statistics: gsl_stats_Qn_from_sorted_data

Author: mysiar

gslext.stub.php

@@ -104,4 +104,5 @@ function gsl_rstat_sd_mean(array $data): float {}
 function gsl_rstat_rms(array $data): float {}
 function gsl_rstat_skew(array $data): float {}
 function gsl_rstat_kurtosis(array $data): float {}
-function gsl_rstat_median(array $data): float {}
+function gsl_rstat_median(array $data): float {}
+function gsl_rstat_quantile_get(array $data, float $factor): float {}

gslext_arginfo.h

@@ -1,5 +1,5 @@
 /* This is a generated file, edit the .stub.php file instead.
- * Stub hash: 4d98192c53df38f52c976d4b6aefd16aed9630ac */
+ * Stub hash: d927c9345a6b29cd62bd9dbb4a3856ee6ff03cac */
 
 ZEND_BEGIN_ARG_WITH_RETURN_TYPE_INFO_EX(arginfo_GSL_log1p, 0, 1, IS_DOUBLE, 0)
 	ZEND_ARG_TYPE_INFO(0, x, IS_DOUBLE, 0)
@@ -298,6 +298,11 @@ ZEND_END_ARG_INFO()
 
 #define arginfo_gsl_rstat_median arginfo_gsl_rstat_min
 
+ZEND_BEGIN_ARG_WITH_RETURN_TYPE_INFO_EX(arginfo_gsl_rstat_quantile_get, 0, 2, IS_DOUBLE, 0)
+	ZEND_ARG_TYPE_INFO(0, data, IS_ARRAY, 0)
+	ZEND_ARG_TYPE_INFO(0, factor, IS_DOUBLE, 0)
+ZEND_END_ARG_INFO()
+
 
 ZEND_FUNCTION(GSL_log1p);
 ZEND_FUNCTION(GSL_expm1);
@@ -389,6 +394,7 @@ ZEND_FUNCTION(gsl_rstat_rms);
 ZEND_FUNCTION(gsl_rstat_skew);
 ZEND_FUNCTION(gsl_rstat_kurtosis);
 ZEND_FUNCTION(gsl_rstat_median);
+ZEND_FUNCTION(gsl_rstat_quantile_get);
 
 
 static const zend_function_entry ext_functions[] = {
@@ -482,5 +488,6 @@ static const zend_function_entry ext_functions[] = {
 	ZEND_FE(gsl_rstat_skew, arginfo_gsl_rstat_skew)
 	ZEND_FE(gsl_rstat_kurtosis, arginfo_gsl_rstat_kurtosis)
 	ZEND_FE(gsl_rstat_median, arginfo_gsl_rstat_median)
+	ZEND_FE(gsl_rstat_quantile_get, arginfo_gsl_rstat_quantile_get)
 	ZEND_FE_END
 };

inc/running_statistics.c

@@ -1,6 +1,7 @@
 // https://www.gnu.org/software/gsl/doc/html/rstat.html
 
 #include <gsl/gsl_rstat.h>
+#include <gsl/gsl_statistics_double.h>
 
 PHP_FUNCTION(gsl_rstat_min)
 {
@@ -282,4 +283,38 @@ PHP_FUNCTION(gsl_rstat_median)
     RETURN_DOUBLE(rv);
 }
 
+PHP_FUNCTION(gsl_rstat_quantile_get)
+{
+    zval *p_data, *p_factor;
+    long i, n;
+    double *data, factor, rv;
+
+    ZEND_PARSE_PARAMETERS_START(2, 2)
+            Z_PARAM_ZVAL(p_data)
+            Z_PARAM_ZVAL(p_factor)
+    ZEND_PARSE_PARAMETERS_END();
+
+    n = (long) zend_array_count(Z_ARR_P(p_data));
+    __alloc_double_array(&data, n);
+    __zval_to_double_array(p_data, data, n);
+
+    __zval_to_double(p_factor, &factor);
+
+    gsl_rstat_quantile_workspace *work = gsl_rstat_quantile_alloc(factor);
+
+    n = (long) zend_array_count(Z_ARR_P(p_data));
+
+    __alloc_double_array(&data, n);
+    __zval_to_double_array(p_data, data, n);
+
+    for (i = 0; i < n; ++i)
+        gsl_rstat_quantile_add(data[i], work);
+
+    rv = gsl_rstat_quantile_get(work);
+
+    gsl_rstat_quantile_reset(work);
+    gsl_rstat_quantile_free(work);
+
+    RETURN_DOUBLE(rv);
+}
 

tests/0008.running_statistics.phpt

@@ -37,6 +37,16 @@ var_dump(gsl_rstat_kurtosis($data));
 var_dump("gsl_rstat_median");
 var_dump(gsl_rstat_median($data));
 
+$data = [0.00645272, 0.0074002, 0.0120706, 0.0207256, 0.0227282];
+var_dump("gsl_rstat_quantile_get");
+var_dump(gsl_rstat_quantile_get($data, 0.25));
+
+var_dump("gsl_rstat_quantile_get");
+var_dump(gsl_rstat_quantile_get($data, 0.5));
+
+var_dump("gsl_rstat_quantile_get");
+var_dump(gsl_rstat_quantile_get($data, 0.75));
+
 ?>
 --EXPECT--
 string(13) "gsl_rstat_min"
@@ -59,3 +69,9 @@ string(18) "gsl_rstat_kurtosis"
 float(-1.2217029020861698)
 string(16) "gsl_rstat_median"
 float(17.2)
+string(22) "gsl_rstat_quantile_get"
+float(0.0074002)
+string(22) "gsl_rstat_quantile_get"
+float(0.0120706)
+string(22) "gsl_rstat_quantile_get"
+float(0.0207256)