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#N canvas 11 8 937 643 10;
#X msg 43 113 bang;
#X msg 18 91 bang;
#X obj 18 135 timer;
#X obj 25 15 timer;
#X floatatom 18 157 0 0 0;
#X text 90 159 Output is in milliseconds;
#X text 65 16 -- measure logical time;
#X text 53 91 Click here to start or reset;
#X text 13 44 The [timer] object measures elapsed logical time. Logical
time moves forward as if all computation were instantaneous and as
if all [delay] and [metro] objects were exact.;
#X text 11 185 [timer] works like essentially like a stop-watch. Once
it starts \, you can continue to "poll" the [timer] to view the elapsed
time.;
#X text 81 114 Click here to get elapsed logical time. Click again...and
again...to see periodic measurements from the start or reset time.
;
#X text 10 282 As stated above \, [timer] measures "logical" time.
This value may be slightly different that CPU time or "real" time.
PD offers two objects which measure CPU time and "real" time. See the
reference documents for those objects for more information.;
#X obj 52 545 time_measurements;
#X obj 52 441 bng 15 250 50 0 empty empty empty 0 -6 0 8 -262144 -1
-1;
#X floatatom 17 572 0 0 0;
#X floatatom 108 585 0 0 0;
#X floatatom 175 573 0 0 0;
#X text 11 358 In the example below \, I've created an abstraction
which will force each of PD's stop-watches \, [timer] [cputime] and
[realtime] to measure various processes and report the elapsed time.
Click on each [bng] to begin the process and wait for the results.
Notice the discrepancies in the results.;
#X text 15 587 Logical Time;
#X text 173 587 Real Time;
#X text 107 601 CPU Time;
#X obj 67 477 bng 15 250 50 0 empty empty empty 0 -6 0 8 -262144 -1
-1;
#X text 72 435 1 Measures elapsed time between two "bangs" from a [trigger]
object.;
#X text 87 469 2 Measures the amount of time PD requires to turn on
DSP and start an oscillator.;
#X obj 445 484 bng 15 250 50 0 empty empty empty 0 -6 0 8 -262144 -1
-1;
#X obj 445 17 bng 15 250 50 0 empty empty empty 0 -6 0 8 -262144 -1
-1;
#X text 472 36 WHY THE DISCREPANCIES BETWEEN CLOCKS?;
#X text 475 59 In a fantasy world \, computers could exist somehow
beyond the restrictions of time and digital computation could be performed
in ZERO time. However \, that is not the case. Instead \, every process
within PD and within your operating system requires at least a few
nanoseconds of your CPU's time.;
#X obj 111 509 bng 15 250 50 0 empty empty empty 0 -6 0 8 -262144 -1
-1;
#X text 476 144 The [timer] object is like a clock that is not constrained
to the regular laws of physics and the universal space-time continuum.
It reports "time" measurements as only PD can see them!;
#X text 477 204 The [cputime] object is like a clock that measures
how much time your CPU actually required to carry out your request.
Keep in mind however that your CPU is busy doing many things simoultaneously
\, so even though a process might take 5 minutes to complete \, your
CPU does not pay full attention to that process for the entire 5 minutes.
Instead \, it simply begins the process \, then refers back to that
process from time to time until the it is complete. In other cases
\, your CPU might require a full 5 minutes while PD might report that
merely a few milliseconds have passed. This type of discrepancy depends
heavily on your computer's hardware and the type of processing it is
performing.;
#X text 478 368 The [realtime] object is as much like your own wrist
watch as PD can possibly manage. It measures time according to your
operating system's internal clock.;
#N canvas 0 0 454 304 related_objects_from_other_libraries 0;
#X text 27 63 These objects are offered in PD only if you have downloaded
and properly installed the appropriate library. These objects may or
may not exist in a single library.;
#X text 26 112 The best places to find information about PD's libraries
is:;
#X text 23 134 www.puredata.org and click on "Downloads" then "Software"
;
#X text 25 149 or;
#X text 25 164 iem.kug.ac.at/pdb/;
#X obj 44 24 t3_timer;
#X text 469 589 This document was updated for PD version 0.35 test
26 by Dave Sabine as part of a project called pddp proposed by Krzysztof
Czaja to build comprehensive documentation for PD.;
#X restore 505 476 pd related_objects_from_other_libraries;
#X text 309 580 This document was updated for PD version 0.35 test
28 by Dave Sabine as part of a project called pddp proposed by Krzysztof
Czaja to build comprehensive documentation for PD.;
#X text 11 232 The odd aspect about comparing [timer] to a stop-watch
is that a stop-watch can be stopped! [timer] can only be started or
reset. It cannot be stopped.;
#X obj 625 445 metro;
#X text 504 422 RELATED OBJECTS;
#X obj 504 446 cputime;
#X obj 562 445 realtime;
#X text 132 501 3 Measures the amount of time PD requires count to
three...please wait for approximately 3 seconds.;
#X connect 0 0 2 1;
#X connect 1 0 2 0;
#X connect 2 0 4 0;
#X connect 12 0 14 0;
#X connect 12 1 15 0;
#X connect 12 2 16 0;
#X connect 13 0 12 0;
#X connect 21 0 12 1;
#X connect 25 0 24 0;
#X connect 28 0 12 2;
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