# CVS difference for ais/ai-00156.txt

Differences between 1.7 and version 1.8
Log of other versions for file ais/ai-00156.txt

```--- ais/ai-00156.txt	2000/07/13 04:31:29	1.7
+++ ais/ai-00156.txt	2000/08/01 05:39:34	1.8
@@ -1,4 +1,4 @@
-!standard G.1.1    (55)                               00-06-19  AI95-00156/06
+!standard G.1.1    (55)                               00-07-31  AI95-00156/07
!class binding interpretation 96-09-04
!status Corrigendum 2000 99-05-27
!status WG9 approved 98-06-12
@@ -48,16 +48,15 @@

Here is a proof by example that the given method is incorrect:

-Assume that the method described in the standard is correct.  Let a
-complex number X=0+I.  Let an integer n=-1
+Assume that the method described in the standard is correct. Let a
+complex number X = 0+I. Let an integer n = -1. Then

-X**n=1/i=-i
+X**n = 1/i = -i

-argument(X)=pi/2 and n is negative.  So, according to G.1.1(55),
-argument(X**n)=(pi/2)/|-1|=pi/2
+argument(X) = pi/2 and n is negative.  So, according to G.1.1(55),
+argument(X**n) = (pi/2)/|-1| = pi/2,
+but argument(X**n) = argument(-i) = -pi/2

-but, argument(X**n)=argument(-i)=-pi/2
-
Obviously, pi/2 is not equal to -pi/2 (even as an angle); i.e. a
No zero-valued complex numbers were involved (they can mess things up).
@@ -70,7 +69,7 @@
Implementations may obtain the result of exponentiation of a complex or
pure-imaginary operand by repeated complex multiplication, with arbitrary
association of the factors and with a possible final complex reciprocation
-(when the exponent is negative).  Implementations are also permitted to
+(when the exponent is negative). Implementations are also permitted to
obtain the result of exponentiation of a complex operand, but not of a
pure-imaginary operand, by converting the left operand to a polar
representation; exponentiating the modulus by the given exponent; multiplying
@@ -89,7 +88,7 @@
pure-imaginary operand, by converting the left operand to a polar
representation, exponentiating the modulus by the given exponent,
multiplying the argument by the given exponent, and reconverting to a
-Cartesian representation. Because of this implementation freedom, no
+cartesian representation. Because of this implementation freedom, no
accuracy requirement is imposed on complex exponentiation (except for the
prescribed results given above, which apply regardless of the
implementation method chosen).
```

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