Data was not rendering correctly due to low precision rounding in data_string. Increased precision of data strings to 10 digits. Was using data sampled at about 0.8ns and it was putting the first 10000+ points at the zero X value instead of where they should have been placed. This commit fixes the issue (at probably a small performance impact)

Author: tstrutz

source/matplot/axes_objects/bars.cpp

@@ -143,7 +143,7 @@ namespace matplot {
 
     std::string bars::data_string() {
         std::stringstream ss;
-        ss.precision(5);
+        ss.precision(10);
         ss << std::fixed;
         double m = x_minimum_difference();
         double cw = cluster_width();

source/matplot/axes_objects/box_chart.cpp

@@ -127,7 +127,7 @@ namespace matplot {
         }
         std::vector<double> unique_groups = unique(x_data_);
         std::stringstream ss;
-        ss.precision(5);
+        ss.precision(10);
         ss << std::fixed;
         // for each group
         for (size_t i = 0; i < unique_groups.size(); ++i) {

source/matplot/axes_objects/circles.cpp

@@ -45,7 +45,7 @@ namespace matplot {
 
     std::string circles::data_string() {
         std::stringstream ss;
-        ss.precision(5);
+        ss.precision(10);
         ss << std::fixed;
         for (size_t i = 0; i < x_.size(); ++i) {
             auto value_or_default = [](const std::vector<double> &v,

source/matplot/axes_objects/contours.cpp

@@ -50,7 +50,7 @@ namespace matplot {
         double contour_max_level = *max_it;
 
         std::stringstream ss;
-        ss.precision(5);
+        ss.precision(10);
         ss << std::fixed;
         if (filled_) {
             auto [lower_levels, upper_levels] = get_lowers_and_uppers();
@@ -478,7 +478,7 @@ namespace matplot {
         double zmin = *min_level_it;
 
         std::stringstream ss;
-        ss.precision(5);
+        ss.precision(10);
         ss << std::fixed;
         for (size_t i = 0; i < lines_.size(); ++i) {
             if (i != 0) {
@@ -771,7 +771,7 @@ namespace matplot {
         auto [lower_levels, upper_levels] = get_lowers_and_uppers();
 
         std::stringstream ss;
-        ss.precision(5);
+        ss.precision(10);
         ss << std::fixed;
         if (filled_) {
             // Plot the line segments

source/matplot/axes_objects/error_bar.cpp

@@ -79,7 +79,7 @@ namespace matplot {
         const bool has_x_bar = !x_negative_delta_.empty();
         const bool has_xy_bar = has_y_bar && has_x_bar;
         std::stringstream ss;
-        ss.precision(5);
+        ss.precision(10);
         ss << std::fixed;
         if (has_xy_bar) {
             for (size_t i = 0; i < y_data_.size(); ++i) {

source/matplot/axes_objects/filled_area.cpp

@@ -58,7 +58,7 @@ namespace matplot {
 
     std::string filled_area::data_string() {
         std::stringstream ss;
-        ss.precision(5);
+        ss.precision(10);
         ss << std::fixed;
 
         std::vector<double> stacked_data;

source/matplot/axes_objects/histogram.cpp

@@ -55,7 +55,7 @@ namespace matplot {
     std::string histogram::plot_string() {
         maybe_update_face_color();
         std::stringstream ss;
-        ss.precision(5);
+        ss.precision(10);
         ss << std::fixed;
         if (!is_polar()) {
             if (!stairs_only_) {
@@ -89,7 +89,7 @@ namespace matplot {
     std::string histogram::data_string() {
         make_sure_data_is_preprocessed();
         std::stringstream ss;
-        ss.precision(5);
+        ss.precision(10);
         ss << std::fixed;
         if (!is_polar()) {
             for (size_t i = 0; i < values_.size(); ++i) {

source/matplot/axes_objects/labels.cpp

@@ -98,7 +98,7 @@ namespace matplot {
             font_size_factor = (xrange_increase + yrange_increase) / 2.;
         }
         std::stringstream ss;
-        ss.precision(5);
+        ss.precision(10);
         ss << std::fixed;
         const bool custom_sizes = !sizes_.empty();
         const bool custom_colors = !colors_.empty();

source/matplot/axes_objects/line.cpp

@@ -163,7 +163,7 @@ namespace matplot {
         const bool x_is_manual = !x_data_.empty();
 
         std::stringstream ss;
-        ss.precision(5);
+        ss.precision(10);
         ss << std::fixed;
         for (const auto &style : styles_to_plot()) {
             if (visible_) {

source/matplot/axes_objects/matrix.cpp

@@ -167,7 +167,7 @@ namespace matplot {
 
         // stream matrix
         std::stringstream ss;
-        ss.precision(5);
+        ss.precision(10);
         ss << std::fixed;
         double x_width_ = x_width();
         double y_width_ = y_width();
@@ -275,7 +275,7 @@ namespace matplot {
 
     std::string matrix::image_data_string() {
         std::stringstream ss;
-        ss.precision(5);
+        ss.precision(10);
         ss << std::fixed;
         auto [h, w] = size(matrices_[0]);
         double x_width_ = x_width();