[postgis-devel] [PostGIS] #703: measures test failure

[PostGIS]

#703: measures test failure
---------------------+------------------------------------------------------
 Reporter:  strk     |       Owner:  pramsey      
     Type:  defect   |      Status:  new          
 Priority:  medium   |   Milestone:  PostGIS 2.0.0
Component:  postgis  |     Version:  trunk        
 Keywords:           |  
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Comment(by nicklas):

 An even more distilled version is to just compile:

 {{{

 #include <stdio.h>

 main()
 {
 double r=1100.0/1375.0;
 double px = -40.0+r*(50.0);
 printf("r=%.16e\npx=%.16e\n",r, px);
 }
 }}}


 gives me on ubuntu 64 bit (and probably win 32 bit):[[BR]]
 r=8.0000000000000004e-01[[BR]]
 px=2.2204460492503131e-15[[BR]]
 [[BR]]
 and on ubuntu 32 bit:[[BR]]
 r=8.0000000000000004e-01[[BR]]
 px=0.0000000000000000e+00[[BR]]
 [[BR]]

 Regina, I don't think they are related because this issue, I have known
 some time but have not had time to look at and thought it is just one of
 those precision errors, and you say it didn't crash last friday.


 /Nicklas

-- 
Ticket URL: <http://trac.osgeo.org/postgis/ticket/703#comment:10>
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