmx_stats_dump_xy(gmx_stats_t gstats, FILE* fp)
+StatisticsStatus gmx_stats_dump_xy(gmx_stats_t gstats, FILE* fp)
 {
     gmx_stats* stats = gstats;
 
@@ -493,18 +496,19 @@ int gmx_stats_dump_xy(gmx_stats_t gstats, FILE* fp)
         fprintf(fp, "%12g  %12g  %12g  %12g\n", stats->x[i], stats->y[i], stats->dx[i], stats->dy[i]);
     }
 
-    return estatsOK;
+    return StatisticsStatus::Ok;
 }
 
-int gmx_stats_remove_outliers(gmx_stats_t gstats, double level)
+StatisticsStatus gmx_stats_remove_outliers(gmx_stats_t gstats, double level)
 {
-    gmx_stats* stats = gstats;
-    int        iter = 1, done = 0, ok;
-    real       rmsd, r;
+    gmx_stats*       stats = gstats;
+    int              iter = 1, done = 0;
+    StatisticsStatus ok;
+    real             rmsd, r;
 
     while ((stats->np >= 10) && !done)
     {
-        if ((ok = gmx_stats_get_rmsd(gstats, &rmsd)) != estatsOK)
+        if ((ok = gmx_stats_get_rmsd(gstats, &rmsd)) != StatisticsStatus::Ok)
         {
             return ok;
         }
@@ -538,10 +542,16 @@ int gmx_stats_remove_outliers(gmx_stats_t gstats, double level)
         iter++;
     }
 
-    return estatsOK;
+    return StatisticsStatus::Ok;
 }
 
-int gmx_stats_make_histogram(gmx_stats_t gstats, real binwidth, int* nb, int ehisto, int normalized, real** x, real** y)
+StatisticsStatus gmx_stats_make_histogram(gmx_stats_t gstats,
+                                          real        binwidth,
+                                          int*        nb,
+                                          int         ehisto,
+                                          int         normalized,
+                                          real**      x,
+                                          real**      y)
 {
     gmx_stats* stats = gstats;
     int        index = 0, nbins = *nb, *nindex;
@@ -549,11 +559,11 @@ int gmx_stats_make_histogram(gmx_stats_t gstats, real binwidth, int* nb, int ehi
 
     if (((binwidth <= 0) && (nbins <= 0)) || ((binwidth > 0) && (nbins > 0)))
     {
-        return estatsINVALID_INPUT;
+        return StatisticsStatus::InvalidInput;
     }
     if (stats->np <= 2)
     {
-        return estatsNO_POINTS;
+        return StatisticsStatus::NoPoints;
     }
     minx = maxx = stats->x[0];
     miny = maxy = stats->y[0];
@@ -576,7 +586,7 @@ int gmx_stats_make_histogram(gmx_stats_t gstats, real binwidth, int* nb, int ehi
     }
     else
     {
-        return estatsINVALID_INPUT;
+        return StatisticsStatus::InvalidInput;
     }
 
     if (binwidth == 0)
@@ -638,44 +648,42 @@ int gmx_stats_make_histogram(gmx_stats_t gstats, real binwidth, int* nb, int ehi
 
     sfree(nindex);
 
-    return estatsOK;
+    return StatisticsStatus::Ok;
 }
 
-static const char* stats_error[estatsNR] = { "All well in STATS land", "No points",
-                                             "Not enough memory",      "Invalid histogram input",
-                                             "Unknown error",          "Not implemented yet" };
+static const char* enumValueToString(StatisticsStatus enumValue)
+{
+    constexpr gmx::EnumerationArray<StatisticsStatus, const char*> statisticsStatusNames = {
+        "All well in STATS land",  "No points",     "Not enough memory",
+        "Invalid histogram input", "Unknown error", "Not implemented yet"
+    };
+    return statisticsStatusNames[enumValue];
+}
 
-const char* gmx_stats_message(int estats)
+void gmx_stats_message([[maybe_unused]] StatisticsStatus estats)
 {
-    if ((estats >= 0) && (estats < estatsNR))
-    {
-        return stats_error[estats];
-    }
-    else
-    {
-        return stats_error[estatsERROR];
-    }
+    GMX_ASSERT(estats == StatisticsStatus::Ok, enumValueToString(estats));
 }
 
 /* Old convenience functions, should be merged with the core
    statistics above. */
-int lsq_y_ax(int n, real x[], real y[], real* a)
+StatisticsStatus lsq_y_ax(int n, real x[], real y[], real* a)
 {
     gmx_stats_t lsq = gmx_stats_init();
-    int         ok;
     real        da, chi2, Rfit;
 
     gmx_stats_add_points(lsq, n, x, y, nullptr, nullptr);
-    ok = gmx_stats_get_a(lsq, elsqWEIGHT_NONE, a, &da, &chi2, &Rfit);
+    StatisticsStatus ok = gmx_stats_get_a(lsq, elsqWEIGHT_NONE, a, &da, &chi2, &Rfit);
     gmx_stats_free(lsq);
 
     return ok;
 }
 
-static int low_lsq_y_ax_b(int n, const real* xr, const double* xd, real yr[], real* a, real* b, real* r, real* chi2)
+static StatisticsStatus
+low_lsq_y_ax_b(int n, const real* xr, const double* xd, real yr[], real* a, real* b, real* r, real* chi2)
 {
-    gmx_stats_t lsq = gmx_stats_init();
-    int         ok;
+    gmx_stats_t      lsq = gmx_stats_init();
+    StatisticsStatus ok;
 
     for (int i = 0; (i < n); i++)
     {
@@ -694,7 +702,7 @@ static int low_lsq_y_ax_b(int n, const real* xr, const double* xd, real yr[], re
             gmx_incons("Either xd or xr has to be non-NULL in low_lsq_y_ax_b()");
         }
 
-        if ((ok = gmx_stats_add_point(lsq, pt, yr[i], 0, 0)) != estatsOK)
+        if ((ok = gmx_stats_add_point(lsq, pt, yr[i], 0, 0)) != StatisticsStatus::Ok)
         {
             gmx_stats_free(lsq);
             return ok;
@@ -706,25 +714,26 @@ static int low_lsq_y_ax_b(int n, const real* xr, const double* xd, real yr[], re
     return ok;
 }
 
-int lsq_y_ax_b(int n, real x[], real y[], real* a, real* b, real* r, real* chi2)
+StatisticsStatus lsq_y_ax_b(int n, real x[], real y[], real* a, real* b, real* r, real* chi2)
 {
     return low_lsq_y_ax_b(n, x, nullptr, y, a, b, r, chi2);
 }
 
-int lsq_y_ax_b_xdouble(int n, double x[], real y[], real* a, real* b, real* r, real* chi2)
+StatisticsStatus lsq_y_ax_b_xdouble(int n, double x[], real y[], real* a, real* b, real* r, real* chi2)
 {
     return low_lsq_y_ax_b(n, nullptr, x, y, a, b, r, chi2);
 }
 
-int lsq_y_ax_b_error(int n, real x[], real y[], real dy[], real* a, real* b, real* da, real* db, real* r, real* chi2)
+StatisticsStatus
+lsq_y_ax_b_error(int n, real x[], real y[], real dy[], real* a, real* b, real* da, real* db, real* r, real* chi2)
 {
-    gmx_stats_t lsq = gmx_stats_init();
-    int         ok;
+    gmx_stats_t      lsq = gmx_stats_init();
+    StatisticsStatus ok;
 
     for (int i = 0; (i < n); i++)
     {
         ok = gmx_stats_add_point(lsq, x[i], y[i], 0, dy[i]);
-        if (ok != estatsOK)
+        if (ok != StatisticsStatus::Ok)
         {
             gmx_stats_free(lsq);
             return ok;

diff --git a/src/gromacs/statistics/statistics.h b/src/gromacs/statistics/statistics.h
index 818bdf317ae14ca2358b479c4d0f416d8643e3ef..0d3378a63edf1dadfeeebf2dc10d1f0308d68e69 100644 (file)
--- a/src/gromacs/statistics/statistics.h
+++ b/src/gromacs/statistics/statistics.h
@@ -3,7 +3,7 @@
  *
  * Copyright (c) 1991-2000, University of Groningen, The Netherlands.
  * Copyright (c) 2001-2008, The GROMACS development team.
- * Copyright (c) 2010,2014,2015,2019, by the GROMACS development team, led by
+ * Copyright (c) 2010,2014,2015,2019,2021, by the GROMACS development team, led by
  * Mark Abraham, David van der Spoel, Berk Hess, and Erik Lindahl,
  * and including many others, as listed in the AUTHORS file in the
  * top-level source directory and at http://www.gromacs.org.
@@ -52,15 +52,15 @@
 typedef struct gmx_stats* gmx_stats_t;
 
 //! Error codes returned by the routines
-enum
+enum class StatisticsStatus : int
 {
-    estatsOK,
-    estatsNO_POINTS,
-    estatsNO_MEMORY,
-    estatsERROR,
-    estatsINVALID_INPUT,
-    estatsNOT_IMPLEMENTED,
-    estatsNR
+    Ok,
+    NoPoints,
+    NoMemory,
+    Error,
+    InvalidInput,
+    NotImplemented,
+    Count
 };
 
 //! Enum for statistical weights
@@ -100,7 +100,7 @@ void gmx_stats_free(gmx_stats_t stats);
  * \param[in] level The sigma level
  * \return error code
  */
-int gmx_stats_remove_outliers(gmx_stats_t stats, double level);
+StatisticsStatus gmx_stats_remove_outliers(gmx_stats_t stats, double level);
 
 /*! \brief
  * Add a point to the data set
@@ -111,7 +111,7 @@ int gmx_stats_remove_outliers(gmx_stats_t stats, double level);
  * \param[in] dy  The error in the y value
  * \return error code
  */
-int gmx_stats_add_point(gmx_stats_t stats, double x, double y, double dx, double dy);
+StatisticsStatus gmx_stats_add_point(gmx_stats_t stats, double x, double y, double dx, double dy);
 
 /*! \brief
  * Add a series of datapoints at once. The arrays dx and dy may
@@ -125,7 +125,7 @@ int gmx_stats_add_point(gmx_stats_t stats, double x, double y, double dx, double
  * \param[in] dy  The error in the y value
  * \return error code
  */
-int gmx_stats_add_points(gmx_stats_t stats, int n, real* x, real* y, real* dx, real* dy);
+StatisticsStatus gmx_stats_add_points(gmx_stats_t stats, int n, real* x, real* y, real* dx, real* dy);
 
 /*! \brief
  * Delivers data points from the statistics.
@@ -146,7 +146,7 @@ int gmx_stats_add_points(gmx_stats_t stats, int n, real* x, real* y, real* dx, r
  * \param[in]  level sigma level (see above)
  * \return error code
  */
-int gmx_stats_get_point(gmx_stats_t stats, real* x, real* y, real* dx, real* dy, real level);
+StatisticsStatus gmx_stats_get_point(gmx_stats_t stats, real* x, real* y, real* dx, real* dy, real level);
 
 /*! \brief
  * Fit the data to y = ax + b, possibly weighted, if uncertainties
@@ -161,7 +161,8 @@ int gmx_stats_get_point(gmx_stats_t stats, real* x, real* y, real* dx, real* dy,
  * \param[out] Rfit correlation coefficient
  * \return error code
  */
-int gmx_stats_get_ab(gmx_stats_t stats, int weight, real* a, real* b, real* da, real* db, real* chi2, real* Rfit);
+StatisticsStatus
+gmx_stats_get_ab(gmx_stats_t stats, int weight, real* a, real* b, real* da, real* db, real* chi2, real* Rfit);
 
 /*! \brief
  * Fit the data to y = ax, possibly weighted, if uncertainties have
@@ -174,7 +175,7 @@ int gmx_stats_get_ab(gmx_stats_t stats, int weight, real* a, real* b, real* da,
  * \param[out] Rfit correlation coefficient
  * \return error code
  */
-int gmx_stats_get_a(gmx_stats_t stats, int weight, real* a, real* da, real* chi2, real* Rfit);
+StatisticsStatus gmx_stats_get_a(gmx_stats_t stats, int weight, real* a, real* da, real* chi2, real* Rfit);
 
 /*! \brief
  * Get the correlation coefficient.
@@ -182,7 +183,7 @@ int gmx_stats_get_a(gmx_stats_t stats, int weight, real* a, real* da, real* chi2
  * \param[out] R the correlation coefficient between the data (x and y) as input to the structure.
  * \return error code
  */
-int gmx_stats_get_corr_coeff(gmx_stats_t stats, real* R);
+StatisticsStatus gmx_stats_get_corr_coeff(gmx_stats_t stats, real* R);
 
 /*! \brief
  * Get the root mean square deviation.
@@ -190,7 +191,7 @@ int gmx_stats_get_corr_coeff(gmx_stats_t stats, real* R);
  * \param[out] rmsd  the root mean square deviation between x and y values.
  * \return error code
  */
-int gmx_stats_get_rmsd(gmx_stats_t stats, real* rmsd);
+StatisticsStatus gmx_stats_get_rmsd(gmx_stats_t stats, real* rmsd);
 
 /*! \brief
  * Get the number of points.
@@ -198,7 +199,7 @@ int gmx_stats_get_rmsd(gmx_stats_t stats, real* rmsd);
  * \param[out] N     number of data points
  * \return error code
  */
-int gmx_stats_get_npoints(gmx_stats_t stats, int* N);
+StatisticsStatus gmx_stats_get_npoints(gmx_stats_t stats, int* N);
 
 /*! \brief
  * Computes and returns the average value.
@@ -206,7 +207,7 @@ int gmx_stats_get_npoints(gmx_stats_t stats, int* N);
  * \param[out] aver  Average value
  * \return error code
  */
-int gmx_stats_get_average(gmx_stats_t stats, real* aver);
+StatisticsStatus gmx_stats_get_average(gmx_stats_t stats, real* aver);
 
 /*! \brief
  * Computes and returns the standard deviation.
@@ -214,7 +215,7 @@ int gmx_stats_get_average(gmx_stats_t stats, real* aver);
  * \param[out] sigma  Standard deviation
  * \return error code
  */
-int gmx_stats_get_sigma(gmx_stats_t stats, real* sigma);
+StatisticsStatus gmx_stats_get_sigma(gmx_stats_t stats, real* sigma);
 
 /*! \brief
  * Computes and returns the standard error.
@@ -222,7 +223,7 @@ int gmx_stats_get_sigma(gmx_stats_t stats, real* sigma);
  * \param[out] error Standard error
  * \return error code
  */
-int gmx_stats_get_error(gmx_stats_t stats, real* error);
+StatisticsStatus gmx_stats_get_error(gmx_stats_t stats, real* error);
 
 /*! \brief
  * Pointers may be null, in which case no assignment will be done.
@@ -232,7 +233,7 @@ int gmx_stats_get_error(gmx_stats_t stats, real* error);
  * \param[out] error Standard error
  * \return error code
  */
-int gmx_stats_get_ase(gmx_stats_t stats, real* aver, real* sigma, real* error);
+StatisticsStatus gmx_stats_get_ase(gmx_stats_t stats, real* aver, real* sigma, real* error);
 
 /*! \brief
  * Dump the x, y, dx, dy data to a text file
@@ -240,7 +241,7 @@ int gmx_stats_get_ase(gmx_stats_t stats, real* aver, real* sigma, real* error);
  * \param[in] fp  File pointer
  * \return error code
  */
-int gmx_stats_dump_xy(gmx_stats_t stats, FILE* fp);
+StatisticsStatus gmx_stats_dump_xy(gmx_stats_t stats, FILE* fp);
 
 /*! \brief
  * Make a histogram of the data present.
@@ -263,19 +264,19 @@ int gmx_stats_dump_xy(gmx_stats_t stats, FILE* fp);
  * \param[out] y see above
  * \return error code
  */
-int gmx_stats_make_histogram(gmx_stats_t stats,
-                             real        binwidth,
-                             int*        nbins,
-                             int         ehisto,
-                             int         normalized,
-                             real**      x,
-                             real**      y);
+StatisticsStatus gmx_stats_make_histogram(gmx_stats_t stats,
+                                          real        binwidth,
+                                          int*        nbins,
+                                          int         ehisto,
+                                          int         normalized,
+                                          real**      x,
+                                          real**      y);
 
-/*! \brief
- * Return message belonging to error code
+/*! \brief Assert that statistics are OK
+ *
  * \param[in] estats error code
  */
-const char* gmx_stats_message(int estats);
+void gmx_stats_message([[maybe_unused]] StatisticsStatus estats);
 
 /****************************************************
  * Some statistics utilities for convenience: useful when a complete data
@@ -290,7 +291,7 @@ const char* gmx_stats_message(int estats);
  * \param[out] a slope
  * \return error code
  */
-int lsq_y_ax(int n, real x[], real y[], real* a);
+StatisticsStatus lsq_y_ax(int n, real x[], real y[], real* a);
 
 /*! \brief
  * Fit a straight line y=ax+b thru the n data points x, y.
@@ -303,11 +304,11 @@ int lsq_y_ax(int n, real x[], real y[], real* a);
  * \param[out] chi2 quality of fit
  * \return error code
  */
-int lsq_y_ax_b(int n, real x[], real y[], real* a, real* b, real* r, real* chi2);
+StatisticsStatus lsq_y_ax_b(int n, real x[], real y[], real* a, real* b, real* r, real* chi2);
 
 /*! \copydoc lsq_y_ax_b
  */
-int lsq_y_ax_b_xdouble(int n, double x[], real y[], real* a, real* b, real* r, real* chi2);
+StatisticsStatus lsq_y_ax_b_xdouble(int n, double x[], real y[], real* a, real* b, real* r, real* chi2);
 
 /*! \brief
  * Fit a straight line y=ax+b thru the n data points x, y.
@@ -323,6 +324,7 @@ int lsq_y_ax_b_xdouble(int n, double x[], real y[], real* a, real* b, real* r, r
  * \param[out] chi2 quality of fit
  * \return error code
  */
-int lsq_y_ax_b_error(int n, real x[], real y[], real dy[], real* a, real* b, real* da, real* db, real* r, real* chi2);
+StatisticsStatus
+lsq_y_ax_b_error(int n, real x[], real y[], real dy[], real* a, real* b, real* da, real* db, real* r, real* chi2);
 
 #endif