On Sat, 5 Sep 2020, at 21:21, Bob Bridges wrote:
> Going back to the beginning, Gil: SQRT(X**TWO+Y**TWO) looks like
> ~exactly~ the sort of thing that oughta be made a constant rather than
> being coded more than once. That is, if X, Y and TWO all constants
> themselves; and if they are not
On Sat, 5 Sep 2020, at 21:09, Bob Bridges wrote:
> I've never done that, but I have done something like it:
>
> str=word('true false',(0-fx)+2)
Why (0-fx)+2when 2-fxis simpler?
> (If I have to explain it, it just proves I should never write it that
> way in the first place.
We once had a database so valuable that it was mirrored to a remote site where
8, 16, and 24 hour PIT copies of it were made. We could do forward recovery
from tape if needed. This was more to protect against an application trashing
the data than anything else. It was hoped that data
When you care about efficiency, I'd think this would be better:
const=4/3*3.14159E0 /* in the initialization */
volume=const*radius**3 /* inside the loop */
---
Bob Bridges, robhbrid...@gmail.com, cell 336 382-7313
/* Things may come to those who wait, but only those things left behind by
Going back to the beginning, Gil: SQRT(X**TWO+Y**TWO) looks like ~exactly~ the
sort of thing that oughta be made a constant rather than being coded more than
once. That is, if X, Y and TWO all constants themselves; and if they are not
then this isn't an example of what you're talking about.
On Sat, 5 Sep 2020 23:36:37 +0100, Rupert Reynolds wrote:
>Writing Rexx for myself (therefore no local standards to follow) I had to
>set an internal boolean in a few places.
>So I started it with
>TRUE = (1=1)
>FALSE = \TRUE
>
Now you have them; how are they useful? (Examples?)
>That's partly
John,
But what happens if the virtual tape environment itself was over-written? That
is where the concept of "virtual WORM" devices can help. A virtual WORM volume
cannot be over-written. And if your tape management system itself is protected,
the tapes will not be scratched until they should
I have a copy of the manual "Amdahl MVS/SP Assist Release 1.0 Software Logic
Manual" L1020.0-02A from October 1982. I recall we used this to run MVS/SP 1.3
on old 370/158 machines. It would simulate the entire set of "new" cross-memory
services instructions, such as MVCP, MVCS, PC, PT and so
Writing Rexx for myself (therefore no local standards to follow) I had to
set an internal boolean in a few places.
So I started it with
TRUE = (1=1)
FALSE = \TRUE
That's partly because I couldn't find doc on Rexx standards (no WWW yet)
and I didn't like to assume that 1 and 0 were always valid
And to take this one step further (really one step too far), IBM boxes
(DS and TS) have a built-in function called Secure Data Overwrite, so
that before an old, replaced box goes out the door, the user can get a
certification that all their old data is truly overwritten with multiple
passes.
Gotta side with Robin on that one.
---
Bob Bridges, robhbrid...@gmail.com, cell 336 382-7313
/* Law #37 of combat operations: Anything you do can get you killed, including
nothing. */
-Original Message-
From: IBM Mainframe Discussion List [mailto:IBM-MAIN@LISTSERV.UA.EDU] On Behalf
I've never done that, but I have done something like it:
str=word('true false',(0-fx)+2)
...where fx is Boolean. I hope I've done it only in programs I wrote for my
own use. But I sometimes write a tool for myself, then move it to a public
library on request, so that monster may be out
On Sat, 5 Sep 2020 16:09:32 -0400, Bob Bridges wrote:
>
> str=word('true false',(0-fx)+2)
>
>...where fx is Boolean.
>
My use of COPIES() was to save 2 lines of code while knowing that
the function call/return overhead is large and IF would perform better.
> if fx then str='true'; else
We see 1.3 on peak hours.
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If I were to consider this (which I don't because my shop _is_ going away
1Q2021), what I would do is have a "golden image" (aka sysprog sandbox or
the GI) in a different LPAR. This image would have access to all attached
devices, including sharing a virtual tape environment. But the "core"
On Fri, 4 Sep 2020 09:22:09 -0700, Ed Jaffe wrote:
>IMHO, if you need additional zIIP capacity for a production workload, it
>probably makes more sense to configure another zIIP core online than it
>does to enable MT=2.
Agreed. SMT is a good thing to keep in your pocket for the emergency of
On 2020-09-04 18:36, Paul Gilmartin wrote:
On Fri, 4 Sep 2020 20:38:29 +, Robert Prins wrote:
On 2020-09-04 17:01, Paul Gilmartin wrote:
I see everything twice:
On Fri, 4 Sep 2020 19:05:32 +, Robert Prins wrote:
On Fri, 4 Sep 2020 19:06:49 +, Robert Prins wrote:
Yes, problems
On Sat, 5 Sep 2020 12:06:49 +, Robert Prins wrote:
>
>... definitely not to keep myself in the picture.
>The simple fact is that I hate it that 'doze displays timestamps different in
>different time zones. So my TZ is UTC.
>
The time is different in different timezones. What do you expect?
On 2020-09-06 11:50, Seymour J Metz wrote:
Eschew obfuscation. Either just use 0 and one, or write
false=0;true=1. Similarly, for PL/I either just use '0'b and '1'b or
write false='0'b;true='1'b;.
VALUE is a good alternative also.
When you're dealing with small integers that stand for themselves, theres
neither benfit nor harm for making them named constants. It's "magic numbers"
that you need to avoid, e.g., approximations, exchange rates.
--
Shmuel (Seymour J.) Metz
http://mason.gmu.edu/~smetz3
Don't most compilers these days do constant folding?
--
Shmuel (Seymour J.) Metz
http://mason.gmu.edu/~smetz3
From: IBM Mainframe Discussion List on behalf of Bob
Bridges
Sent: Saturday, September 5, 2020 4:18 PM
To: IBM-MAIN@LISTSERV.UA.EDU
Subject:
On Sat, 5 Sep 2020 08:13:42 +1000, Robin Vowels wrote:
>
>As for writing formulas, I prefer to follow a well-known formula, thus:
>
>volume = 4/3 * 3.14159 * radius**3
>
Beware! Than might left-associate as:
volume = ( 4/3 ) * 3.14159 * radius**3
... and the quotient of integers, 4/3, is 1.
The issue in contention is the wording of the text, not its location. I never
claimed that it was in the right manual.
--
Shmuel (Seymour J.) Metz
http://mason.gmu.edu/~smetz3
From: IBM Mainframe Discussion List on behalf of
Robin Vowels
Sent:
Eschew obfuscation. Either just use 0 and one, or write false=0;true=1.
Similarly, for PL/I either just use '0'b and '1'b or write
false='0'b;true='1'b;.
--
Shmuel (Seymour J.) Metz
http://mason.gmu.edu/~smetz3
From: IBM Mainframe Discussion List on
That's obfuscation.
If it's in a loop, I'd expect the compiler to move the constant part outside
of the loop,
or to evaluate the constant part at compilation time.
In any case, the more efficient form eliminates the division 4/3,
avoiding the avaluation in fixed-point form (and the conversion
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