diff --git a/src/c/funktionen.c b/src/c/funktionen.c
index b762515..6ec9a84 100644
--- a/src/c/funktionen.c
+++ b/src/c/funktionen.c
@@ -32,3 +32,13 @@ return cbrt(x);
 float absolute(float x) {
 return fabs(x);
 }
+
+// Function to calculate the logarithm (base 10) of a number
+float logarithm(float x) {
+if (x > 0) {
+return log10(x);
+} else {
+printf("Error: Invalid input for logarithm!\n");
+return 0;
+}
+}