circuit: fix log2Ceil

zkemail · May 20, 2024 · 9917437 · 9917437
1 parent 27ccace
commit 9917437
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Showing 2 changed files with 5 additions and 5 deletions.
diff --git a/packages/circuits/README.md b/packages/circuits/README.md
@@ -278,14 +278,14 @@ Constants: Defines a set of constants used across various circom circuits for st
 
 <details>
 <summary>
-log2Ceil: Calculates the ceiling of the base 2 logarithm of a given number.
+log2Ceil: Calculate log2 of a number and round it up
 </summary>
 
 - **[Source](utils/functions.circom#L2-L10)**
 - **Inputs**:
-  - `a`: The input number for which the base 2 logarithm ceiling is to be calculated.
+  - `a`: The input number for which the `ceil(log2())` needs to be calculated.
 - **Outputs**:
-  - Returns the smallest integer greater than or equal to the base 2 logarithm of the input number.
+  - Returns `ceil(log2())` of the input number.
 </details>
 
 

diff --git a/packages/circuits/utils/functions.circom b/packages/circuits/utils/functions.circom
@@ -1,11 +1,11 @@
 pragma circom 2.1.6;
 
 /// @function log2Ceil
-/// @notice This function actually calculates `ceil(log2(a+2))`
+/// @notice Calculate log2 of a number and round it up
 /// @param a The input value
 /// @return The result of the log2Ceil
 function log2Ceil(a) {
-    var n = a + 1;
+    var n = a - 1;
     var r = 0;
 
     while (n > 0) {