From 4dff87301316814711fdc9a0ba7d1101a3f5c97f Mon Sep 17 00:00:00 2001
From: Tyler Veness <calcmogul@gmail.com>
Date: Thu, 16 Sep 2021 20:45:24 -0700
Subject: [PATCH] [wpimath] Make LinearFilter::Factorial() constexpr (#3579)

Since BackwardFiniteDifference() gives it a compile-time constant, it
can be evaluated in a constexpr context.
---
 wpimath/src/main/native/include/frc/filter/LinearFilter.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/wpimath/src/main/native/include/frc/filter/LinearFilter.h b/wpimath/src/main/native/include/frc/filter/LinearFilter.h
index 266d149b9a..e5b6f1db3e 100644
--- a/wpimath/src/main/native/include/frc/filter/LinearFilter.h
+++ b/wpimath/src/main/native/include/frc/filter/LinearFilter.h
@@ -286,7 +286,7 @@ class LinearFilter {
    *
    * @param n Argument of which to take factorial.
    */
-  static int Factorial(int n) {
+  static constexpr int Factorial(int n) {
     if (n < 2) {
       return 1;
     } else {