IOBasic

Gabrielle Allen
Thomas Radke

Date

Abstract

Thorn IOBasic provides I/O methods for outputting scalar values in ASCII format into files and for printing them as runtime information to screen.

1 Purpose

Thorn IOBasic registers 2 I/O methods with the I/O interface in the flesh which both output the same following information:

The I/O methods differ in the destination the output is written to:

2 IOBasic Parameters

Parameters to control the Scalar I/O method are:

Parameters to control the Info I/O method are:

All of the above parameters marked as steerable can be changed at runtime.

3 Examples

3.1 Example for Info Output

The following parameter settings request info output for variables grid::r, wavetoy::phi (both are CCTK grid functions) and mythorn::complex (a complex CCTK scalar) at every other iteration.

The minimum and maximum of grid::r is printed according to the list of default reductions for info output (parameter IOBasic::outInfo_reductions). This list is overridden for wavetoy::phi where only the L2 norm is output as specified in the option string for this variable. You can also add other reduction operators within the {} braces.

For the scalar variable mythorn::complex both the real and imaginary part are printed.

  IOBasic::outInfo_every      = 2  
  IOBasic::outInfo_vars       = "grid::r  
                                 wavetoy::phi{reductions = ’norm2’}  
                                 mythorn::complex"  
  IOBasic::outInfo_reductions = "minimum maximum"

The resulting screen output would look like this:

---------------------------------------------------------------------------------------------  
  it  |          | GRID::r                     | WAVETOY::phi | MYTHORN::complex            |  
      |    t     | minimum      | maximum      | norm2        | real part    | imag part    |  
---------------------------------------------------------------------------------------------  
    0 |    0.000 |   0.02986294 |   0.86602540 |   0.04217014 |   6.90359593 |   0.00000000 |  
    2 |    0.034 |   0.02986294 |   0.86602540 |   0.00934749 |   6.90359593 |   0.00000000 |  
    4 |    0.069 |   0.02986294 |   0.86602540 |   0.02989811 |   6.90359593 |   0.00000000 |  
    6 |    0.103 |   0.02986294 |   0.86602540 |   0.05899959 |   6.90359593 |   0.00000000 |  
    8 |    0.138 |   0.02986294 |   0.86602540 |   0.07351147 |   6.90359593 |   0.00000000 |  
   10 |    0.172 |   0.02986294 |   0.86602540 |   0.07781795 |   6.90359593 |   0.00000000 |

3.2 Example for Scalar Output

The following parameter settings request scalar output for all grid function variables in the group grid::coordinates and for the scalar variable grid::coarse_dx.
Output occurs every 10th iteration. gnuplot output style is selected for the ASCII files which are placed into a subdirectory scalar_output. The minimum and maximum of grid::r is printed according to the list of default reductions for scalar output (parameter IOBasic::outScalar_reductions). This list is overridden for wavetoy::phi where only the L1 norm is output as specified in the option string for this variable. You can also add other reduction operators within the {} braces.

  IOBasic::outScalar_every      = 10  
  IOBasic::outScalar_vars       = "grid::coordinates grid::coarse_dx wavetoy::phi{reductions = ’norm1’}"  
  IOBasic::outScalar_reductions = "minimum maximum"  
  IOBasic::outScalar_style      = "gnuplot"  
  IOBasic::out_dir              = "scalar_output"

This would create the following ASCII files:

  ~/Cactus/par> ls scalar_output  
  coarse_dx.asc  r_minimum.asc  x_minimum.asc  y_minimum.asc  z_minimum.asc  
  r_maximum.asc  x_maximum.asc  y_maximum.asc  z_maximum.asc  phi_norm1.asc

4 Comments

Possible Reduction Operations
In order to get output of reduction values for CCTK_GF and CCTK_ARRAY variables you need to activate a thorn which provides reduction operators (eg. thorn PUGHReduce in the CactusPUGH arrangement). For a list of possible reduction operations please refer to the documention of this reduction thorn.
Getting Output from IOBasic’s I/O Mehtods
You obtain output by an I/O method by either

For a description of basic I/O parameters and the I/O function interface to invoke I/O methods by application thorns please see the documentation of thorn IOUtil and the flesh.
Building Cactus configurations with IOBasic
Since IOBasic uses parameters from IOUtil it also needs this I/O helper thorn be compiled into Cactus and activated at runtime in the ActiveThorns parameter in your parameter file.

5 Parameters




out_dir
Scope: private  STRING



Description: Output directory for IOBasic’s scalar files, overrides IO::out_dir



Range   Default: (none)
.+
A valid directory name
An empty string to choose the default from IO::out_dir






out_format
Scope: private  STRING



Description: Which format for Scalar floating-point number output



Range   Default: .13f
see [1] below
output with given precision in exponential / floating point notation



[1]

\^({\textbackslash}.[1]?[0-9])?[EGefg]\$




outinfo_criterion
Scope: private  KEYWORD



Description: Criterion to select Info output intervals



Range   Default: iteration
never
Never output
iteration
Output every so many iterations
time
Output every that much coordinate time






outinfo_dt
Scope: private  REAL



Description: How often to do Info output



Range   Default: -2
(0:*
In intervals of that much coordinate time
As often as possible
-1
Disable output
-2
Default to IO::out_dt






outinfo_every
Scope: private  INT



Description: How often to do Info output



Range   Default: -1
1:*
Every so many iterations
0:
Disable Info output
-1:
Default to IO::out_every






outinfo_reductions
Scope: private  STRING



Description: List of reductions to output as Info to screen



Range   Default: minimum maximum
.+
Space-separated list of reduction operators






outinfo_vars
Scope: private  STRING



Description: Variables to output as Info to screen



Range   Default: (none)
.+
Space-separated list of fully qualified variable/group names
An empty string to output nothing






outscalar_criterion
Scope: private  KEYWORD



Description: Criterion to select Scalar output intervals



Range   Default: iteration
never
Never output
iteration
Output every so many iterations
time
Output every that much coordinate time






outscalar_dt
Scope: private  REAL



Description: How often to do Scalar output



Range   Default: -2
(0:*
In intervals of that much coordinate time
As often as possible
-1
Disable output
-2
Default to IO::out_dt






outscalar_every
Scope: private  INT



Description: How often to do Scalar output



Range   Default: -1
1:*
Every so many iterations
0:
Disable Scalar output
-1:
Default to IO::out_every






outscalar_reductions
Scope: private  STRING



Description: List of reductions to output into files



Range   Default: minimum maximum norm1 norm2
.+
Space-separated list of reduction operators






outscalar_style
Scope: private  KEYWORD



Description: Which style for Scalar output



Range   Default: xgraph
gnuplot
1D output readable by gnuplot
xgraph
1D output readable by xgraph






outscalar_vars
Scope: private  STRING



Description: Variables to output into files



Range   Default: (none)
.+
Space-separated list of fully qualified variable/group names
An empty string to output nothing






io_out_dir
Scope: shared from IO STRING






new_filename_scheme
Scope: shared from IO BOOLEAN






out_criterion
Scope: shared from IO KEYWORD






out_dt
Scope: shared from IO REAL






out_every
Scope: shared from IO INT






out_fileinfo
Scope: shared from IO KEYWORD






strict_io_parameter_check
Scope: shared from IO BOOLEAN






verbose
Scope: shared from IO KEYWORD



6 Interfaces

General

Implements:

iobasic

Inherits:

io

Grid Variables

6.0.1 PRIVATE GROUPS




  Group Names     Variable Names     Details   




next_info_output_time   compact0
next_info_output_time   dimensions0
  distributionCONSTANT
  group typeSCALAR
  timelevels1
 variable typeREAL




next_scalar_output_time   compact0
next_scalar_output_time  dimensions0
  distributionCONSTANT
  group typeSCALAR
  timelevels1
 variable typeREAL




7 Schedule

This section lists all the variables which are assigned storage by thorn CactusBase/IOBasic. Storage can either last for the duration of the run (Always means that if this thorn is activated storage will be assigned, Conditional means that if this thorn is activated storage will be assigned for the duration of the run if some condition is met), or can be turned on for the duration of a schedule function.

Storage

 

Always:  
next_info_output_time next_scalar_output_time 
   

Scheduled Functions

CCTK_STARTUP

  iobasic_startup

  startup routine

 

 After: ioutil_startup
 Language:c
 Type: function

CCTK_INITIAL

  iobasic_init

  initialisation routine

 

 Language:c
 Type: function