[9front] [patch] add log2 to ape

9front - general discussion about 9front
 help / color / mirror / Atom feed

* [9front] [patch] add log2 to ape
@ 2020-12-06 16:56 Iruatã Souza
  2020-12-06 18:49 ` ori
  0 siblings, 1 reply; 4+ messages in thread
From: Iruatã Souza @ 2020-12-06 16:56 UTC (permalink / raw)
  To: 9front

Hi,

This adds log2 to APE. It is defined in posix and at least Lua expects it.

diff -r 543ad076adbc sys/src/ape/lib/ap/math/log.c
--- a/sys/src/ape/lib/ap/math/log.c	Sun Dec 06 15:08:23 2020 +0100
+++ b/sys/src/ape/lib/ap/math/log.c	Sun Dec 06 17:45:18 2020 +0100
@@ -10,7 +10,7 @@
 #include <math.h>
 #include <errno.h>

-#define	log2    0.693147180559945309e0
+#define	_log2   0.693147180559945309e0
 #define	ln10o1  .4342944819032518276511
 #define	sqrto2  0.707106781186547524e0
 #define	p0      -.240139179559210510e2
@@ -46,7 +46,7 @@

 	temp = ((p3*zsq + p2)*zsq + p1)*zsq + p0;
 	temp = temp/(((zsq + q2)*zsq + q1)*zsq + q0);
-	temp = temp*z + exp*log2;
+	temp = temp*z + exp*_log2;
 	return temp;
 }

@@ -60,3 +60,9 @@
 	}
 	return log(arg) * ln10o1;
 }
+
+double
+log2(double arg)
+{
+	return log(x)/_log2;
+}

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [9front] [patch] add log2 to ape
  2020-12-06 16:56 [9front] [patch] add log2 to ape Iruatã Souza
@ 2020-12-06 18:49 ` ori
  2020-12-07 10:16   ` Iruatã Souza
  0 siblings, 1 reply; 4+ messages in thread
From: ori @ 2020-12-06 18:49 UTC (permalink / raw)
  To: iru.muzgo, 9front

Quoth Iruatã Souza <iru.muzgo@gmail.com>:
> Hi,
> 
> +
> +double
> +log2(double arg)
> +{
> +	return log(x)/_log2;
> +}
> 

In error cases, this divides the error return
by log2. I suspect we don't want to do that.

I'd also rather name all of the constants
consistently. Maybe uppercase the initial
character, instead of giving one of them
an _ prefix.

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [9front] [patch] add log2 to ape
  2020-12-06 18:49 ` ori
@ 2020-12-07 10:16   ` Iruatã Souza
  2020-12-07 11:34     ` Iruatã Souza
  0 siblings, 1 reply; 4+ messages in thread
From: Iruatã Souza @ 2020-12-07 10:16 UTC (permalink / raw)
  To: ori, 9front

On 06/12/2020 19:49, ori@eigenstate.org wrote:
> In error cases, this divides the error return
> by log2. I suspect we don't want to do that.
> 
> I'd also rather name all of the constants
> consistently. Maybe uppercase the initial
> character, instead of giving one of them
> an _ prefix.

The patch is simply wrong, it doesn't even compile correctly!

Sorry for the noise, here is a better one.

diff -r 3497ab777d56 amd64/include/ape/math.h
--- a/amd64/include/ape/math.h	Mon Dec 07 00:36:41 2020 +0100
+++ b/amd64/include/ape/math.h	Mon Dec 07 11:11:22 2020 +0100
@@ -26,6 +26,7 @@
 extern double ldexp(double, int);
 extern double log(double);
 extern double log10(double);
+extern double log2(double);
 extern double modf(double, double *);
 extern double pow(double, double);
 extern double sqrt(double);
diff -r 3497ab777d56 sys/src/ape/lib/ap/math/log.c
--- a/sys/src/ape/lib/ap/math/log.c	Mon Dec 07 00:36:41 2020 +0100
+++ b/sys/src/ape/lib/ap/math/log.c	Mon Dec 07 11:11:22 2020 +0100
@@ -10,16 +10,16 @@
 #include <math.h>
 #include <errno.h>

-#define	log2    0.693147180559945309e0
-#define	ln10o1  .4342944819032518276511
-#define	sqrto2  0.707106781186547524e0
-#define	p0      -.240139179559210510e2
-#define	p1      0.309572928215376501e2
-#define	p2      -.963769093377840513e1
-#define	p3      0.421087371217979714e0
-#define	q0      -.120069589779605255e2
-#define	q1      0.194809660700889731e2
-#define	q2      -.891110902798312337e1
+#define	Log2   0.693147180559945309e0
+#define	Ln10o1  .4342944819032518276511
+#define	Sqrto2  0.707106781186547524e0
+#define	P0      -.240139179559210510e2
+#define	P1      0.309572928215376501e2
+#define	P2      -.963769093377840513e1
+#define	P3      0.421087371217979714e0
+#define	Q0      -.120069589779605255e2
+#define	Q1      0.194809660700889731e2
+#define	Q2      -.891110902798312337e1

 double
 log(double arg)
@@ -36,7 +36,7 @@
 		x *= 2;
 		exp--;
 	}
-	if(x < sqrto2) {
+	if(x < Sqrto2) {
 		x *= 2;
 		exp--;
 	}
@@ -44,9 +44,9 @@
 	z = (x-1) / (x+1);
 	zsq = z*z;

-	temp = ((p3*zsq + p2)*zsq + p1)*zsq + p0;
-	temp = temp/(((zsq + q2)*zsq + q1)*zsq + q0);
-	temp = temp*z + exp*log2;
+	temp = ((P3*zsq + P2)*zsq + P1)*zsq + P0;
+	temp = temp/(((zsq + Q2)*zsq + Q1)*zsq + Q0);
+	temp = temp*z + exp*Log2;
 	return temp;
 }

@@ -58,5 +58,16 @@
 		errno = (arg==0)? ERANGE : EDOM;
 		return -HUGE_VAL;
 	}
-	return log(arg) * ln10o1;
+	return log(arg) * Ln10o1;
 }
+
+double
+log2(double arg)
+{
+	if(arg <= 0) {
+		errno = (arg==0)? ERANGE : EDOM;
+		return -HUGE_VAL;
+	}
+
+	return log(arg)/Log2;
+}

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [9front] [patch] add log2 to ape
  2020-12-07 10:16   ` Iruatã Souza
@ 2020-12-07 11:34     ` Iruatã Souza
  0 siblings, 0 replies; 4+ messages in thread
From: Iruatã Souza @ 2020-12-07 11:34 UTC (permalink / raw)
  To: ori, 9front

On 07/12/2020 11:16, Iruatã Souza wrote:
> On 06/12/2020 19:49, ori@eigenstate.org wrote:
>> In error cases, this divides the error return
>> by log2. I suspect we don't want to do that.
>>
>> I'd also rather name all of the constants
>> consistently. Maybe uppercase the initial
>> character, instead of giving one of them
>> an _ prefix.
> 
> The patch is simply wrong, it doesn't even compile correctly!
> 
> Sorry for the noise, here is a better one.
> 

Now changing ape/math.h for all architectures.


diff -r 3497ab777d56 386/include/ape/math.h
--- a/386/include/ape/math.h	Mon Dec 07 00:36:41 2020 +0100
+++ b/386/include/ape/math.h	Mon Dec 07 12:29:28 2020 +0100
@@ -26,6 +26,7 @@
 extern double ldexp(double, int);
 extern double log(double);
 extern double log10(double);
+extern double log2(double);
 extern double modf(double, double *);
 extern double pow(double, double);
 extern double sqrt(double);
diff -r 3497ab777d56 68020/include/ape/math.h
--- a/68020/include/ape/math.h	Mon Dec 07 00:36:41 2020 +0100
+++ b/68020/include/ape/math.h	Mon Dec 07 12:29:28 2020 +0100
@@ -26,6 +26,7 @@
 extern double ldexp(double, int);
 extern double log(double);
 extern double log10(double);
+extern double log2(double);
 extern double modf(double, double *);
 extern double pow(double, double);
 extern double sqrt(double);
diff -r 3497ab777d56 amd64/include/ape/math.h
--- a/amd64/include/ape/math.h	Mon Dec 07 00:36:41 2020 +0100
+++ b/amd64/include/ape/math.h	Mon Dec 07 12:29:28 2020 +0100
@@ -26,6 +26,7 @@
 extern double ldexp(double, int);
 extern double log(double);
 extern double log10(double);
+extern double log2(double);
 extern double modf(double, double *);
 extern double pow(double, double);
 extern double sqrt(double);
diff -r 3497ab777d56 arm/include/ape/math.h
--- a/arm/include/ape/math.h	Mon Dec 07 00:36:41 2020 +0100
+++ b/arm/include/ape/math.h	Mon Dec 07 12:29:28 2020 +0100
@@ -26,6 +26,7 @@
 extern double ldexp(double, int);
 extern double log(double);
 extern double log10(double);
+extern double log2(double);
 extern double modf(double, double *);
 extern double pow(double, double);
 extern double sqrt(double);
diff -r 3497ab777d56 arm64/include/ape/math.h
--- a/arm64/include/ape/math.h	Mon Dec 07 00:36:41 2020 +0100
+++ b/arm64/include/ape/math.h	Mon Dec 07 12:29:28 2020 +0100
@@ -26,6 +26,7 @@
 extern double ldexp(double, int);
 extern double log(double);
 extern double log10(double);
+extern double log2(double);
 extern double modf(double, double *);
 extern double pow(double, double);
 extern double sqrt(double);
diff -r 3497ab777d56 mips/include/ape/math.h
--- a/mips/include/ape/math.h	Mon Dec 07 00:36:41 2020 +0100
+++ b/mips/include/ape/math.h	Mon Dec 07 12:29:28 2020 +0100
@@ -26,6 +26,7 @@
 extern double ldexp(double, int);
 extern double log(double);
 extern double log10(double);
+extern double log2(double);
 extern double modf(double, double *);
 extern double pow(double, double);
 extern double sqrt(double);
diff -r 3497ab777d56 power/include/ape/math.h
--- a/power/include/ape/math.h	Mon Dec 07 00:36:41 2020 +0100
+++ b/power/include/ape/math.h	Mon Dec 07 12:29:28 2020 +0100
@@ -26,6 +26,7 @@
 extern double ldexp(double, int);
 extern double log(double);
 extern double log10(double);
+extern double log2(double);
 extern double modf(double, double *);
 extern double pow(double, double);
 extern double sqrt(double);
diff -r 3497ab777d56 sparc/include/ape/math.h
--- a/sparc/include/ape/math.h	Mon Dec 07 00:36:41 2020 +0100
+++ b/sparc/include/ape/math.h	Mon Dec 07 12:29:28 2020 +0100
@@ -26,6 +26,7 @@
 extern double ldexp(double, int);
 extern double log(double);
 extern double log10(double);
+extern double log2(double);
 extern double modf(double, double *);
 extern double pow(double, double);
 extern double sqrt(double);
diff -r 3497ab777d56 sparc64/include/ape/math.h
--- a/sparc64/include/ape/math.h	Mon Dec 07 00:36:41 2020 +0100
+++ b/sparc64/include/ape/math.h	Mon Dec 07 12:29:28 2020 +0100
@@ -26,6 +26,7 @@
 extern double ldexp(double, int);
 extern double log(double);
 extern double log10(double);
+extern double log2(double);
 extern double modf(double, double *);
 extern double pow(double, double);
 extern double sqrt(double);
diff -r 3497ab777d56 sys/src/ape/lib/ap/math/log.c
--- a/sys/src/ape/lib/ap/math/log.c	Mon Dec 07 00:36:41 2020 +0100
+++ b/sys/src/ape/lib/ap/math/log.c	Mon Dec 07 12:29:28 2020 +0100
@@ -10,16 +10,16 @@
 #include <math.h>
 #include <errno.h>

-#define	log2    0.693147180559945309e0
-#define	ln10o1  .4342944819032518276511
-#define	sqrto2  0.707106781186547524e0
-#define	p0      -.240139179559210510e2
-#define	p1      0.309572928215376501e2
-#define	p2      -.963769093377840513e1
-#define	p3      0.421087371217979714e0
-#define	q0      -.120069589779605255e2
-#define	q1      0.194809660700889731e2
-#define	q2      -.891110902798312337e1
+#define	Log2   0.693147180559945309e0
+#define	Ln10o1  .4342944819032518276511
+#define	Sqrto2  0.707106781186547524e0
+#define	P0      -.240139179559210510e2
+#define	P1      0.309572928215376501e2
+#define	P2      -.963769093377840513e1
+#define	P3      0.421087371217979714e0
+#define	Q0      -.120069589779605255e2
+#define	Q1      0.194809660700889731e2
+#define	Q2      -.891110902798312337e1

 double
 log(double arg)
@@ -36,7 +36,7 @@
 		x *= 2;
 		exp--;
 	}
-	if(x < sqrto2) {
+	if(x < Sqrto2) {
 		x *= 2;
 		exp--;
 	}
@@ -44,9 +44,9 @@
 	z = (x-1) / (x+1);
 	zsq = z*z;

-	temp = ((p3*zsq + p2)*zsq + p1)*zsq + p0;
-	temp = temp/(((zsq + q2)*zsq + q1)*zsq + q0);
-	temp = temp*z + exp*log2;
+	temp = ((P3*zsq + P2)*zsq + P1)*zsq + P0;
+	temp = temp/(((zsq + Q2)*zsq + Q1)*zsq + Q0);
+	temp = temp*z + exp*Log2;
 	return temp;
 }

@@ -58,5 +58,16 @@
 		errno = (arg==0)? ERANGE : EDOM;
 		return -HUGE_VAL;
 	}
-	return log(arg) * ln10o1;
+	return log(arg) * Ln10o1;
 }
+
+double
+log2(double arg)
+{
+	if(arg <= 0) {
+		errno = (arg==0)? ERANGE : EDOM;
+		return -HUGE_VAL;
+	}
+
+	return log(arg)/Log2;
+}

^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2020-12-07 11:37 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-12-06 16:56 [9front] [patch] add log2 to ape Iruatã Souza
2020-12-06 18:49 ` ori
2020-12-07 10:16   ` Iruatã Souza
2020-12-07 11:34     ` Iruatã Souza

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).