diff --git a/squiggle_more.c b/squiggle_more.c
index c167daa..6d42eee 100644
--- a/squiggle_more.c
+++ b/squiggle_more.c
@@ -300,13 +300,13 @@ void array_print_histogram(double* xs, int n_samples, int n_bins) {
     free(bins);
 }
 
-void array_print_90_ci_histogram(double* xs, int n){
+void array_print_90_ci_histogram(double* xs, int n_samples, int n_bins){
     // Code duplicated from previous function
     // I'll consider simplifying it at some future point
     // Possible ideas:
     // - having only one function that takes any confidence interval?
     // - having a utility function that is called by both functions?
-    ci ci_90 = array_get_90_ci(xs, n);
+    ci ci_90 = array_get_90_ci(xs, n_samples);
 
     if (n_bins <= 1) {
         fprintf(stderr, "Number of bins must be greater than 1.\n");
diff --git a/squiggle_more.h b/squiggle_more.h
index 07f07a1..fa9ef43 100644
--- a/squiggle_more.h
+++ b/squiggle_more.h
@@ -12,8 +12,10 @@ typedef struct ci_t {
 } ci;
 ci array_get_ci(ci interval, double* xs, int n);
 ci array_get_90_ci(double xs[], int n);
+
 void array_print_stats(double xs[], int n);
 void array_print_histogram(double* xs, int n_samples, int n_bins);
+void array_print_90_ci_histogram(double* xs, int n, int n_bins);
 
 // Deprecated: get confidence intervals directly from samplers
 ci sampler_get_ci(ci interval, double (*sampler)(uint64_t*), int n, uint64_t* seed);