diff --git a/lib/node_modules/@stdlib/math/base/special/gammaincinv/README.md b/lib/node_modules/@stdlib/math/base/special/gammaincinv/README.md
index 7426de70ddd1..64c2dc236129 100644
--- a/lib/node_modules/@stdlib/math/base/special/gammaincinv/README.md
+++ b/lib/node_modules/@stdlib/math/base/special/gammaincinv/README.md
@@ -2,7 +2,7 @@
@license Apache-2.0
-Copyright (c) 2018 The Stdlib Authors.
+Copyright (c) 2026 The Stdlib Authors.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
@@ -70,7 +70,7 @@ Again, for given `p` and `a` the function returns the `x` which satisfies `p = Q
var gammaincinv = require( '@stdlib/math/base/special/gammaincinv' );
```
-#### gammaincinv( p, s\[, upper ] )
+#### gammaincinv( p, a\[, upper ] )
Inverts the regularized incomplete gamma function. Contrary to the more commonly used definition, in this implementation the first argument is the probability `p` and the second argument is the scale factor `a`. By default, the function inverts the _lower_ regularized incomplete gamma function, `P(x,a)`. To invert the _upper_ function instead, i.e. `Q(x,a)`, set the `upper` argument to `true`.
@@ -136,6 +136,92 @@ logEachMap( 'p: %0.4f, \t a: %0.4f, \t P^(-1)(p, a): %0.4f', p, a, gammaincinv )
+
+
+
+## C API
+
+
+
+
+
+### Usage
+
+```c
+#include "stdlib/math/base/special/gammaincinv.h"
+```
+
+#### stdlib_base_gammaincinv( p, a, upper )
+
+Inverts the regularized incomplete gamma function.
+
+```c
+double y = stdlib_base_gammaincinv( 0.5, 2.0, false );
+// returns ~1.678
+
+y = stdlib_base_gammaincinv( 0.1, 10.0, false );
+// returns ~6.221
+
+y = stdlib_base_gammaincinv( 0.75, 3.0, true );
+// returns ~1.727
+```
+
+The function accepts the following arguments:
+
+- `p`: `[in] double` input probability.
+- `a`: `[in] double` scale parameter.
+- `upper`: `[in] bool` boolean indicating if the function should invert the upper tail of the incomplete gamma function.
+
+```c
+double stdlib_base_gammaincinv( const double p, const double a, const bool upper );
+```
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+### Examples
+
+```c
+#include "stdlib/math/base/special/gammaincinv.h"
+#include
+#include
+
+int main( void ) {
+ double p;
+ double a;
+ double y;
+ int i;
+
+ for ( i = 0; i < 100; i++ ) {
+ p = (double)rand() / (double)RAND_MAX;
+ a = ( ( (double)rand() / (double)RAND_MAX ) * 20.0 );
+ y = stdlib_base_gammaincinv( p, a, false );
+ printf( "p: %lf, a: %lf, y: %lf\n", p, a, y );
+ }
+}
+```
+
+
+
+
+
+
+
+
+