MGH_TF_LINEAR Name
MGH_TF_LINEAR Purpose
This function is designed for use with the TICKFORMAT and
TICKFRMTDATA properties of IDLgrAxis. Given a real value, it
applies a linear transformation & returns a string representing
the result. Calling Sequence
Result = MGH_TF_LINEAR(Direction, Index, Value)
Positional Parameters
Direction
Axis direction, required by the TICKFORMAT interface but ignored.
Index
Axis index, required by the TICKFORMAT interface but ignored.
Value
The real value to be formatted.
Level
Level is the index of the axis level for the current tick value
to be labeled. (Level indices start at 0.) This parameter takes
its value from the dimension of TICKUNITS.
Keyword Parameters
DATA
Specify this keyword to control the linear transformation and
format. The keyword value should be a structure with one or more
of the tags "offset", "scale", "format" and "round". The default
is equivalent to {offset: 0., scale: 1., format: '', round: 0}.
Return Value
The function returns a scalar string representing:
output = data.offset + data.scale * input
If data.round is set to a 'true' value then this is rounded. The
format is controlled by data.format. If this is not supplied a
default format is generated by MGH_FORMAT_FLOAT.
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This software is provided subject to the following conditions:
1. NIWA makes no representations or warranties regarding the
accuracy of the software, the use to which the software may
be put or the results to be obtained from the use of the
software. Accordingly NIWA accepts no liability for any loss
or damage (whether direct of indirect) incurred by any person
through the use of or reliance on the software.
2. NIWA is to be acknowledged as the original author of the
software where the software is used or presented in any form.
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Modification History
Mark Hadfield, 1999-05:
Written.
Mark Hadfield, 2001-03:
Merged changes by George Constantinides to take advantage of
multi level axis of IDL 5.4
Mark Hadfield, 2001-05:
Added rounding via the "round" tag in DATA. I might generalise
this some day.
Mark Hadfield, 2003-01:
Now accepts a "floor" tag in DATA.