Fixed compilation error in kernel with CustomIntegrator (#3187)

platforms/common/src/ExpressionUtilities.cpp

@@ -698,9 +698,16 @@ void ExpressionUtilities::processExpression(stringstream& out, const ExpressionT
         case Operation::POWER_CONSTANT:
         {
             double exponent = dynamic_cast<const Operation::PowerConstant*>(&node.getOperation())->getValue();
-            if (exponent == 0.0)
+            if (exponent == 0.0) {
+                if (isVecType)
+                    out << "make_" << tempType << "(1.0f)";
+                else
                     out << "1.0f";
+            }
             else if (exponent == (int) exponent) {
+                if (isVecType)
+                    out << "make_" << tempType << "(0.0f);\n";
+                else
                     out << "0.0f;\n";
                 temps.push_back(make_pair(node, name));
                 hasRecordedNode = true;
@@ -727,7 +734,7 @@ void ExpressionUtilities::processExpression(stringstream& out, const ExpressionT
                     }
                 }
                 out << "{\n";
-                out << "real multiplier = " << (exponent < 0.0 ? "RECIP(" : "(") << getTempName(node.getChildren()[0], temps) << ");\n";
+                out << tempType << " multiplier = " << (exponent < 0.0 ? "RECIP(" : "(") << getTempName(node.getChildren()[0], temps) << ");\n";
                 bool done = false;
                 while (!done) {
                     done = true;

tests/TestCustomIntegrator.h

@@ -543,7 +543,7 @@ void testPerDofVariables() {
     integrator.addComputePerDof("v", "v+dt*f/m");
     integrator.addComputePerDof("x", "x+dt*v");
     integrator.addComputePerDof("pos", "x");
-    integrator.addComputePerDof("computed", "step(v)*log(x^2)");
+    integrator.addComputePerDof("computed", "step(v)*log(x^4)");
     Context context(system, integrator, platform);
     context.setPositions(positions);
     vector<Vec3> initialValues(numParticles);
@@ -571,7 +571,7 @@ void testPerDofVariables() {
                 }
                 else {
                     double v = state.getPositions()[j][k];
-                    ASSERT_EQUAL_TOL(log(v*v), values[j][k], 1e-5);
+                    ASSERT_EQUAL_TOL(log(v*v*v*v), values[j][k], 1e-5);
                 }
             }
     }