cyb70289 commented on a change in pull request #9841:
URL: https://github.com/apache/arrow/pull/9841#discussion_r605699158



##########
File path: cpp/src/arrow/compute/kernels/scalar_arithmetic.cc
##########
@@ -233,6 +235,282 @@ struct DivideChecked {
   }
 };
 
+struct Power {
+  template <typename T, typename Arg0, typename Arg1>
+  static enable_if_signed_integer<T> Call(KernelContext* ctx, Arg0 left, Arg1 
right) {
+    Arg0 result = 1;
+    if (left == 0) {
+      if (right < 0) {
+        ARROW_PREDICT_FALSE(MultiplyWithOverflow(2, 
std::numeric_limits<Arg0>::max(), &result));
+        ctx->SetStatus(Status::Invalid("divide by zero"));
+        return result;
+      } else if (right == 0) {
+        return 1;
+      }
+      return 0;
+    } else if (right == INFINITY && abs(left) > 1) {
+      ARROW_PREDICT_FALSE(MultiplyWithOverflow(2, 
std::numeric_limits<Arg0>::max(), &result));
+      return result;
+    } else if (right == -INFINITY && abs(left) > 1) {
+      return 0;
+    }
+
+    if (right > 0) {
+      for (Arg1 i = 0; i < right; i++) {
+        if (ARROW_PREDICT_FALSE(MultiplyWithOverflow(result, left, &result))) {
+          ctx->SetStatus(Status::Invalid("overflow"));
+        }
+      }
+    } else {
+      for (Arg1 i = 0; i < -right; i++) {

Review comment:
       It will be easy if we support an option to set explicitly the return 
value type, like numpy `dtype` .
   Otherwise, we have to scan the whole exponent array to see if there're 
negative exponents before deciding the output type.




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