From 50fab9feb3b80b7d5ac1e94df9af68cad4aaabe0 Mon Sep 17 00:00:00 2001 From: Remco Bloemen Date: Wed, 22 Aug 2018 12:22:58 -0700 Subject: Improve getPartialAmountCeil docs --- packages/contracts/src/2.0.0/protocol/Exchange/libs/LibMath.sol | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'packages') diff --git a/packages/contracts/src/2.0.0/protocol/Exchange/libs/LibMath.sol b/packages/contracts/src/2.0.0/protocol/Exchange/libs/LibMath.sol index c4aa2abb5..d123c55a1 100644 --- a/packages/contracts/src/2.0.0/protocol/Exchange/libs/LibMath.sol +++ b/packages/contracts/src/2.0.0/protocol/Exchange/libs/LibMath.sol @@ -65,9 +65,9 @@ contract LibMath is "DIVISION_BY_ZERO" ); - // SafeDiv rounds down. To use it to round up we need to add - // denominator - 1. This causes anything less than an exact multiple - // of denominator to be rounded up. + // safeDiv computes `floor(a / b)`. We use the identity (a, b integer): + // ceil(a / b) = floor((a + b - 1) / b) + // To implement `ceil(a / b)` using safeDiv. partialAmount = safeDiv( safeAdd(safeMul(numerator, target), safeSub(denominator, 1)), denominator -- cgit v1.2.3