diff --git a/src/gates/ModularMultiplicationGates.js b/src/gates/ModularMultiplicationGates.js
index 239aeacc..8e40a068 100644
--- a/src/gates/ModularMultiplicationGates.js
+++ b/src/gates/ModularMultiplicationGates.js
@@ -50,7 +50,7 @@ const MODULAR_INVERSE_SHADER_CODE = `
         if (r.y != 1.0) {
             return -1.0;
         }
-        return mod(mod(s.y, modulus) + modulus, modulus);
+        return floor(mod(floor(mod(s.y + 0.5, modulus)) + modulus + 0.5, modulus));
     }
 `;
 
@@ -70,7 +70,7 @@ const POW_MOD_SHADER_CODE = `
 
         float f = 1.0;
         for (int k = 0; k < ${Config.MAX_WIRE_COUNT}; k++) {
-            if (mod(exponent, 2.0) == 1.0) {
+            if (floor(mod(exponent + 0.5, 2.0)) == 1.0) {
                 exponent -= 1.0;
                 f = big_mul_mod(f, base, modulus);
             }
@@ -169,7 +169,7 @@ const MODULAR_MULTIPLICATION_SHADER = ketShaderPermute(
     `
         float input_a = read_input_A();
         float modulus = read_input_R();
-        input_a = mod(input_a, modulus);
+        input_a = floor(mod(input_a + 0.5, modulus));
         float v = modular_multiplicative_inverse(input_a, modulus);
         if (v == -1.0 || out_id >= modulus) {
             return out_id;
@@ -186,7 +186,7 @@ const MODULAR_INVERSE_MULTIPLICATION_SHADER = ketShaderPermute(
     `
         float input_a = read_input_A();
         float modulus = read_input_R();
-        input_a = mod(input_a, modulus);
+        input_a = floor(mod(input_a + 0.5, modulus));
         if (modular_multiplicative_inverse(input_a, modulus) == -1.0 || out_id >= modulus) {
             return out_id;
         }
diff --git a/src/gates/ModularMultiplyAccumulateGates.js b/src/gates/ModularMultiplyAccumulateGates.js
index 9ea58fc6..0f2b36d8 100644
--- a/src/gates/ModularMultiplyAccumulateGates.js
+++ b/src/gates/ModularMultiplyAccumulateGates.js
@@ -36,7 +36,7 @@ const MODULAR_MULTIPLY_ACCUMULATE_SHADER = ketShaderPermute(
 
         float d = big_mul_mod(factor * a, b, r);
 
-        float in_id = mod(out_id - d, r);
+        float in_id = floor(mod(out_id - d + 0.5, r));
         if (in_id < 0.0) {
             in_id += r;
         }
diff --git a/src/gates/MultiplyAccumulateGates.js b/src/gates/MultiplyAccumulateGates.js
index e5f7f2d0..5bb9c486 100644
--- a/src/gates/MultiplyAccumulateGates.js
+++ b/src/gates/MultiplyAccumulateGates.js
@@ -64,7 +64,7 @@ const MULTIPLY_ACCUMULATE_SHADER = ketShaderPermute(
     `
         float d1 = read_input_A();
         float d2 = read_input_B();
-        float d = mod(big_mul_mod(d1, d2, span)*factor, span);
+        float d = floor(mod(big_mul_mod(d1, d2, span)*factor + 0.5, span));
         return mod(out_id + span - d, span);`);
 
 MultiplyAccumulateGates.Legacy_MultiplyAddFamily = Gate.buildFamily(3, 16, (span, builder) => builder.
diff --git a/test/gates/AmplitudeDisplay.test.js b/test/gates/AmplitudeDisplay.test.js
index ca597e83..c5b403e3 100644
--- a/test/gates/AmplitudeDisplay.test.js
+++ b/test/gates/AmplitudeDisplay.test.js
@@ -44,7 +44,7 @@ suite.testUsingWebGL("amplitudesToPolarKets", () => {
         25,new Complex(3,4).phase(),25,0,
         2,Math.PI*3/4,2,0,
         0.25,Math.PI/2,0.25,0
-    ]), 0.0001);
+    ]), 0.001);
     input.deallocByDepositingInPool();
 });