Cancels a program state or definition‚ generally paired with a SET or DEFINE command. See also commands SET and DEFINE.
Arguments:
The arguments, which are names of variables, data sets, or other definitions can be specified using wildcards. The * wildcard matches any number of characters in the name; the ? wildcard matches exactly one character.
CANCEL ALIAS
Cancels a user-defined command alias.
yes? CANCEL ALIAS ALIAS_NAME
The command UNALIAS is an alias for CANCEL ALIAS.
CANCEL ATTRIBUTE
/OUTPUT /DATASET
Removes an attribute from a variable, or if /OUTPUT is specified, sets the output flag so that the attribute is not written to netCDF files when the variable is written. (See the section on commands for working with dataset and variable attributes)
yes? CANCEL ATTRIBUTE[/qualifiers] varname.attname
Examples:
This command removes the long_name attribute entirely from the variable sst.
yes? CANCEL ATTRIBUTE sst.long_name
These commands set a flag so that the AXIS attribute is not written for the coordinate variables COADSX, COADSY, and TIME are written to an netCDF file. This applies to the default dataset
yes? CANCEL ATTRIBUTE/OUTPUT (COADSX).AXIS yes? CANCEL ATTRIBUTE/OUTPUT (COADSY).AXIS yes? CANCEL ATTRIBUTE/OUTPUT (TIME).AXIS
Beginning with Ferret v6.85, CANCEL ATTRIBUTE may be applied to user-defined variables. For example here, we use SET ATTRIBUTE/LIKE= to inherit the attributes of a file variable to a user-defined variable. Then CANCEL ATT/OUTPUT so that the history attribute is not written for variable sst2.
yes? let sst2 = 2*sst yes? set att/like=sst sst2 yes? cancel att sst2.history yes? save/file=myfile.nc sst2
CANCEL AXIS
/MODULO /DEPTH /ALL /STRIDE
CANCEL AXIS forms the complement to DEFINE AXIS, or SET AXIS It is also applicable to "persistent" axes which are defined by netCDF files such as climatological_axes.cdf -- axes which are not associated with any variables in the netCDF file, itself, and are not automatically deleted when the data set is canceled.
yes? CANCEL AXIS AXIS_NAME
Attempts to CANCEL AXIS on a axis which is used by a variable in a currently open data set will be rejected with a message indicating the reason.
Command qualifiers for CANCEL AXIS:
Cancels the modulo nature of a user-defined axis.
yes? CANCEL AXIS/MODULO my_x_axis
or
yes? CANCEL AXIS/MODULO my_t*
Cancels the depth setting of a Z axis, which may have been set with a positive="down" attribute in a netCDF file, or for a user-defined axis with a DEFINE AXIS/DEPTH or SET AXIS/DEPTH command. If applied to an X, Y, or T axis, this qualifier is ignored.
yes? CANCEL AXIS/DEPTH my_z_axis
Cancels all axes that have been defined by the user, and restores any coordinate storage that was used to define irregular axes. It does not cancel axes defined when a data set is opened.
Cancels the strided behavior of an axis that was set to native striding by a SET AXIS/STRIDE command. See the discussion of netCDF strides.
/ALL /NOERROR /FMASK
Removes the specified data set from the list of available sets.
yes? CANCEL DATA_SET dset1, dset2, ..., dsetn
where each dset may be the name or number of a data set; or
yes? CANCEL DATA/ALL
See also SET DATA_SET, and SHOW DATA SET
Command qualifiers for CANCEL DATA_SET:
CANCEL DATA/ALL /NOERROR /FMASK
Eliminates all data sets from the list of accessible data sets.
Suppresses the error message otherwise generated when a data set that was never set is canceled. Useful in GO scripts for closing data sets that may or may not have been opened in previous usage of the script or elsewhere in the Ferret session.
Note that if a grid or axis from a netCDF file is used in the definition of a LET-defined variable (e.g. LET my_X = X[g=sst[D=coads_climatology]]) that variable definition will be invalidated when the data set is canceled (CANCEL DATA coads_climtology, in the preceding example). There is a single exception to this behavior: netCDF files such as climtological_axes.cdf, which define grids or axes that are not actually used by any variables. These grids and axes will remain defined even after the data set, itself, has been canceled. They may be deleted with explicit use of CANCEL GRID or CANCEL AXIS.
CANCEL DATA/FMASK
If a feature-mask was applied to a DSG dataset with SET DATA/FMASK, remove that setting.
The alias CLEARMASK is defined as CANCEL DATA/FMASK
CANCEL EXPRESSION
Un-specifies the current context expression. Ferret's "action" commands can be issued without an argument (e.g., yes? PLOT), in which case Ferret uses the current context expression. This expression is either the argument of the most recent action command, or an expression set explicitly with SET EXPRESSION.
yes? CANCEL EXPRESSION
The qualifier /ALL can be used with this command, but it exists for compatibility purposes only and has no effect.
CANCEL GRID
CANCEL GRID forms the complement to DEFINE GRID It is also applicable to "persistent" grids which are defined by netCDF files such as climatological_axes.cdf -- grids which are not associated with any variables in the netCDF file, itself, and are not automatically deleted when the data set is canceled.
Attempts to CANCEL GRID on a grid or axis which is used by a variable in a currently open data set will be rejected with a message indicating the reason.
/ALL /APPEND /FILE /FORMAT /HEADING /OUTTYPE /PRECISION
Toggles the effects of the SET LIST command. See command SET LIST.
yes? CANCEL LIST[/qualifiers]
Command qualifiers for: CANCEL LIST
Restores all aspects of the LIST command to their default behavior.
Resets the listed output to NOT append to existing file.
Resets the listed output to automatic file naming.
Resets the listed output to its default formatting.
Instructs listed output to omit the descriptive data header.
Restores default behavior for determining the data type when writing to NetCDF files.
Resets the precision of listed data to 4 significant digits.
/ALL /PERMANENT /TEMPORARY
Clears data currently cached in memory.
yes? CANCEL MEMORY[/qualifier]
Use this command to save memory space—by clearing data as soon as it is no longer needed virtual memory requirements can be reduced. This is especially useful for efficient batch processing. Default is CANCEL MEMORY/TEMPORARY.
Example:
To produce an animation using minimal virtual memory try:
yes? REPEAT/T=lo:hi:delta GO min_mem_movie
Where the file min_mem_movie.jnl contains
CONTOUR/FRAME temp[Z=0] ! contour plot CANCEL MEMORY/ALL ! clear memory for next time step
Command qualifiers for CANCEL MEMORY:
Clears all variables stored in memory.
Clears all "permanent" variables stored in memory (i.e., variables loaded into memory with LOAD/PERMANENT).
CANCEL MEMORY/TEMPORARY (default)
Clears all non-permanent variables stored in memory.
CANCEL MODE
Sets the state of a mode to "canceled".
yes? CANCEL MODE mode_name
(See command SET MODE for descriptions of modes.)
This command is unnecessary in Ferret version 3.1 and later; it is provided for compatibility with older versions of Ferret. It restores the default movie file name (ferret.mgm) but is not needed to conclude capturing graphics to a movie file.
yes? CANCEL MOVIE
The qualifier /ALL can be used with this command, but it exists for compatibility purposes only and has no effect.
Cancels settings made with SET NCCACHE.
yes? CANCEL NCCACHE
CANCEL PYVAR
Pyferret only
CANCEL PYVAR /ALL /DATASET
PyFerret has the ability, using methods in the pyferret Python module, to add data from Python as Ferret data variables. The CANCEL PYVAR command enables one to remove these added variables from Ferret.
CANCEL REDIRECT
Stops redirecting messages and data listings to a file. Any information queued for writing to the file is completed and the file is closed.
- The additional arguments STDOUT and/or STDERR can be given to indicate which information is no longer redirected. If STDOUT is given, informational messages and data listings will no longer be redirected. If STDERR is given, error and warning messages will no longer be redirected. If neither is given, all redirections are closed.
- The STDOUT and STDERR redirects can be canceled at different times even if they were created with one SET REDIRECT command..
- Information written to a file may not be visible until that file is closed by Ferret.
See set redirect for more information on redirecting messages and data listings.
CANCEL REGION
/I/J/K/L/M/N /X/Y/Z/T/E/F /ALL
Cancels part or all of the current or named region.
yes? CANCEL REGION[/qualifier] [region_name]
Examples:
yes? CANCEL REGION !clear the current region yes? CANCEL REGION/T !eliminate T from the current context yes? CANCEL REGION reg1 !clear the region named "reg1"
Command qualifiers for CANCEL REGION:
CANCEL REGION/I /J /K /L/M/N /X /Y /Z /T/E/F
Eliminates I, J, K, L, M, N, X, Y, Z, T, E or F axis information from current context or named region.
Eliminates ALL stored region information (rarely used).
CANCEL SYMBOL
/ALL
Deletes a user-defined symbol (string variable) definition.
yes? CANCEL STRING[/qualifier] [symbol_name]
Command qualifiers for CANCEL SYMBOL:
Deletes all user-defined symbol definitions.
Examples:
yes? CANCEL SYMBOL my_x_label !eliminate my_x_label from the definitions yes? CANCEL SYMBOL *x_label !remove all strings ending in x_label yes? CANCEL SYMBOL/ALL !remove all user-defined symbols.
CANCEL TEXT
PyFerret Only
/ALL /FONT /COLOR /ITALIC /BOLD /ISIZ [text-groupname][, text-groupname, ...]
Restore the default settings for PyFerret text and fonts. CANCEL TEXT with no arguments or qualifiers restores all text groupings to the defaults. The argument is a text group or list of groups. The requested text settings for those groups are restored to their defaults. See also: SET TEXT and SHOW TEXT.
/ALL
Restore all text characteristics to their defaults. If no qualifiers are given, all characteristics are restored to default values.
/FONT
Restore the font to the default (currently the Hershey font).
/COLOR
Restore the text color to black.
/ITALIC
Remove the Italic setting.
/BOLD
Remove the Bold setting.
/ISIZ
Return to the default text sizes.
/ALL /DATASET
Deletes a user-defined variable definition.
yes? CANCEL VARIABLE[/qualifier] [var_name]
Command qualifiers for CANCEL VARIABLE:
CANCEL VARIABLE/ALL /DATASET /NOERROR
Deletes all user-defined variable definitions.
Examples:
yes? CANCEL VARIABLE my_sst !eliminate my_sst from the definitions yes? CANCEL VARIABLE *wind !delete all variables ending in wind yes? CANCEL VARIABLE tau? !delete variables named tau plus one character yes? CANCEL VARIABLE/ALL !delete all user-defined defined variables
Deletes user define variables associated with the named dataset, which were defined by a DEFINE VARIABLE/DATASET command.
Suppresses the error message otherwise generated when a variable that was never defined is canceled. Useful in GO scripts for canceling variables that have been opened in previous usage of the script or elsewhere in the Ferret session. This has an effect only on named lists of variables, e.g. the foloowing command will cancel a and/or b, if they are defined.
yes? CANCEL VARIABLE/NOERROR a,b
Note that CANCEL VARIABLE name*, where the variables to be canceled are given as a template with * in the name, always ignores any naming that doesn't match, even if /NOERROR is not given.
CANCEL VIEWPORT
Cancels a defined viewport or cancels use of viewports.
yes? CANCEL VIEWPORT view_name !un-define view_name yes? CANCEL VIEWPORT !return to full window output
CANCEL WINDOW
/ALL
Removes graphics window(s) from the screen.
yes? CANCEL WINDOW n !or yes? CANCEL WINDOW/ALL
Command qualifiers for CANCEL WINDOW:
Removes all graphics windows.