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#N canvas 0 0 555 619 10;
#X obj 0 595 cnv 15 552 21 empty \$0-pddp.cnv.footer empty 20 12 0
14 -228856 -66577 0;
#X obj 0 0 cnv 15 552 40 empty \$0-pddp.cnv.header realtime 3 12 0
18 -204280 -1 0;
#X obj 0 376 cnv 3 550 3 empty \$0-pddp.cnv.inlets inlets 8 12 0 13
-228856 -1 0;
#N canvas 51 243 494 372 META 0;
#X text 12 125 LIBRARY internal;
#X text 12 165 WEBSITE http://crca.ucsd.edu/~msp/;
#X text 12 185 RELEASE_DATE 2009-06-12;
#X text 12 25 LICENSE SIBSD;
#X text 12 145 AUTHOR Miller Puckette;
#X text 12 205 HELP_PATCH_AUTHORS This help patch 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. Jonathan Wilkes revised the patch to conform to the PDDP template
for Pd version 0.42.;
#X text 12 5 KEYWORDS control time;
#X text 12 45 DESCRIPTION ask operating system for elapsed real time
;
#X text 12 65 INLET_0 bang;
#X text 12 85 INLET_1 bang;
#X text 12 105 OUTLET_0 float;
#X restore 500 597 pd META;
#X obj 0 473 cnv 3 550 3 empty \$0-pddp.cnv.outlets outlets 8 12 0
13 -228856 -1 0;
#X obj 0 510 cnv 3 550 3 empty \$0-pddp.cnv.argument arguments 8 12
0 13 -228856 -1 0;
#X obj 0 537 cnv 3 550 3 empty \$0-pddp.cnv.more_info more_info 8 12
0 13 -228856 -1 0;
#X text 98 514 (none);
#N canvas 107 323 428 268 Related_objects 0;
#X obj 1 1 cnv 15 425 20 empty \$0-pddp.cnv.subheading empty 3 12 0
14 -204280 -1 0;
#X text 8 2 [realtime] Related Objects;
#X obj 126 43 metro;
#X obj 23 43 cputime;
#X obj 81 43 timer;
#X text 20 134 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 19 183 The best places to find information about Pd's libraries
is:;
#X text 20 202 www.puredata.org and click on "Downloads" then "Software"
;
#X text 21 216 or;
#X text 20 231 iem.kug.ac.at/pdb/;
#X text 20 85 Related External Objects;
#X obj 20 110 pddp/helplink iemlib/t3_timer;
#X restore 102 597 pd Related_objects;
#X obj 78 385 cnv 17 3 35 empty \$0-pddp.cnv.let.0 0 5 9 0 16 -228856
-162280 0;
#X text 98 481 float;
#X obj 78 482 cnv 17 3 17 empty \$0-pddp.cnv.let.0 0 5 9 0 16 -228856
-162280 0;
#X obj 78 429 cnv 17 3 35 empty \$0-pddp.cnv.let.1 1 5 9 0 16 -228856
-162280 0;
#X obj 466 3 realtime;
#X obj 435 20 pddp/pddplink http://wiki.puredata.info/en/realtime -text
pdpedia: realtime;
#X msg 119 160 bang;
#X msg 94 138 bang;
#X floatatom 94 204 0 0 0 0 - - -;
#X text 166 206 Output is in milliseconds;
#X text 129 138 Click here to start or reset;
#X text 89 91 The [realtime] object measures elapsed "real" time as
measured by your operating system.;
#X obj 94 182 realtime;
#X text 157 161 Click here to get elapsed real time. Click again...and
again...to see periodic measurements from the start or reset time.
;
#X text 90 234 [realtime] works like essentially like a stop-watch.
Once it starts \, you can continue to "poll" [realtime] to view the
elapsed time.;
#X text 90 281 The odd aspect about comparing [realtime] to a stop-watch
is that a stop-watch can be stopped! [realtime] can only be started
or reset. It cannot be stopped.;
#N canvas 108 160 428 429 About_clocks 0;
#X text 20 60 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 text 21 145 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 22 205 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 21 369 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.;
#X obj 1 1 cnv 15 425 20 empty \$0-pddp.cnv.subheading empty 3 12 0
14 -204280 -1 0;
#X text 8 2 [realtime] About Clocks;
#X text 21 38 Why the discrepancies between clocks?;
#X restore 102 569 pd About_clocks;
#N canvas 105 140 428 400 Comparing_timers 0;
#X obj 1 1 cnv 15 425 20 empty \$0-pddp.cnv.subheading empty 3 12 0
14 -204280 -1 0;
#X text 8 2 [realtime] Comparing timers in Pd;
#X obj 45 296 time_measurements;
#X obj 45 192 bng 15 250 50 0 empty empty empty 0 -6 0 8 -262144 -1
-1;
#X floatatom 45 353 0 0 0 0 - - -;
#X floatatom 114 353 0 0 0 0 - - -;
#X floatatom 184 353 0 0 0 0 - - -;
#X text 20 108 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 20 371 Logical Time;
#X text 170 371 Real Time;
#X text 104 371 CPU Time;
#X obj 57 228 bng 15 250 50 0 empty empty empty 0 -6 0 8 -262144 -1
-1;
#X text 65 186 1 Measures elapsed time between two "bangs" from a [trigger]
object.;
#X text 77 220 2 Measures the amount of time Pd requires to turn on
DSP and start an oscillator.;
#X obj 97 260 bng 15 250 50 0 empty empty empty 0 -6 0 8 -262144 -1
-1;
#X text 118 252 3 Measures the amount of time Pd requires count to
three...please wait for approximately 3 seconds.;
#X text 20 39 As stated above \, [realtime] measures "real" or actual
time. This value may be slightly different that CPU time or "logical"
time. Pd offers two objects which measure CPU time and "logical" time.
See the reference documents for those objects for more information.
;
#X connect 2 0 4 0;
#X connect 2 1 5 0;
#X connect 2 2 6 0;
#X connect 3 0 2 0;
#X connect 11 0 2 1;
#X connect 14 0 2 2;
#X restore 102 547 pd Comparing_timers;
#X text 98 384 bang;
#X text 98 428 bang;
#X text 167 428 - a bang to the right inlet sends the elapsed time
to the outlet. Unlike most other objects in pd \, this is the "hot"
inlet \, i.e. \, it triggers the output.;
#X text 168 384 - a bang to the left inlet resets the timer. Unlike
most other objects in pd \, the left inlet of [realtime] is a "cold"
inlet \, i.e. \, it does not trigger the output.;
#X text 11 23 ask operating system for elapsed real time;
#X text 168 481 - elapsed time in milliseconds.;
#X obj 4 597 pddp/pddplink all_about_help_patches.pd -text Usage Guide;
#X connect 15 0 21 1;
#X connect 16 0 21 0;
#X connect 21 0 17 0;