1 files changed, 23 insertions, 0 deletions
diff --git a/winsup/mingw/mingwex/complex/catanh.c b/winsup/mingw/mingwex/complex/catanh.c
new file mode 100644
index 000000000..78f028014
--- /dev/null
+++ b/winsup/mingw/mingwex/complex/catanh.c
@@ -0,0 +1,23 @@
+/* catanh.c */
+/*
+   Contributed by Danny Smith
+   2003-10-20
+*/
+
+#include <math.h>
+#include <complex.h>
+
+/*  catanh (z) = -I * catan (I  * z)  */
+
+double complex catanh (double complex Z)
+{
+  double complex Tmp;
+  double complex Res;
+
+  __real__ Tmp = - __imag__ Z;
+  __imag__ Tmp =   __real__ Z;
+  Tmp = catan (Tmp);
+  __real__ Res =  __imag__ Tmp;
+  __imag__ Res = - __real__ Tmp;
+  return Res;
+}