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Created page with "== Notes on time consumption == See comments from edward. <br> [http://article.gmane.org/gmane.science.nmr.relax.user/1468 mail correspondance] == Example == A performed 'cpm..."
== Notes on time consumption ==
See comments from edward. <br>
[http://article.gmane.org/gmane.science.nmr.relax.user/1468 mail correspondance]
== Example ==
A performed 'cpmg fixed' relaxation dispersion analysis, for a dataset with 68 residues. <br>
Analysed with 22 intensity files, with 4 triple replications. <br>
Time consumption was approximately 20 hours. <br>
The analysed models were: R2eff', 'No Rex','LM63','CR72'
== What takes time ? ==
=== Precision ===
By default relax uses much higher precision optimisation than most other softwares. <br>
This is based on the philosophy that more accurate results are worth the wait, <br>
especially considering that this time is relatively small in comparison to the measurement and processing time
(and adding the inevitable re-measurements). <
=== Monte Carlo simulation for accurately determining parameter errors ===
Lots of Monte Carlo simulations (500 is standard) are used for really accurately determining parameter errors. <br>
For comparison, note that a full a Lipari and Szabo model-free analysis can take between 1 day and 2 weeks to complete.
== How to speed up initial phase ==
For initial analyses where errors are not so important, the number of simulations can be dropped massively to speed things up. <br>
If errors are not important for specific cases, set the number of MC sims to 3, and the analysis will perform much more rapidly.
The result is that the error estimates of the parameters are horrible but, but in some cases, excluding publication, that is not such a problem. <br>
This will not affect model selection either.
[[Category:Time_of_running]]
See comments from edward. <br>
[http://article.gmane.org/gmane.science.nmr.relax.user/1468 mail correspondance]
== Example ==
A performed 'cpmg fixed' relaxation dispersion analysis, for a dataset with 68 residues. <br>
Analysed with 22 intensity files, with 4 triple replications. <br>
Time consumption was approximately 20 hours. <br>
The analysed models were: R2eff', 'No Rex','LM63','CR72'
== What takes time ? ==
=== Precision ===
By default relax uses much higher precision optimisation than most other softwares. <br>
This is based on the philosophy that more accurate results are worth the wait, <br>
especially considering that this time is relatively small in comparison to the measurement and processing time
(and adding the inevitable re-measurements). <
=== Monte Carlo simulation for accurately determining parameter errors ===
Lots of Monte Carlo simulations (500 is standard) are used for really accurately determining parameter errors. <br>
For comparison, note that a full a Lipari and Szabo model-free analysis can take between 1 day and 2 weeks to complete.
== How to speed up initial phase ==
For initial analyses where errors are not so important, the number of simulations can be dropped massively to speed things up. <br>
If errors are not important for specific cases, set the number of MC sims to 3, and the analysis will perform much more rapidly.
The result is that the error estimates of the parameters are horrible but, but in some cases, excluding publication, that is not such a problem. <br>
This will not affect model selection either.
[[Category:Time_of_running]]
