1 files changed, 17 insertions, 0 deletions
diff --git a/lib/libm/ctanl.c b/lib/libm/ctanl.c
new file mode 100644
index 00000000..a410db0e
--- /dev/null
+++ b/lib/libm/ctanl.c
@@ -0,0 +1,17 @@
+#include "__complex.h"
+
+long double complex ctanl(long double complex z)
+{
+	long double d = cosl(2.0L * creall(z)) + coshl(2.0L * cimagl(z));
+
+	if (fabsl(d) < 0.25L) {
+		d = ctansl(z);
+	}
+
+	if (d == 0.0L) {
+		return HUGE_VALL + HUGE_VALL * (long double complex)I;
+	}
+
+	return sinl(2.0L * creall(z)) / d +
+	       (sinhl(2.0L * cimagl(z)) / d) * (long double complex)I;
+}